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W140 Fix it Yourself Articles

468K views 267 replies 83 participants last post by  daone3256 
#1 · (Edited by Moderator)
Do you think we could have a database type thing so newbies can get acess to the things we all have to know about..we can get one for all those words and pics about silly things like bulbs and asr lights and window regs and...........we are repeating stuff constantly..And whilst I dont mind that.. would be nice to let others help themseves.. dont you think??????
RSVP
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MOVED THE MAINTENANCE THREAD INTO THIS ONE .
http://www.benzworld.org/forums/w140-s-class/1636494-maintenance-manuals.html
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MANUALS + LITERATURE + DIY SOURCES
Articles -thanks to Robert144
MBUSA old website -thanks to Thom_7
Buyer's Guide -by Merc-S600
Owners Manual PDF -thanks to Bayhas
Parts Manufacturer Country of Origin -thanks to Mercedes Mechanic
Zubehor-Accessories-Options Catalog
v12 uber alles cached link
VIN Decode Help -by MafiaDON
VIN Decoder
W140.de Photo Gallery
Maintenance Tips and DIYs -by Greg
Brabus W140 Catalog -by SL Brabus

HEATING & COOLING
AC Blower Regulator replacement -by MOS500 06/30/09
Cool Harness - Aux Fan Upgrade
DIY Coolant Service -by G-AMG
AC Vent Issue
AC Vent Issue 2 -by dr.charlesatlas
Replacing Evaporator and Removing the Dash -by Adrian126

ENGINE, TRANSMISSION & DRIVELINE
Where is the power steering reservoir?
Rear Engine Transmission Mount -by G-AMG
How to tell how worn out your 722.6 Transmission is -by MAVA
Fuel Filter -by Rainmaker
Complete Fuel System Cleaning -by G-AMG
Conductor Plate and Pressure Regulator Spring -by G-AMG
Steering Pump -by G-AMG
Rear Diff Oil Change -by G-AMG
Transmission Oil
Shifter Linkage Bushing -by G-AMG
Oxygen O² sensor - all 4 -by G-AMG

ELECTRICAL & WIRING
Antenna - see AUDIO below
Stereo - see AUDIO below
DIY Wiring Loom -by ScrapingScrap
DIY Rewiring ETA -from v12uberalles.com
Lumbar Bladder Replacement -by G-AMG
3rd brake lamp bulb replacement -by Stox & MOS500
3rd Brake Lamp LED Upgrade -by z168
Battery Service -by G-AMG
Center Lock Pump
Fuse Charts -by Bayhas
Dissecting the PSE pump -by MOS500
Side Mirror Repair -by MOS500
Warning Buzzer -not W140 specific and incomplete DIY, lifted from mercedesshop
1995 S600 Wiring Diagram -by Mercedes Mechanic
Gauge Cluster Bulb Replacement -by G-AMG

BRAKES, SUSPENSION & STEERING
Spring & Rear Bushing Replacement -by MOS500
Rear Spring Removal -by G-AMG
Power Steering Pump Overhaul -by G-AMG 11/10/09
DIY Brake Pedal groan/squeal -by MikeJT
Airbag & Steering Wheel Removal -by G-AMG
ASR Fixed! -by drcane
SLS Delete -by snik
DIY Rear Shock and SLS Delete -by MafiaDON

TROUBLESHOOTING & DIAGNOSTICS
Opening Trunk when Battery is Dead
Opening Trunk when Battery is Dead 2
P0455 Code -by Brett SanDiego
Hood Bonnet Not Opening

EXTERIOR & LIGHTING
Euro Fender Lamps / Side Markers -by z168
Headlight Removal -by G-AMG
Headlight Wipers
Headlights: US vs Euro
Modding How-to -by Hetzle
Wheel & Tire Fitment Thread
Trailer Hitch Install
Side Mirror Gasket Repair -by MAVA


AUDIO
Antenna Rebuild DIY -by innovation560
Antenna Rebuild DIY II -by nhzruthless818
Antenna Rebuild DIY III -lifted from K6JRF.com
DIY Aux Input -lifted from mercedesshop
DIY Aux Input 2 -lifted from mercedesshop
Becker Aux Input -by z168
Becker Aux Input 2 -by bobs
Becker Aux Input - late model
iPod/Aux Integration with Stock Becker Stereo -by LWB250
Integrating Aftermarket Stereo to BOSE Amp (for preface models 91-93) -by Merc-S600
Some Stereo Help
Generic DIY bluetooth integration (1) (2) - not MB content

INTERIOR
Center Console & Shifter Wood Removal - thanks to Rainmaker for the info
Cluster Removal -by bobs
Coolbox Fridge Option & Fuel Tank Info -by berlin420
Door Strap Replacement -by G-AMG
Euro Fire Extinguisher -by z168
Euro Trunk Warning Triangle -by z168
Interior Wood Trim Reference -by dbs600 & syljua
Rear 2-seat Conversion
Airbag differences (Early v Late model)

THOUGHTS ON W140 OWNERSHIP
Reality Check -by nimrodthewombat
Thoughts on ownership - W140 v LS400 -by SaleenS7
Enthusiast Perspective -by Stryker-1999 S600
More
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#9 ·
Knowlege base

We each have our own skills and experiences tricks and tweaks of this Unique piece of mechanical and electrical Machinery, and most of the time in conversations I find I know more about the car than the service personel at my local stealers.
It is possibly true, with your own cars as well as others cars..we need to be able to help ourselves..Rather than rely on those whos only interest is £or$ pre hour or unit....


"Knowledge is worthless unless shared"....tjn
 
#10 ·
RE: Knowlege base

I'm in the process of creating a web page that describes some of the projects I've undertaken. Unfortunately, I did not take pics for most of my projects as I did not have a digital camera at the time. Maybe I can just do a narrative in those cases. I'm now writing up my Throttle Actuator rewire saga. I'll let you know what the address of the web page will be once I set it up. Once we figure out how to set up our knowledge base, I'd be happy to contribute what I have to it as well.
 
#17 ·
RE: Knowlege base

i think this is a great idea. and just so you experienced folks know, i, for one, greatly appreciate it when you take the time to 'nurture along' a relative novice like myself. maybe one day i can reciprocate. your patience is impressive and, hopefully, contagious. Sebastian and i thank you once again! [8D]
 
#19 ·
AC tests

Yeh there is a self diagnostics sequence that you can do ignition on , turn the wheels to white, press both auto buttons for 20+secs then press REST for 10 secs, NO1 appears left window in car temp rh window
these are the tests

Description and Operation
The automatic air conditioner (A/C) in the W140 models can be diagnosed by performing the following steps. There are two (2) basic tests; the first reads the actual sensor values; the second, readout of the DTCs.

The display windows (arrows) show in sequence the actual temperature sensor readings, refrigerant pressure, blower control voltage, software status and control module version.

Reading Sensor Values
The following preparation are required for test:
Air Conditioner control setup - Set the TEMPERATURE selector wheels into the WHITE [white] area.
- Turn Ignition to ON or preferably, start car and let it idle
- Press left and right [AUTO] buttons
- Within 20 seconds, then press [REST] button until the display changes (about 9 secs)
- Number '1' appears in the left window; the in-car temperature in the right - OR -
HI if there is a short circuit, LO is there is an open circuit.
- By pressing the left [AUTO] button, the next value is displayed in the right window per the table below.
- Press the right [AUTO] button, to go back to the previous value displayed.
- Press [REST] button to end the test program.

Test Step Sensor Value Display 1 In-car temperature sensor w/ aspirator blower (B10/4) 2 Outside temperature sensor (B10/5) 3 Left heater core temperature sensor (B10/2)* 4 Right heater core temperature sensor (B10/3)* 5 Evaporator temperature sensor (B10/6) 6 Coolant temperature sensor (B10/8)*
7 Refrigerant pressure in bar (06 = 6 bar) 8 Blower control voltage from B(min) - 60(max) 9 Software status, A/C push button control module, manufacturer Bosch: 57, 58, etc.: manufacturer Kammer: 02, 03, etc. 10 ** Left heater core temperature sensor (B10/9) (rear climate control) 11 ** Right heater core temperature sensor (B10/10) (rear climate control) 12 ** Evaporator temperature sensor (B10/11) (rear climate control) 13 ** Software status, rear A/C control unit, manufacturer Bosch: 42 *** 16 Active charcoal filter: R = equipped; O = not equipped


Reading DTCs from Auto A/C System
The following preparation are required for test:
- Set the LEFT TEMPERATURE selector wheel into the RED [red] area.
- Set the RIGHT TEMPERATURE selector wheel into the BLUE [blue] area.
- Turn Ignition to ON.
- Press left [AUTO] button.
- Within 10 seconds, simultaneously press [REST] and [O] buttons until the displays shows permanent stored DTCs in memory per the table below. Press the RIGHT [AUTO] button until all stored DTCs are displayed. Record each as they are displayed.
- Each fault has a specific DTC. The letter 'E' (error) along with the hundredth digit of the display code will show in the window. The tenth and single digit of the code displays in the right window. By pressing the right [AUTO], the next DTC stored in memory will be displayed.
- Turn the ignition OFF and repair recorded DTCs according to the respective diagnostic chart.

- To delete stored DTCs, repeat the first five (5) steps, then press the LEFT [AUTO] for the letter 'D' (delete) to appear in the window. By pressing the right [AUTO] the display code will be deleted from memory. Continue to press the left and right [AUTO] buttons until all codes are deleted from memory. The display will show 'E0 00'.
- Return the temperature selector to normal setting.

Display Code Possible Cause
E0 01 No faults in system
E0 02 A/C push button control module (N22)
E0 03 Rear climate control module
E0 06 Connection to switchover valve block (Y11)
E0 07 Data exchange (CAN B), short circuit
E0 08 Data exchange (CAN A), short circuit
E0 09 Data exchange (CAN A and B), short circuit
E0 10 Repeat displaying for malfunction readout
E0 11 Data exchange (CAN B), open circuit
E0 12 Data exchange (CAN A), open circuit
E0 13 connection to rear climate control module
E0 14 Data exchange (CAN B), open circuit (rear climate control)
E0 15 Data exchange (CAN A), open circuit (rear climate control)
E0 16 In-car temperature sensor w/ aspirator blower (B10/4), short circuit *)
E0 17 In-car temperature sensor w/ aspirator blower (B10/4), short circuit **)
E0 18 In-car temperature sensor w/ aspirator blower (B10/4), open circuit *)
E0 19 In-car temperature sensor w/ aspirator blower (B10/4), open circuit **)
E0 24 Left heater core temperature sensor (B10/2), short circuit *)
E0 25 Left heater core temperature sensor (B10/2), short circuit **)
E0 26 Left heater core temperature sensor (B10/2), open or short circuit *)
E0 27 Left heater core temperature sensor (B10/2), open or short circuit **)
E0 28 Right heater core temperature sensor (B10/3), short circuit *)
E0 29 Right heater core temperature sensor (B10/3), short circuit **)
E0 30 Right heater core temperature sensor (B10/3), open or short circuit *)
E0 31 Right heater core temperature sensor (B10/3), open or short circuit **)
E0 32 Outside temperature sensor (B10/5), short circuit *)
E0 33 Outside temperature sensor (B10/5), short circuit **)
E0 34 Outside temperature sensor (B10/5), open or short circuit *)
E0 35 Outside temperature sensor (B10/5), open or short circuit **)
E0 36 Evaporator temperature sensor (B10/6), short circuit *)
E0 37 Evaporator temperature sensor (B10/6), short circuit **)
E0 38 Evaporator temperature sensor (B10/6), open or short circuit *)
E0 39 Evaporator temperature sensor (B10/6), open or short circuit **)
E0 40 A/C Coolant temperature sensor (B10/8), short circuit *)
E0 41 A/C system coolant temperature sensor (B10/8), short circuit **)
E0 42 A/C system coolant temperature sensor (B10/8), open or short circuit *)
E0 43 A/C system coolant temperature sensor (B10/8), open or short circuit **)
E0 44 Refrigerant pressure sensor (B12), short circuit *)
E0 45 Refrigerant pressure sensor (B12), short circuit **)
E0 46 Refrigerant pressure sensor (B12), open or short circuit *)
E0 47 Refrigerant pressure sensor (B12), open or short circuit **)
E0 48 Left temperature selector wheel, short circuit *)
E0 49 Left temperature selector wheel, short circuit **)
E0 50 Left temperature selector wheel, open or short circuit *)
E0 51 Left temperature selector wheel, open or short circuit **)
E0 52 Right temperature selector wheel, short circuit *)
E0 53 Right temperature selector wheel, short circuit **)
E0 54 Right temperature selector wheel, open or short circuit *)
E0 55 Right temperature selector wheel, open or short circuit **)
E0 72 Heater supply unit circulation pup (A31m1), short circuit *)
E0 73 Heater supply unit circulation pup (A31m1), short circuit **)
E0 74 Heater supply unit circulation pup (A31m1), open or short circuit *)
E0 75 Heater supply unit circulation pup (A31m1), open or short circuit **)
E0 76 Heater supply unit circulation pump (A31m1), over load *)
E0 77 Heater supply unit circulation pup (A31m1), over load **)
E0 80 Heater supply unit left duovalve (A31y1), short circuit *)
E0 81 Heater supply unit left duovalve (A31y1), short circuit **)
E0 82 Heater supply unit left duovalve (A31y1), open or short circuit *)
E0 83 Heater supply unit left duovalve (A31y1), open or short circuit **)
E0 84 Heater supply unit right duovalve (A31y2), short circuit *)
E0 85 Heater supply unit right duovalve (A31y2), short circuit **)
E0 86 Heater supply unit right duovalve (A31y2), open or short circuit *)
E0 87 Heater supply unit right duovalve (A31y2), open or short circuit **)
E0 88 A/C compressor ground activation *)
E0 89 A/C compressor ground activation **)
E0 90 A/C compressor ground activation, open or short circuit *)
E0 91 A/C compressor ground activation, open or short circuit **)
E0 96 Auxiliary fan, 1st activation, short circuit *)
E0 97 Auxiliary fan, 1st activation, short circuit **)
E0 98 Auxiliary fan, 1st activation, open or short circuit *)
E0 99 Auxiliary fan, 1st activation, open or short circuit **)
E1 00 Auxiliary fan, 2nd stage activation, short circuit *)
E1 01 Auxiliary fan, 2nd stage activation, short circuit **)
E1 02 Auxiliary fan, 2nd stage activation, open or short circuit *)
E1 03 Auxiliary fan, 2nd stage activation, open or short circuit **)
E1 04 Auxiliary fan, 3nd stage activation, short circuit *)
E1 05 Auxiliary fan, 3nd stage activation, short circuit **)
E1 06 Auxiliary fan, 3nd stage activation, open or short circuit *)
E1 07 Auxiliary fan, 3nd stage activation, open or short circuit **)
E1 08 After-run pump relay (K30), power supply, short circuit *) ***)
E1 09 After-run pump relay (K30), power supply, short circuit **) ***)
E1 10 After-run pump relay (K30), power supply, open or short circuit *) ***)
E1 11 After-run pump relay (K30), power supply, open or short circuit **) ***)
E1 12 Engine rpm increase diode matrix (V2), short circuit *)
E1 13 Engine rpm increase diode matrix (V2), short circuit **)
E1 14 Engine rpm increase diode matrix (V2), open or short circuit *)
E1 15 Engine rpm increase diode matrix (V2), open or short circuit **)
E1 16 Charcoal filter actuator (A32m2) (OPEN), short circuit *)
E1 17 Charcoal filter actuator (A32m2) (OPEN), short circuit **)
E1 18 Charcoal filter actuator (A32m2) (OPEN), open or short circuit *)
E1 19 Charcoal filter actuator (A32m2) (OPEN), open or short circuit **)
E1 20 Charcoal filter actuator (A32m2) (CLOSED), short circuit *)
E1 21 Charcoal filter actuator (A32m2) (CLOSED), short circuit **)
E1 22 Charcoal filter actuator (A32m2) (CLOSED), open or short circuit *)
E1 23 Charcoal filter actuator (A32m2) (CLOSED), open or short circuit **)
E1 28 Left rear heater core temperature sensor (B10/9), short circuit *)
E1 29 Left rear heater core temperature sensor (B10/9), short circiut **)
E1 30 Left rear heater core temperature sensor (B10/9), short or open *)
E1 31 Left rear heater core temperature sensor (B10/9), short or open **)
E1 32 Right rear heater core temperature sensor (B10/10), short *)
E1 33 Right rear heater core temperature sensor (B10/10), short **)
E1 34 Right rear heater core temperature sensor (B10/10), short or open *)
E1 35 Right rear heater core temperature sensor (B10/10), short or open **)
E1 36 Left temperature selector wheel, short *)
E1 37 Left temperature selector wheel, short **)
E1 38 Left temperature selector wheel, short *)
E1 39 Left temperature selector wheel, short or open **)
E1 40 Right temperature selector wheel, short *)
E1 41 Right temperature selector wheel, short **)
E1 42 Right temperature selector wheel, short or open *)
E1 43 Right temperature selector wheel, short or open **)
E1 44 Right evaporator temperature selector wheel (B10/11), short *)
E1 45 Right evaporator temperature selector wheel (B10/11), short **)
E1 46 Right evaporator temperature selector wheel (B10/11), short or open *)
E1 47 Right evaporator temperature selector wheel (B10/11), short or open **)
E1 48 Coolant circulation pump (A31/1m1), short *)
E1 49 Coolant circulation pump (A31/1m1), short **)
E1 50 Coolant circulation pump (A31/1m1), short or open *)
E1 51 Coolant circulation pump (A31/1m1), short or open **)
E1 52 Coolant circulation pump (A31/1m1), overload *)
E1 53 Coolant circulation pump (A31/1m1), overload **)
E1 56 Left duovalve (water value, A31/1y1, short *)
E1 57 Left duovalve (water value, A31/1y1, short **)
E1 58 Left duovalve (water value, A31/1y1, short or open *)
E1 59 Left duovalve (water value, A31/1y1, short or open **)
E1 60 Right duovalve (water value, A31/1y2, short *)
E1 61 Right duovalve (water value, A31/1y2, short **)
E1 62 Right duovalve (water value, A31/1y2, short or open *)
E1 63 Right duovalve (water value, A31/1y2, short or open **)
E1 64 Rear refrigerant shut-off valve (Y67, short *)
E1 65 Rear refrigerant shut-off valve (Y67, short **)
E1 66 Rear refrigerant shut-off valve (Y67, short or open *)
E1 67 Rear refrigerant shut-off valve (Y67, short or open **)
E1 68 Rear tunnel flap vacuum valve (Y67/1, short *)
E1 69 Rear tunnel flap vacuum valve (Y67/1, short **)
E1 70 Rear tunnel flap vacuum valve (Y67/1, short or open *)
E1 71 Rear tunnel flap vacuum valve (Y67/1, short or open **)

You might want to print it out.. It confuses the crap out of me when I try to do it...

Edited by Merc600sec 12/31/2004 1:13 PM
 
#20 ·
Engine Fault codes

And for those of us unfortunate enuff to have need of them..

OBD2 Fault codes...

P0100 Mass or Volume Air Flow Circuit MalfunctionV
P0101 Mass or Volume Air Flow Circuit Range/Performance Problem
P0102 Mass or Volume Air Flow Circuit Low Input
P0103 Mass or Volume Air Flow Circuit High Input
P0104 Mass or Volume Air Flow Circuit Intermittent
P0105 Manifold Absolute Pressure/Barometric Pressure Circuit Malfunction
P0106 Manifold Absolute Pressure/Barometric Pressure Circuit Range/Performance Problem
P0107 Manifold Absolute Pressure/Barometric Pressure Circuit Low Input
P0108 Manifold Absolute Pressure/Barometric Pressure Circuit High Input
P0109 Manifold Absolute Pressure/Barometric Pressure Circuit Intermittent
P0109 Intake Air Temperature Circuit Malfunction
P0111 Intake Air Temperature Circuit Range/Performance Problem
P0112 Intake Air Temperature Circuit Low Input
P0113 Intake Air Temperature Circuit High Input
P0114 Intake Air Temperature Circuit Intermittent
P0115 Engine Coolant Temperature Circuit Malfunction
P0116 Engine Coolant Temperature Circuit Range/Performance Problem
P0117 Engine Coolant Temperature Circuit Low Input
P0118 Engine Coolant Temperature Circuit High Input
P0119 Engine Coolant Temperature Circuit Intermittent
P0120 Throttle/Pedal Position Sensor/Switch A Circuit Malfunction
P0121 Throttle/Pedal Position Sensor/Switch A Circuit Range/Performance Problem
P0122 Throttle/Pedal Position Sensor/Switch A Circuit Low Input
P0123 Throttle/Pedal Position Sensor/Switch A Circuit High Input
P0124 Throttle/Pedal Position Sensor/Switch A Circuit Intermittent
P0125 Insufficient Coolant Temperature for Closed Loop Fuel Control
P0126 Insufficient Coolant Temperature for Stable Operation
P0130 O2 Sensor Circuit Malfunction (Bank 1 Sensor 1)
P0131 O2 Sensor Circuit Low Voltage (Bank 1 Sensor 1)
P0132 O2 Sensor Circuit High Voltage (Bank 1 Sensor 1)
P0133 O2 Sensor Circuit Slow Response (Bank 1 Sensor 1)
P0134 O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 1)
P0135 O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 1)
P0136 O2 Sensor Circuit Malfunction (Bank 1 Sensor 2)
P0137 O2 Sensor Circuit Low Voltage (Bank 1 Sensor 2)
P0138 O2 Sensor Circuit High Voltage (Bank 1 Sensor 2)
P0139 O2 Sensor Circuit Slow Response (Bank 1 Sensor 2)
P0140 O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 2)
P0141 O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 2)
P0142 O2 Sensor Circuit Malfunction (Bank 1 Sensor 3)
P0143 O2 Sensor Circuit Low Voltage (Bank 1 Sensor 3)
P0144 O2 Sensor Circuit High Voltage (Bank 1 Sensor 3)
P0145 O2 Sensor Circuit Slow Response (Bank 1 Sensor 3)
P0146 O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 3)
P0147 O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 3)
P0150 O2 Sensor Circuit Malfunction (Bank 2 Sensor 1)
P0151 O2 Sensor Circuit Low Voltage (Bank 2 Sensor 1)
P0152 O2 Sensor Circuit High Voltage (Bank 2 Sensor 1)
P0153 O2 Sensor Circuit Slow Response (Bank 2 Sensor 1)
P0154 O2 Sensor Circuit No Activity Detected (Bank 2 Sensor 1)
P0155 O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 1)
P0156 O2 Sensor Circuit Malfunction (Bank 2 Sensor 2)
P0157 O2 Sensor Circuit Low Voltage (Bank 2 Sensor 2)
P0158 O2 Sensor Circuit High Voltage (Bank 2 Sensor 2)
P0159 O2 Sensor Circuit Slow Response (Bank 2 Sensor 2)
P0160 O2 Sensor Circuit No Activity Detected (Bank 2 Sensor 2)
P0161 O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 2)
P0162 O2 Sensor Circuit Malfunction (Bank 2 Sensor 3)
P0163 O2 Sensor Circuit Low Voltage (Bank 2 Sensor 3)
P0164 O2 Sensor Circuit High Voltage (Bank 2 Sensor 3)
P0165 O2 Sensor Circuit Slow Response (Bank 2 Sensor 3)
P0166 O2 Sensor Circuit No Activity Detected (Bank 2 Sensor 3)
P0167 O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 3)
P0170 Fuel Trim Malfunction (Bank 1)
P0171 System too Lean (Bank 1)
P0172 System too Rich (Bank 1)
P0173 Fuel Trim Malfunction (Bank 2)
P0174 System too Lean (Bank 2)
P0175 System too Rich (Bank 2)
P0176 Fuel Composition Sensor Circuit Malfunction
P0177 Fuel Composition Sensor Circuit Range/Performance
P0178 Fuel Composition Sensor Circuit Low Input
P0179 Fuel Composition Sensor Circuit High Input
P0180 Fuel Temperature Sensor A Circuit Malfunction
P0181 Fuel Temperature Sensor A Circuit Range/Performance
P0182 Fuel Temperature Sensor A Circuit Low Input
P0183 Fuel Temperature Sensor A Circuit High Input
P0184 Fuel Temperature Sensor A Circuit Intermittent
P0185 Fuel Temperature Sensor B Circuit Malfunction
P0186 Fuel Temperature Sensor B Circuit Range/Performance
P0187 Fuel Temperature Sensor B Circuit Low Input
P0188 Fuel Temperature Sensor B Circuit High Input
P0189 Fuel Temperature Sensor B Circuit Intermittent
P0190 Fuel Rail Pressure Sensor Circuit Malfunction
P0191 Fuel Rail Pressure Sensor Circuit Range/Performance
P0192 Fuel Rail Pressure Sensor Circuit Low Input
P0193 Fuel Rail Pressure Sensor Circuit High Input
P0194 Fuel Rail Pressure Sensor Circuit Intermittent
P0195 Engine Oil Temperature Sensor Malfunction
P0196 Engine Oil Temperature Sensor Range/Performance
P0197 Engine Oil Temperature Sensor Low
P0198 Engine Oil Temperature Sensor High
P0199 Engine Oil Temperature Sensor Intermittent
P0200 Injector Circuit Malfunction
P0201 Injector Circuit Malfunction - Cylinder 1
P0202 Injector Circuit Malfunction - Cylinder 2
P0203 Injector Circuit Malfunction - Cylinder 3
P0204 Injector Circuit Malfunction - Cylinder 4
P0205 Injector Circuit Malfunction - Cylinder 5
P0206 Injector Circuit Malfunction - Cylinder 6
P0207 Injector Circuit Malfunction - Cylinder 7
P0208 Injector Circuit Malfunction - Cylinder 8
P0209 Injector Circuit Malfunction - Cylinder 9
P0210 Injector Circuit Malfunction - Cylinder 10
P0211 Injector Circuit Malfunction - Cylinder 11
P0212 Injector Circuit Malfunction - Cylinder 12
P0213 Cold Start Injector 1 Malfunction
P0214 Cold Start Injector 2 Malfunction
P0215 Engine Shutoff Solenoid Malfunction
P0216 Injection Timing Control Circuit Malfunction
P0217 Engine Overtemp Condition
P0218 Transmission Over Temperature Condition
P0219 Engine Overspeed Condition
P0220 Throttle/Petal Position Sensor/Switch B Circuit Malfunction
P0221 Throttle/Petal Position Sensor/Switch B Circuit Range/Performance Problem
P0222 Throttle/Petal Position Sensor/Switch B Circuit Low Input
P0223 Throttle/Petal Position Sensor/Switch B Circuit High Input
P0224 Throttle/Petal Position Sensor/Switch B Circuit Intermittent
P0225 Throttle/Petal Position Sensor/Switch C Circuit Malfunction
P0226 Throttle/Petal Position Sensor/Switch C Circuit Range/Performance Problem
P0227 Throttle/Petal Position Sensor/Switch C Circuit Low Input
P0228 Throttle/Petal Position Sensor/Switch C Circuit High Input
P0229 Throttle/Petal Position Sensor/Switch C Circuit Intermittent
P0230 Fuel Pump Primary Circuit Malfunction
P0231 Fuel Pump Secondary Circuit Low
P0232 Fuel Pump Secondary Circuit High
P0233 Fuel Pump Secondary Circuit Intermittent
P0234 Engine Overboost Condition
P0235 Turbocharger Boost Sensor A Circuit Malfunction
P0236 Turbocharger Boost Sensor A Circuit Range/Performance
P0237 Turbocharger Boost Sensor A Circuit Low
P0238 Turbocharger Boost Sensor A Circuit High
P0239 Turbocharger Boost Sensor B Malfunction
P0240 Turbocharger Boost Sensor B Circuit Range/Performance
P0241 Turbocharger Boost Sensor B Circuit Low
P0242 Turbocharger Boost Sensor B Circuit High
P0243 Turbocharger Wastegate Solenoid A Malfunction
P0244 Turbocharger Wastegate Solenoid A Range/Performance
P0245 Turbocharger Wastegate Solenoid A Low
P0246 Turbocharger Wastegate Solenoid A High
P0247 Turbocharger Wastegate Solenoid B Malfunction
P0248 Turbocharger Wastegate Solenoid B Range/Performance
P0249 Turbocharger Wastegate Solenoid B Low
P0250 Turbocharger Wastegate Solenoid B High
P0251 Injection Pump Fuel Metering Control "A" Malfunction (Cam/Rotor/Injector)
P0252 Injection Pump Fuel Metering Control "A" Range/Performance (Cam/Rotor/Injector)
P0253 Injection Pump Fuel Metering Control "A" Low (Cam/Rotor/Injector)
P0254 Injection Pump Fuel Metering Control "A" High (Cam/Rotor/Injector)
P0255 Injection Pump Fuel Metering Control "A" Intermittent (Cam/Rotor/Injector)
P0256 Injection Pump Fuel Metering Control "B" Malfunction (Cam/Rotor/Injector)
P0257 Injection Pump Fuel Metering Control "B" Range/Performance (Cam/Rotor/Injector)
P0258 Injection Pump Fuel Metering Control "B" Low (Cam/Rotor/Injector)
P0259 Injection Pump Fuel Metering Control "B" High (Cam/Rotor/Injector)
P0260 Injection Pump Fuel Metering Control "B" Intermittent (Cam/Rotor/Injector)
P0261 Cylinder 1 Injector Circuit Low
P0262 Cylinder 1 Injector Circuit High
P0263 Cylinder 1 Contribution/Balance Fault
P0264 Cylinder 2 Injector Circuit Low
P0265 Cylinder 2 Injector Circuit High
P0266 Cylinder 2 Contribution/Balance Fault
P0267 Cylinder 3 Injector Circuit Low
P0268 Cylinder 3 Injector Circuit High
P0269 Cylinder 3 Contribution/Balance Fault
P0270 Cylinder 4 Injector Circuit Low
P0271 Cylinder 4 Injector Circuit High
P0272 Cylinder 4 Contribution/Balance Fault
P0273 Cylinder 5 Injector Circuit Low
P0274 Cylinder 5 Injector Circuit High
P0275 Cylinder 5 Contribution/Balance Fault
P0276 Cylinder 6 Injector Circuit Low
P0277 Cylinder 6 Injector Circuit High
P0278 Cylinder 6 Contribution/Balance Fault
P0279 Cylinder 7 Injector Circuit Low
P0280 Cylinder 7 Injector Circuit High
P0281 Cylinder 7 Contribution/Balance Fault
P0282 Cylinder 8 Injector Circuit Low
P0283 Cylinder 8 Injector Circuit High
P0284 Cylinder 8 Contribution/Balance Fault
P0285 Cylinder 9 Injector Circuit Low
P0286 Cylinder 9 Injector Circuit High
P0287 Cylinder 9 Contribution/Balance Fault
P0288 Cylinder 10 Injector Circuit Low
P0289 Cylinder 10 Injector Circuit High
P0290 Cylinder 10 Contribution/Balance Fault
P0291 Cylinder 11 Injector Circuit Low
P0292 Cylinder 11 Injector Circuit High
P0293 Cylinder 11 Contribution/Balance Fault
P0294 Cylinder 12 Injector Circuit Low
P0295 Cylinder 12 Injector Circuit High
P0296 Cylinder 12 Contribution/Range Fault
P0300 Random/Multiple Cylinder Misfire Detected
P0301 Cylinder 1 Misfire Detected
P0302 Cylinder 2 Misfire Detected
P0303 Cylinder 3 Misfire Detected
P0304 Cylinder 4 Misfire Detected
P0305 Cylinder 5 Misfire Detected
P0306 Cylinder 6 Misfire Detected
P0307 Cylinder 7 Misfire Detected
P0308 Cylinder 8 Misfire Detected
P0309 Cylinder 9 Misfire Detected
P0311 Cylinder 11 Misfire Detected
P0312 Cylinder 12 Misfire Detected
P0320 Ignition/Distributor Engine Speed Input Circuit Malfunction
P0321 Ignition/Distributor Engine Speed Input Circuit Range/Performance
P0322 Ignition/Distributor Engine Speed Input Circuit No Signal
P0323 Ignition/Distributor Engine Speed Input Circuit Intermittent
P0325 Knock Sensor 1 Circuit Malfunction (Bank 1 or Single Sensor)
P0326 Knock Sensor 1 Circuit Range/Performance (Bank 1 or Single Sensor) P0327 Knock Sensor 1 Circuit Low Input (Bank 1 or Single Sensor)
P0328 Knock Sensor 1 Circuit High Input (Bank 1 or Single Sensor)
P0329 Knock Sensor 1 Circuit Intermittent (Bank 1 or Single Sensor)
P0330 Knock Sensor 2 Circuit Malfunction (Bank 2)
P0331 Knock Sensor 2 Circuit Range/Performance (Bank 2)
P0332 Knock Sensor 2 Circuit Low Input (Bank 2)
P0333 Knock Sensor 2 Circuit High Input (Bank 2)
P0334 Knock Sensor 2 Circuit Intermittent (Bank 2)
P0335 Crankshaft Position Sensor A Circuit Malfunction
P0336 Crankshaft Position Sensor A Circuit Range/Performance
P0337 Crankshaft Position Sensor A Circuit Low Input
P0338 Crankshaft Position Sensor A Circuit High Input
P0339 Crankshaft Position Sensor A Circuit Intermittent
P0340 Camshaft Position Sensor Circuit Malfunction
P0341 Camshaft Position Sensor Circuit Range/Performance
P0342 Camshaft Position Sensor Circuit Low Input
P0343 Camshaft Position Sensor Circuit High Input
P0344 Camshaft Position Sensor Circuit Intermittent
P0350 Ignition Coil Primary/Secondary Circuit Malfunction
P0351 Ignition Coil A Primary/Secondary Circuit Malfunction
P0352 Ignition Coil B Primary/Secondary Circuit Malfunction
P0353 Ignition Coil C Primary/Secondary Circuit Malfunction
P0354 Ignition Coil D Primary/Secondary Circuit Malfunction
P0355 Ignition Coil E Primary/Secondary Circuit Malfunction
P0356 Ignition Coil F Primary/Secondary Circuit Malfunction
P0357 Ignition Coil G Primary/Secondary Circuit Malfunction
P0358 Ignition Coil H Primary/Secondary Circuit Malfunction
P0359 Ignition Coil I Primary/Secondary Circuit Malfunction
P0360 Ignition Coil J Primary/Secondary Circuit Malfunction
P0361 Ignition Coil K Primary/Secondary Circuit Malfunction
P0362 Ignition Coil L Primary/Secondary Circuit Malfunction
P0370 Timing Reference High Resolution Signal A Malfunction
P0371 Timing Reference High Resolution Signal A Too Many Pulses
P0372 Timing Reference High Resolution Signal A Too Few Pulses
P0373 Timing Reference High Resolution Signal A Intermittent/Erratic Pulses
P0374 Timing Reference High Resolution Signal A No Pulses
P0375 Timing Reference High Resolution Signal B Malfunction
P0376 Timing Reference High Resolution Signal B Too Many Pulses
P0377 Timing Reference High Resolution Signal B Too Few Pulses
P0378 Timing Reference High Resolution Signal B Intermittent/Erratic Pulses
P0379 Timing Reference High Resolution Signal B No Pulses
P0380 Glow Plug/Heater Circuit "A" Malfunction
P0381 Glow Plug/Heater Indicator Circuit Malfunction
P0382 Exhaust Gas Recirculation Flow Malfunction
P0385 Crankshaft Position Sensor B Circuit Malfunction
P0386 Crankshaft Position Sensor B Circuit Range/Performance
P0387 Crankshaft Position Sensor B Circuit Low Input
P0388 Crankshaft Position Sensor B Circuit High Input
P0389 Crankshaft Position Sensor B Circuit Intermittent
P0400 Exhaust Gas Recirculation Flow Malfunction
P0401 Exhaust Gas Recirculation Flow Insufficient Detected
P0402 Exhaust Gas Recirculation Flow Excessive Detected
P0403 Exhaust Gas Recirculation Circuit Malfunction
P0404 Exhaust Gas Recirculation Circuit Range/Performance
P0405 Exhaust Gas Recirculation Sensor A Circuit Low
P0406 Exhaust Gas Recirculation Sensor A Circuit High
P0407 Exhaust Gas Recirculation Sensor B Circuit Low
P0408 Exhaust Gas Recirculation Sensor B Circuit High
P0410 Secondary Air Injection System Malfunction
P0411 Secondary Air Injection System Incorrect Flow Detected
P0412 Secondary Air Injection System Switching Valve A Circuit Malfunction
P0413 Secondary Air Injection System Switching Valve A Circuit Open
P0414 Secondary Air Injection System Switching Valve A Circuit Shorted
P0415 Secondary Air Injection System Switching Valve B Circuit Malfunction
P0416 Secondary Air Injection System Switching Valve B Circuit Open
P0417 Secondary Air Injection System Switching Valve B Circuit Shorted
P0418 Secondary Air Injection System Relay "A" Circuit Malfunction
P0419 Secondary Air Injection System Relay "B" Circuit Malfunction
P0420 Catalyst System Efficiency Below Threshold (Bank 1)
P0421 Warm Up Catalyst Efficiency Below Threshold (Bank 1)
P0422 Main Catalyst Efficiency Below Threshold (Bank 1)
P0423 Heated Catalyst Efficiency Below Threshold (Bank 1)
P0424 Heated Catalyst Temperature Below Threshold (Bank 1)
P0430 Catalyst System Efficiency Below Threshold (Bank 2)
P0431 Warm Up Catalyst Efficiency Below Threshold (Bank 2)
P0432 Main Catalyst Efficiency Below Threshold (Bank 2)
P0433 Heated Catalyst Efficiency Below Threshold (Bank 2)
P0434 Heated Catalyst Temperature Below Threshold (Bank 2)
P0440 Evaporative Emission Control System Malfunction
P0441 Evaporative Emission Control System Incorrect Purge Flow
P0442 Evaporative Emission Control System Leak Detected (small leak)
P0443 Evaporative Emission Control System Purge Control Valve Circuit Malfunction
P0444 Evaporative Emission Control System Purge Control Valve Circuit Open
P0445 Evaporative Emission Control System Purge Control Valve Circuit Shorted
P0446 Evaporative Emission Control System Vent Control Circuit Malfunction
P0447 Evaporative Emission Control System Vent Control Circuit Open
P0448 Evaporative Emission Control System Vent Control Circuit Shorted
P0449 Evaporative Emission Control System Vent Valve/Solenoid Circuit Malfunction
P0450 Evaporative Emission Control System Pressure Sensor Malfunction
P0451 Evaporative Emission Control System Pressure Sensor Range/Performance
P0452 Evaporative Emission Control System Pressure Sensor Low Input
P0453 Evaporative Emission Control System Pressure Sensor High Input
P0454 Evaporative Emission Control System Pressure Sensor Intermittent
P0455 Evaporative Emission Control System Leak Detected (gross leak)
P0460 Fuel Level Sensor Circuit Malfunction
P0461 Fuel Level Sensor Circuit Range/Performance
P0462 Fuel Level Sensor Circuit Low Input
P0463 Fuel Level Sensor Circuit High Input
P0464 Fuel Level Sensor Circuit Intermittent
P0465 Purge Flow Sensor Circuit Malfunction
P0466 Purge Flow Sensor Circuit Range/Performance
P0467 Purge Flow Sensor Circuit Low Input
P0468 Purge Flow Sensor Circuit High Input
P0469 Purge Flow Sensor Circuit Intermittent
P0470 Exhaust Pressure Sensor Malfunction
P0471 Exhaust Pressure Sensor Range/Performance
P0472 Exhaust Pressure Sensor Low
P0473 Exhaust Pressure Sensor High
P0474 Exhaust Pressure Sensor Intermittent
P0475 Exhaust Pressure Control Valve Malfunction
P0476 Exhaust Pressure Control Valve Range/Performance
P0477 Exhaust Pressure Control Valve Low
P0478 Exhaust Pressure Control Valve High
P0479 Exhaust Pressure Control Valve Intermittent
P0480 Cooling Fan 1 Control Circuit Malfunction
P0481 Cooling Fan 2 Control Circuit Malfunction
P0482 Cooling Fan 3 Control Circuit Malfunction
P0483 Cooling Fan Rationality Check Malfunction
P0484 Cooling Fan Circuit Over Current
P0485 Cooling Fan Power/Ground Circuit Malfunction
P0500 Vehicle Speed Sensor Malfunction
P0501 Vehicle Speed Sensor Range/Performance
P0502 Vehicle Speed Sensor Low Input
P0503 Vehicle Speed Sensor Intermittent/Erratic/High
P0505 Idle Control System Malfunction
P0506 Idle Control System RPM Lower Than Expected
P0507 Idle Control System RPM Higher Than Expected
P0510 Closed Throttle Position Switch Malfunction
P0520 Engine Oil Pressure Sensor/Switch Circuit Malfunction
P0521 Engine Oil Pressure Sensor/Switch Circuit Range/Performance
P0522 Engine Oil Pressure Sensor/Switch Circuit Low Voltage
P0523 Engine Oil Pressure Sensor/Switch Circuit High Voltage
P0530 A/C Refrigerant Pressure Sensor Circuit Malfunction
P0531 A/C Refrigerant Pressure Sensor Circuit Range/Performance
P0532 A/C Refrigerant Pressure Sensor Circuit Low Input
P0533 A/C Refrigerant Pressure Sensor Circuit High Input
P0534 Air Conditioner Refrigerant Charge Loss
P0550 Power Steering Pressure Sensor Circuit Malfunction
P0551 Power Steering Pressure Sensor Circuit Range/Performance
P0552 Power Steering Pressure Sensor Circuit Low Input
P0553 Power Steering Pressure Sensor Circuit High Input
P0554 Power Steering Pressure Sensor Circuit Intermittent
P0560 System Voltage Malfunction
P0561 System Voltage Unstable
P0562 System Voltage Low
P0563 System Voltage High
P0565 Cruise Control On Signal Malfunction
P0566 Cruise Control Off Signal Malfunction
P0567 Cruise Control Resume Signal Malfunction
P0568 Cruise Control Set Signal Malfunction
P0569 Cruise Control Coast Signal Malfunction
P0570 Cruise Control Accel Signal Malfunction
P0571 Cruise Control/Brake Switch A Circuit Malfunction
P0572 Cruise Control/Brake Switch A Circuit Low
P0573 Cruise Control/Brake Switch A Circuit High
P0574 Cruise Control Related Malfunction
P0575 Cruise Control Related Malfunction
P0576 Cruise Control Related Malfunction
P0576 Cruise Control Related Malfunction
P0578 Cruise Control Related Malfunction
P0579 Cruise Control Related Malfunction
P0580 Cruise Control Related Malfunction
P0600 Serial Communication Link Malfunction
P0601 Internal Control Module Memory Check Sum Error
P0602 Control Module Programming Error
P0603 Internal Control Module Keep Alive Memory (KAM) Error
P0604 Internal Control Module Random Access Memory (RAM) Error
P0605 Internal Control Module Read Only Memory (ROM) Error
P0606 PCM Processor Fault
P0608 Control Module VSS Output "A" Malfunction
P0609 Control Module VSS Output "B" Malfunction
P0620 Generator Control Circuit Malfunction
P0621 Generator Lamp "L" Control Circuit Malfunction
P0622 Generator Field "F" Control Circuit Malfunction
P0650 Malfunction Indicator Lamp (MIL) Control Circuit Malfunction
P0654 Engine RPM Output Circuit Malfunction
P0655 Engine Hot Lamp Output Control Circuit Malfucntion
P0656 Fuel Level Output Circuit Malfunction
P0700 Transmission Control System Malfunction
P0701 Transmission Control System Range/Performance
P0702 Transmission Control System Electrical
P0703 Torque Converter/Brake Switch B Circuit Malfunction
P0704 Clutch Switch Input Circuit Malfunction
P0705 Transmission Range Sensor Circuit malfunction (PRNDL Input)
P0706 Transmission Range Sensor Circuit Range/Performance
P0707 Transmission Range Sensor Circuit Low Input
P0708 Transmission Range Sensor Circuit High Input
P0709 Transmission Range Sensor Circuit Intermittent
P0710 Transmission Fluid Temperature Sensor Circuit Malfunction
P0711 Transmission Fluid Temperature Sensor Circuit Range/Performance
P0712 Transmission Fluid Temperature Sensor Circuit Low Input
P0713 Transmission Fluid Temperature Sensor Circuit High Input
P0714 Transmission Fluid Temperature Sensor Circuit Intermittent
P0715 Input/Turbine Speed Sensor Circuit Malfunction
P0716 Input/Turbine Speed Sensor Circuit Range/Performance
P0717 Input/Turbine Speed Sensor Circuit No Signal
P0718 Input/Turbine Speed Sensor Circuit Intermittent
P0719 Torque Converter/Brake Switch B Circuit Low
P0720 Output Speed Sensor Circuit Malfunction
P0721 Output Speed Sensor Range/Performance
P0722 Output Speed Sensor No Signal
P0723 Output Speed Sensor Intermittent
P0724 Torque Converter/Brake Switch B Circuit High
P0725 Engine Speed input Circuit Malfunction
P0726 Engine Speed Input Circuit Range/Performance
P0727 Engine Speed Input Circuit No Signal
P0728 Engine Speed Input Circuit Intermittent
P0730 Incorrect Gear Ratio
P0731 Gear 1 Incorrect ratio
P0732 Gear 2 Incorrect ratio
P0733 Gear 3 Incorrect ratio
P0734 Gear 4 Incorrect ratio
P0735 Gear 5 Incorrect ratio
P0736 Reverse incorrect gear ratio
P0740 Torque Converter Clutch Circuit Malfuction
P0741 Torque Converter Clutch Circuit Performance or Stuck Off
P0742 Torque Converter Clutch Circuit Stuck On P0743 Torque Converter Clutch Circuit Electrical
P0744 Torque Converter Clutch Circuit Intermittent
P0745 Pressure Control Solenoid Malfunction
P0746 Pressure Control Solenoid Performance or Stuck Off
P0747 Pressure Control Solenoid Stuck On
P0748 Pressure Control Solenoid Electrical
P0749 Pressure Control Solenoid Intermittent
P0750 Shift Solenoid A Malfunction
P0751 Shift Solenoid A Performance or Stuck Off
P0752 Shift Solenoid A Stuck On
P0753 Shift Solenoid A Electrical
P0754 Shift Solenoid A Intermittent
P0755 Shift Solenoid B Malfunction
P0756 Shift Solenoid B Performance or Stuck Off
P0757 Shift Solenoid B Stuck On
P0758 Shift Solenoid B Electrical
P0759 Shift Solenoid B Intermittent
P0760 Shift Solenoid C Malfunction
P0761 Shift Solenoid C Performance or Stuck Off
P0762 Shift Solenoid C Stuck On
P0763 Shift Solenoid C Electrical
P0764 Shift Solenoid C Intermittent
P0765 Shift Solenoid D Malfunction
P0766 Shift Solenoid D Performance or Stuck Off
P0767 Shift Solenoid D Stuck On
P0768 Shift Solenoid D Electrical
P0769 Shift Solenoid D Intermittent
P0770 Shift Solenoid E Malfunction
P0771 Shift Solenoid E Performance or Stuck Off
P0772 Shift Solenoid E Stuck On
P0773 Shift Solenoid E Electrical
P0774 Shift Solenoid E Intermittent
P0780 Shift Malfunction
P0781 1-2 Shift Malfunction
P0782 2-3 Shift Malfunction
P0783 3-4 Shift Malfunction
P0784 4-5 Shift Malfunction
P0785 Shift/Timing Solenoid Malfunction
P0786 Shift/Timing Solenoid Range/Performance
P0787 Shift/Timing Solenoid Low
P0788 Shift/Timing Solenoid High
P0789 Shift/Timing Solenoid Intermittent
P0790 Normal/Performance Switch Circuit Malfunction
P0801 Reverse Inhibit Control Circuit Malfunction
P0803 1-4 Upshift (Skip Shift) Solenoid Control Circuit Malfunction
P0804 1-4 Upshift (Skip Shift) Lamp Control Circuit Malfunction
 
#21 ·
Adaptive System Fuel Injection

An article I found whilst reasearching my problems

I've always loved the puzzle. Check Engine warning lights have become an everyday chore for me over the last five years. It's a challenge that extends my interest and creativity in the auto service profession.

Before I deal with some specific Mercedes-Benz faults that I've researched, I must say that the ability to really solve these puzzles in any car depends upon two important factors. First, and most important, is a working knowledge of the system involved and the specific nature of the fault that's been recorded. This means knowing what conditions must exist to set up the evaluation that failed, as well as the nature of the test that failed. The second factor is the nature of the tooling available for testing the criteria being faulted.

In a relatively short magazine article, I certainly can't teach the systems, but I can show a number of techniques that can change 70-80% of Mercedes Check Engine lights into money-making repairs, that will boost customer satisfaction in the process.

ADAPTION CAPABILITIES
Probably my favorite fault codes are the ones that deal with the adaptation capabilities of the system. In my CIS days, we (as technicians) centered the system so that electronic feedback control could work equally well correcting both rich and lean. In these cars, the adaptation fault codes were O2 sensor codes. The controller recognized when the O2 sensor was stuck at the rich or lean stop. Being stuck against a stop usually wasn't the O2 sensor's fault and the problem always boiled down to a mechanical mixture issue. With the change to electronic injector control (done to facilitate single cylinder cut-off necessary for future OBD II), the ability to center the mixture range was built into the software. In these first systems, LH and HFM, the diagnostic controls necessary for U.S. emissions control were not yet incorporated into the engine management hardware or software. These cars had their Check Engine light controlled by the diagnostic module (DM).

So, in the late '90s, we started seeing the first of the real fun adaptation codes on the DM. There's an M-B service bulletin applying to the Jacksonville Zone (I live 80 miles from Jacksonville, FL). It talks about the Code 19 Check Engine light and, while the concept of adaptation isn't mentioned, it says that a new controller is the solution. This code, if read from any simple description, blames the injectors. But the real problem is that the system has reached its adaptive limit. In the Jacksonville case with 119 model V8 engines, the lower partial adaptation and maybe the upper partial adaptation would bump against 0.85. This meant that the original fuel calculation of 1.00 had been reduced 15% to 0.85 under one or both of the measuring criteria. The way Mercedes repaired this problem was to increase the software's corrective capabilities. In cars that I've repaired with the new software, the mixture stabilizes at around 0.81 after two years (my oldest test case).

On all Mercedes vehicles with adaptation codes, it's necessary to reset the adaptation after repairs to the original 1.00 value. On the early LH and HFM systems, the relearning after such re-adaptations can take weeks and is not very usable to diagnostics unless you have a chassis dyno. For perspective, I want to explain a short research project I did on a 600SEL that had the estimate of both controllers to solve the Code 19 problem. The lower partial load correction was at 0.85 on one bank and 0.89 on the other. The upper partial was above 0.90 on both banks. At first, I readapted and drove the car. I gave it back to the customer, and it took two weeks to readapt to the point of setting the light. I finally put the car on the dyno and did the relearn using the aid of the scanner.

After doing the adaptation a few times, it became apparent why it took so long on the street. The program requires achievement of a certain condition: Load 40-80kg/hr; rpm 1,600-2,200. Once stable at that condition (easy to achieve on a dyno), the car's adaptation program goes active and it requires holding those conditions for maybe 10 seconds in lower partial. If you try to recreate these conditions on the road, it's almost impossible except when driving against exactly the right angle hill. At the load stated, the car accelerates unless it's on the right-size hill and quickly exceeds the rpm criteria, stopping the adaptation process.

We did a number of parts swaps, as the system on this 12 cylinder is actually two 6-cylinder systems. The swap that won was changing the air flow meters. We found that no matter where we put one of the units, we always got a 0.85 lower partial after the relearn. A new unit saved a bunch of money, for the moment.

For the moment, as Mercedes eventually found out, 15% was too little built-in correction, and all the cars since the ME engine management system have had 32% correction capabilities from 0.68 to 1.32. All replacement controllers for early LH and HFM systems also come with the new capabilities, solving the problem on early cars. You must recognize that the real problem in all these instances is that the mixture has changed from the standard. In the case of a 0.85 car, the system is subtracting 15% fuel to keep the range of correction in the center (remember what we did with CIS!). This brings me to the current, most common code going: The P0170/P0173 adaptive limits code.

ADAPTIVE LIMITS CODE
On the latest M-Bs, this most common code usually means one of two types of Air Mass Meter (AMM) failure. The first type, AMM failure, results in failure of the partial load multiplicative correction at 1.32. This means they are correcting a lean mixture by adding 32% more fuel to the original 1.00 calculation.

The second type of failure is more interesting. In this failure the output of the AMM is not linearly skewed as in the first. The partial load will probably be in the range of 1.10 to 1.20 or so. This correction is multiplicatively applied to all range of fuel control from cold start to idle. At idle, this AMM runs fairly accurately and, as a result, the Closed Throttle Position (CTP) additive correction has to repair the rich-running condition caused by the multiplicative correction. It does this with an additive correction of up to -1.0 ms (removing fuel). The limits of correction here are -1 ms to +1 ms.

Most of the P0170/0173 codes are on V6 and V8 models and AMMs are the common problem, but the two codes refer to right and left bank and they can be used to evaluate air leaks. One should always look to air leaks in cases of positive additive CTP corrections.

MISFIRE CODES
Leaving fuel adaptation, I need to make a small mention of another group of fairly unique Mercedes attributes in adaptation: Throttle and sensor ring. Mercedes uses something it calls sensor ring adaptation to compensate for regular deviations of crankshaft acceleration rate that appear at particular load and rpm blocks. This crankshaft acceleration rate is what is evaluated for misfire determination, so the adaptation is done to prevent driveshaft, flywheel, motor mount and other rhythmic vibrations from distorting this calculation. I suspect that many of the misfires of unknown origin come from mistakes the software makes in identifying a misfire, which then, of course, shuts down fuel at that injector, assuring there is a misfire until the key is cycled.

My wife may have had such a condition with her in-warranty ML320. She had a misfire on cold start nearly every day and would have to shut off the car and restart it to remove the misfire, and a misfire code would be set. It went to the dealer and the first repair was to readapt the sensor ring. This made the problem go away for more than two weeks. At the next visit, they replaced the ME control unit. I had looked at the load/rpm sensor ring blocks both before and after the new controller was installed, and the number of blocks was increased by at least three times from four to maybe 16 with the new software on the new controller. I believe that during the heavy, low-speed turning in reverse, the normal judder of early M-B 4WD was being misinterpreted as a misfire.

Throttle adaptation is one area that is fairly simple, but because M-B uses throttle control for idle control, cruise control and drive-by-wire, it's very important when evaluating any of these problems to be sure that the throttle is adapted. It's a PID on most scanners and is also a menu item under adaptations of most scanners. All that is necessary with most scanners is to erase the old adaptation and relearn with the key on and engine off for 30 seconds, followed by the key being switched off for 10 seconds.

There are a number of simple things to look for with Mercedes misfires. My first advice is to be sure no one has erased the adaptations on one of those P0170 cars. When they lose that 1.32 adaptation and then run at 1.00, they will set random misfire codes. Remember that most specific single-cylinder misfires (P030x) are caused by the resistors at the spark plugs, including the ones located below coils. They can be so common, intermittent and hard to view with a scope, that we've started replacing the three beneath the coils (p/n 000 156 36 42) when changing spark plugs on HFM motors (see Fig. 1). We see plenty of coil problems and usually achieve a diagnosis by moving the coil to another cylinder.

The P04xx group of codes probably are the gravy of the emissions business. From EGR, to secondary air, to evaporative emissions control, these codes represent the testing of emissions systems that mostly have no driveability performance effect. These are the codes the customers hate. In my small window on the trade, it appears that the pieces designed to do monitor tests are not designed to perform as the safety and hardware items have been. Most of these codes are for failing two tests over time. The tests are often run only once a drive cycle, so it takes a while for them to get run and, thus, the light can stay off for long periods of time with the problem still existing.

All of these fault codes are best tested with the activation programs built into proper scanners. In the case of EVAP codes P0440 through P0455, Mercedes uses a vacuum-style test of the system for vapor leaks and current supply calculations from internal dropping resistors to evaluate solenoid control. In normal operation, the engine controller pulses the purge valve in varying amounts, pulling air over the fuel vapor absorbed in the charcoal canister, moving it into the engine for burning.

To evaluate the system for leaks, a cap is placed over the charcoal canister air inlet and a vent valve placed there is closed. Closing the canister seals the system, and the subsequent opening of the purge valve allows the tank system to be placed under a small vacuum. The test for this system is straightforward with the help of a scanner. The scanner needs to interpret the tank pressure and be able to close the vent valve. When run by a scanner, you are told to pull no more than 25 millibar (mb) on the system and then watch the decay over time. It can't drop more than 5 mb in 60 seconds.

I built a tool based on this design that's posted on iATN (see Fig. 2). Based on a 5V-powered GM tank pressure sensor, we made a connection through a new gas cap (see Fig. 3). I built this tool because even though M-B scanners will use a manually run test, BMWs and Volvos use a forced monitor with pass/fail results. In these cars, the test is run and, if it fails, there are diagnostics. But if it passes, you have no help. The tool allows you to watch what is happening during a forced monitor or a manual one such as what M-B uses.

In Fig. 4, we have a graphing multimeter record of a manual test we performed on a SLK230. The first ramp is the period where the vacuum is created in the tank. It is pulled by a hand vacuum pump at the purge line to 25 mb, as determined by the scanner (see Fig. 5). The peak is 25.4 mb. At the peak, the hand pump has stopped and the leak criteria is that the system must not leak more than 5 mb in 60 seconds. The increased leak rate slope starts when the scanner reopens the vent valve. At that point, the scanner had 21.3 mb. From the graph, you can see that the time interval is well over 60 seconds and the drop is 4.1 mb, which is well within the criteria.

In the second graphing multimeter image (see Fig. 6), a 0.040-in. hole has been drilled into a piece of hard plastic vacuum line placed between the hand pump and the purge line. It was originally covered with tape and the vent valve closed and the system hand- pumped to a little over 25 mb again. The small down slope is the natural system decay, and the larger slope is after the tape is removed. The slope of the line now is way beyond the failure spec of 5 mb per 60 seconds.

This imaging gives a context to the testing of small leaks. The testing of large leaks is very seldom an actual leak. The car looks at the upward slope as in the GMM images. The slope of that section depends on the rate of hand pumping in these tests. When the car runs the test, the test value must be achieved in a certain time. If a leak is too big, then the pressure in the tank never rises or rises too slowly. The SLK we were testing had a large P0455 leak code. The problem was that the line coming out of the charcoal canister to the tanks was plugged. There was no leak but, because the tank never saw the vacuum that was applied, the assumption was made in fault analysis that all of the vacuum had leaked rather than make it to the tank. We've also found the purge valve itself to cause large leak codes due to being plugged with charcoal or not opening at all.

While working on the SLK, we used our new toy to mimic another uniquely Mercedes purge test. This test is not used on the SLK, but we set it up for view. On many mid-'90s cars, M-B had both an Air Mass Meter and a MAP sensor installed. During purge testing, the MAP sensor was shunted to the purge line from manifold vacuum by a switchover valve. During purge, the controller looked for pulses on the MAP signal in frequency with the purge flow duty cycle. In Fig. 7, we've mounted the GM tank sensor tool into the line after the purge valve and the output is channel 2 on the scope pattern. Channel one is the signal to the purge valve (see Fig. 8). This mechanism for faulting the purge valve is used on 202 models with HFM and 129 models of ME, using 104, 119 and 120 motors and maybe others.

TESTING FOR OTHER CODES
Secondary air codes are another type of code made simpler with the use of a good scanner. Secondary air injection is used for burning the rich mixtures of cold start and for heating both the O2 sensors and the catalyst. They have to be shut off before closed-loop fuel control can take place. M-B uses an intrusive test with the O2 sensors to evaluate the "causal chain" of secondary air. Causal chain is a M-B text term that baffled me for a time. I've now come to the conclusion that this phrase means that a fault in causal chain means that everything necessary for a result to happen, happened, but the result didn't happen. In the case of secondary air injection, it means that the air pump was turned on and the check valve was directed open, but nothing happened.

To make this evaluation, the car and scanner causes the air pump and check valve to work on a car in closed loop and the O2 sensor voltage must reach either 80 mV on early cars or 40 mV on later cars within a certain time span. I used my scope to verify such activity on a 1999 E320. I did cheat and use the scanner for activation, but I backprobed the O2 sensor for the output. I swear this is a real scope pattern of the test (see Fig. 9). It almost looks too perfect.

Most M-B problems with secondary air originate in the vacuum controls and sometimes the electrical components of the pumps (including clutches on belt-driven pumps) and weak O2 sensors. The real nasty ones are the restricted passageway causal chain codes. These are happening mostly in 119 engines.

A quick way to determine if the reduced capability of a system is O2 sensor or secondary air flow-related, is to first run the test above. If you get only a drop to 100 mV before fuel correction moves it back up, try as a second test to monitor the O2 sensor and crack the line to the brake booster. With a good sensor, the value will pass the 40 or 80 mV criteria, without even making the car run bad when the vacuum line is cracked.

At this time, I haven't heard of any way to clear the restricted secondary air passages in 119 heads except by head removal, making this the all-time most expensive fault code for a failure of a non-performance test.

EGR codes are fairly simple on most M-Bs. They are often vacuum control problems, but most commonly the pipes that carry the EGR into the intake get clogged. One interesting note about these clogs is that the clog is not from EGR gasses. The clogs come from oily PCV vapors in the intake baking onto the pipe carrying the EGR gasses. So when looking for the restriction, start at the intake end. On 104 motors, this is the common place (see Fig. 10). On 112 and 113 motors, there is a stainless pipe that enters the intake in the middle rear. It must be removed and then can be easily cleaned.

A proper scanner again gives the basics in testing through activation. If it activates with noticeable motor effect and still sets a code, the chances are high that the line is restricted. One can do a similar test by teeing into the vacuum to the EGR and driving. EGR will take place at most throttle settings other than closed and full. Once vacuum control is verified, a vacuum placed on the valve with the engine running at idle finishes the effect of the scanner test. If it passes both tests, and still sets a code, look to the pipe.

There are lots of other codes but space is short, so the last code I want to talk about is another strictly M-B code. It is the upshift delay codes P1700 and P1701. These codes would only apply to the mechanically controlled automatic transmissions used before 1996. Those transmissions used a throttle pressure cable (control pressure) for determining shift points under various loading. In order to heat the CAT and reduce the cold running time, Mercedes used an electrically controlled, vacuum-operated bellcrank-type lever action to change the capabilities of the control pressure cable. In other words, when cold, vacuum at the switchover valve is switched to a vacuum chamber at the transmission end of the shift cable. There, the actuator movement changes the effective length of the cable. The common problem here is the diaphragm in the actuator element, but testing is simple.

The first test is to see that vacuum is at the switchover valve when running. Next take the line to the transmission from the switchover valve and apply vacuum. In the common failure, the element won't hold vacuum, and you're done with diagnostics.

If the vacuum element holds vacuum, then you must tee into the line at the element and evaluate the vacuum when cold. If there is vacuum at cold running, and a code is present, then evaluate the shift against the criteria. The element is adjustable on the replacements and the cable is always adjustable. A poorly adjusted shift cable adjustment could make the added shift delay not large enough to satisfy the controller.
 
#22 ·
Instrument Cluster Tests

IF you need to run Instrument cluster function test. To do it start engine, then press small button in the center of clock adjusting knob (not the knob itself) for more then 5 seconds. You'll need something like a sharp pencil to do it.
The first test will appear on the outside temperature display. It will read something like 35.1, were 35 is gas in the tank in liters and 1 is the number of the test. To advance to the next step pull the clock knob and turn it clockwise.
There are 9 steps:
1. Gas in the tank in liters
2. Momentary fuel consumption 34.2 is 3.4 liters per hour 2 is step number
3. Engine oil pressure in bar 20.3 means 2.0 bar step 3
4. Engine rpm x 1000
5. Engine oil level 0.5 is OK, 1.5 not OK
6. Activation of the oil pressure, fuel consumption, and fuel tank gauges - needles in the first quarteer of the dial. Indicator 0.6 for step 6
7. Activation of the oil pressure, fuel consumption, and fuel tank gauges - needles in the second quarteer of the dial. Indicator 0.7 for step 7
8. Activation of the fuel consumption, and fuel tank gauges - needles in the third quarteer of the dial. Oil pressure gauge stays in the second quarter. Indicator 0.8 for step 8
9. Activation of the fuel tank gauge, needle in the fourth quarter of the dial, oil pressure remains in the second qurter, fuel consumption remains in the third quarter. Indicator 0.9 for step 9
Done
You need to verify oil pressure reading in step 3 and gauge in steps 6...9
 
#23 ·
HorsePOWER

The first thing to remember is that BHP is not measured on a dyno - only torque, BHP is a factor of torque and engine speed - its just a theoretical calculation

First, power, what do we mean by that?

Well, we usually express power in terms of the amount of time it takes to do a certain amount of work... for example, one horsepower is measured as the amount of work required to lift 33,000 lbs over 1 foot in 1 minute (huh -that's obvious, _). As this is such an obviously Scottish measurement (as James Watt first devised the calculation) , we have a metric equivalent... the metric horse could lift 4,500Kg a metre in a minute... 98.6% of a good British horse. The Europeans decided to call it a PS (Pferde Starke - German for Horse power&#33instead of an HP to cover their shame. Also, in the newfangled metric system, 1hp is the equivalent of 746 Watts of electrical power. So, to recap briefly:

1 HP = Roughly the amount of work a horse can do lifting coal up a mineshaft, assuming his heart was really in it = 1.014 PS = 0.746 KW - easy huh _

Now we need a way to measure this output - so we use a defined force or "brake" to see how much energy we need to apply to stop it - Hence "Brake Horsepower" - and is defined as it's maximum performance at a certain rpm.


The other thing we babble on about is Torque... Torque is the amount of force applied to turn something multiplied by the distance from the axis of it's rotation... sounds all weird, until you realise that we use the engine to rotate the front wheel, so torque is something that would be nice to calculate. Something interesting is that 1hp is 550ft/lbs of torque per second.

Now, it's fairly easy to measure torque... this is where the dyno comes in, and we calculate horsepower from an engine's torque output multiplied by the revs...


A dynomometer is just a heavy drum (brake), an accelerometer and a computer... if you know the weight of the drum, and you know how fast it's being accelerated, you can calculate the torque that must be being applied to the drum. What you also want to take into account are the frictional losses on the drum, and the air temperature at the time (which is why you'll see air temperature, pressure and a correction factor calculated by the software... as air temperature goes up, so the effective power output goes down, so the correction factor has to go up to normalise this).

Taking a Dyno Run
( As used today at PTS - differs slightly if they use an inductive loop)

So, to measure torque, we strap the car to the dyno, start it up and run it up in the gears to 3000RPM the dyno operator holds the car at a steady 3000 for 6-7 seconds and the dyno learns the road speed for that car at 3k. ( Some dynos use an inductive loop to accurately measure RPM - but the rev counter method works fine for most modern cars) - now with a given road speed the RPM can be calculated.
... cars tend to do their power runs in 4th gear, as it's the best gear for acceleration at speed and less chance of the wheels slipping, as the calculation errors get smaller the bigger the numbers are. 4th is used because on cars these days 5th gear tend to be a bit of an overdrive.
The throttle is gently floored, and the dyno slowly allows the speed of the engine to increase - this measures the torque of the engine. When the engine reaches maximum RPM, the operator puts the car in neutral, and allows the wheels to decelerate of their own accord - this measures the losses of the transmission,driveshafts,bearings brakes (if they are sticking) and tyres

Now here comes the maths

BHP = Torque (lbft) x RPM
_ _ _ _ -------------------
_ _ _ _ _ _ _ _ 5252

This means that BHP is always equal to torque at 5252rpm _- if its not then there is something wrong!

Now using Pauls results from today we get max power of 169.3BHp @ 7869RPM but 115.0lbft of Torque. The important factor here is that it makes its maximum power at nearly 8000rpm!

Andy Blower made more torque 123.5lb/ft - therefore it must be quite a bit more powerful right? - WRONG ! - he made his max figure at 7309rpm - and as BHP is proportional to speed and his engine was making its torque at a lower RPM value - he gets 169.4 BHP - a whole 0.1bhp more _

Shirish made 129.8lb/ft at 7466rpm - which equates to 170.4BHP

So now we have 115, 123.5 and 129lb/ft of torque - all at different engine speeds - All giving an output of 170BHP give or take a little bit

The moral of this essay is - it is better to make torque at high RPM for a screamer! - and thats why beause Hondas rev so high they produce the power!

I realise I've forgotten an important part of the calculation _

Where did the 5252 figure come from ?

As discussed what we actually measure is torque, expressed in ft/lb, and then we calculate actual horsepower by converting the twisting force of torque into the work units of horsepower.

Visualize a one pound weight, one foot from a fulcrum on an "invisible weightless" bar. If we rotate that weight for one full revolution against a one pound resistance, we have moved it a total of 6.2832 feet (pi times a two foot circle), and, we have done 6.2832 foot pounds of work.

OK. Remember Watt? He said that 33,000 foot pounds of work per minute was equivalent to one horsepower. If we divide the 6.2832 foot pounds of work we've done per revolution of the weight into 33,000 foot pounds, we come up with the fact that we have to rotate that weight at the rate of 5,252 revolutions per minute in order to do 33,000 foot pounds per minute of work, and thus do work at the equivalent rate of one horsepower.
Therefore, the following formula applies for calculating horsepower from a torque measurement:

Horsepower = ( Torque * RPM ) / 5252

Thats where the 5252 comes from


Torque is only half the story. While torque is the force created, it doesn't account for the importance of revs.
Imagine trying to remove a wheel nut from a car with a standard wheelbrace and all the torque you could produce can't loosen the "Kwik fit special" airgunned super tightened wheel bolts. You apply lots of force, i.e. torque, but you still can't generate any rpm. Therefore nothing is accomplished, no power generated despite your cursing and kicking. So - Without rpm, torque is useless!

Two engines may make 125 foot/pounds of torque, but if one is a FixOrRepairDaily turning at 5,000 rpm and another is a Honda turning at 10,000 rpm, the Honda is doing more work than the FixOrRepairDaily, therefore generating more power.

HP = Torque x RPM / 5252

so the FixOrRepairDaily makes 125*5000 / 5252 = 119HP,
but the Honda makes 125*10000 / 5252 = 238HP_
 
#24 ·
Key Pro-game-ing..??

19/97-4 GROUP 82 - MODEL 140, INTRODUCTION OF ROLLING
CODE UNIVERSAL TRANSMITTER: As of vin # A367861 with production
date of 03/27/97, all Model 140 vehicles are now equipped with a garage
door transmitter which is capable of functioning with rolling code garage
door openers. The new style transmitter can be identified by amber
LED's as opposed to red LED's on the previous version. The
programming procedure has also changed, and is listed below. A
Service Information on this topic is being prepared and will be released
shortly. PROGRAMMING THE UNIVERSAL TRANSMITTER: 1) Prepare
for programming by erasing all three factory defaults by holding down
the two outside buttons until the light begins to flash (20-30 seconds).
Release both buttons. 2) Hold the end of the hand-held transmitter
against the universal transmitter keeping the light on the Universal
Transmitter in view. 3) Using both hands, push the hand-held transmitter
button and the desired button to be programmed on the universal
transmitter. Hold down both buttons until the light on the universal
transmitter flashes, first slowly and then rapidly. When the light flashes
rapidly, both buttons may be released. (The rapid flashing light indicates
successful programming.) 4) Repeat steps 2 and 3 to program the
remaining channels (if necessary).
If after repeated attempts, you are unable to successfully program the
transmitter, the garage door opener may be equipped with "rolling code"
security. This can be established by either of the following: a) The
hand-held transmitter appears to program the universal transmitter, but
thereafter the vehicle's universal transmitter does not activate the garage
door. OR b) The garage door opener was manufactured after 1995. To
train a garage door opener receiver with the rolling code feature, follow
these steps (the aid of a second person is suggested): 1) Locate the
training button on the garage door opener receiver (this is the opener unit
itself). Location and color of the button varies by manufacturer.
Reference the garage door opener manual or call 1-800-355-3515. 2)
Press the training button on the garage door opener receiver until the
light next to the button begins to flash (1-2 seconds). 3) Press the
programmed universal transmitter button in the vehicle until the training
light on the garage door receiver turns solid (1-2 seconds). Release the
button on the universal transmitter, and then re-press which turns off the
training light. Confirm the operation of the garage door by pressing once
again
 
#26 ·
Self leveling

IF your ADS system might be a little slow to respond some of them are if they are not used often or they have switched themselves off to protect things... when you have filled with clean oil try lifting the back from the diff housing with a trolley jack,so tyres just touching floor(do this on flat surface)whilst running engine and switch ADS on and off a few times.. then drop and lift a few times.5times front each side 5times back switching between hard5 and soft5. check the colour of the oil.. and the magnet in the reservoir .. see if you have muck.. will flush system round a bit give it somthing to do..last time should remain HIGH for some time and settle slowly..then you can do the trunk test.. get two of your larger friends to climb into the back and watch to see if the self levellig system takes you back to level again..should be less than 30 seconds and then if the ride seems a bit harsh to start with.. It might just be it needs to re-learn what to do.. If you have no lights on then I would give it a couple of hundred miles to sort itself out.. then see if you need spheres etc..
 
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