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Center console power outage

6K views 19 replies 5 participants last post by  mrboca 
#1 ·
Parked my 1997 e420 with everything working.

6 hours later I have now power to the center console for window switches, trunk switch, mirror switch and ARS traction control. At the same time I am in the hard coded limp mode with only Reverse and either 1st or 2nd.

In the short time I have owned the car I do not allow open beverages anywhere inside the car so I do not think this is a liquid spill problem. At the suggestion of Raymond- I have thoroughly inspected the front firewall and front floorboards for any signs of water leaking into the car. I have also inspected the rear window, package shelf, trunk, and under the rear seat for water. There are no signs of water leaking anywhere inside the car.

I've read elsewhere that limp mode is most often an electrical problem but I don't find anything that talks about this power outage and limp mode happening at the same time. I can't help but think that the two problems are related. On this assumption, I have searched this site endlessly for a fuse diagram that shows the fuse(s) for any item in the center console or the shifter with no luck. :banghead:

I am waiting for business hours to resume so I can talk to the folks at iCarsoft about why their scanner doesn't talk to my W210 so I can access the ETC trouble codes and eventually clear them.

Until I get my scanner working I hope someone has encountered some or all of these problems that would be kind enough to point me in the right direction. This is my daily driver and it simply must get well soon.

My fondest appreciation for hints tips comments and suggestions.
 
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#2 ·
Hello:)

For 1997 e420 I believe the center console is a group[ of switches connected to the Combination Control module. (CCM). It is the CCM that controls mirrors, window motors and the trunk opening.

So it is possible that one of the fuses to the CCM may have opened. Please check fuses 1 and 2 under the rear seat. Both are 30 amps.

For the limp mode, It is possibly the TRSS module in the shifter (that signals the gear selection) is not receiving power, so the transmission does not know which gear is being selected.

I assume your shifter has is of the old type (PRND->4321) and not PRND +- (touchmatic)

Probably a short has occurred somewhere, I do not know how. When the problem surfaced was it raining ? Were the windows closed ?

Icarsoft will not help you with the transmission code. You need SDS or Carsoft 7.4 / 12 with 38 pin connector.
 
#3 ·
W210 is not compatible for the iCarsoft handheld scanner - W210 is not a model covered by that scanner - don't waste your time "calling" them. W210 is not covered - and it won't be covered - you should have checked covered models before you bought the scanner - and you would have seen W210 is NOT covered - that's that.

A generic scanner can give you basic codes - can the iCarsoft give you basic codes too ? If you have coedes - please post

Now.. you have not posted miles - and you have not posted general history/etc - let's put 1st things 1st.

2) Limp Home Mode - is designed to protect the tranny from more major damage - so let's view that in the positive 1st. If you can pull general codes now - post.. Do forum search/stickies "tranny adapter plug". Need to check communication between tranny and Trans Control Module. For $14 pull and replace "tranny adapter plug with genuine MB/Mopar brand plug only. MB dealer, or Mopar dealer/Crossfire - or Amazon. For $9 buy can of MAF cleaner - pull and clean TCM board and connector in engine compartment - flood clean board both sides - air dry no heat. For under $25 and 1hr your labor comm is now cleaned up.
DON'T trust tranny codes until communication - for $25 get plug/TCM cleaned up - since comm errors can lead you to unnecessary repairs.
Check tranny fluid level (you will need dipstick) - top off as needed. Once you are back and running please consider basic tranny service with ONLY correct fluif and ONLY correct tranny filter. In some cases Limp Home will need to be erased with Star/SDS system - but if you don't correct the cause you will just trip Limp Home again.

3) Center console switches knocked out: PM boca - he loves that stuff.

Overall - you are best served separating Tranny and Console issues - if you left the sunroof open in the rain - please come clean and admit that now.
 
#5 ·
@ fabbrisd1

I have owned the care for about two months. It is garaged every day and most trips are 10 -20 miles 2 or 3 times a week. I’ve had one 400 mile road trip that was without incident and during cold but sunny weather. I also “kick” off the accumulated snow and ice buildup at the wheels before I park in the garage every time I drive the car.

I opened the sunroof one time when inspecting the car for purchase in the seller’s garage and not since. I live in the Inland NW and for the past couple of months we have had temperatures below 35 degrees F and about 18 inches of snow. The care has not been parked outside during any snow storms although has been driven on snow/ice covered streets.

After a trip through the car was last month I did find a sloshing sound that turned out to be water trapped in the driver side rocker panel. Removed clogged drain plugs, drained water, reinstall cleaned plugs. Checked passenger side just for kicks and it was dry. Thanks to this forum I also checked all of the top-side drains and cleared leaves, debris, and years of road grime. Also inspected all interior areas for water infiltration and all were dry. I have no wind noise around any door, window, or sunroof seals and I have not found any water leaks attributed to the car wash.

The car has ~280k miles and has a pretty good maintenance record. I had an Indy oil change just after purchase who told me I was missing the aux fan belt for the electric fan. I replaced the belt.

I have had a few minor problems like fan clutch, blower motor and cabin filter, rear lights, crankcase vent hose, and a window regulator. All repairs were done myself using tips and procedures from this forum with no ongoing problems. I had a dead battery when temps dropped below -0- and on restart from a jump; I got a low voltage on bank 1 O2 sensor error code. Replaced the battery, cleared the code, and have had no other O2 codes or electrical problems until now. I replaced the OEM radio with a Kenwood KDC-X599 installed by a reputable dealer and have not had any problems with the installation.

I have a recurring P0442 code. I have checked all hoses and fittings and performed the pump maintenance found on this site several times. The light comes and goes but does not trigger any other codes. I first attempted to find ETC codes using OBDII and P0442 was the only code listed. I have since learned from this site that ETC codes cannot be read on OBDII.

I have read everything on this forum about limp mode and I understand the theory just fine. I tried the restart procedure for the electronic limp mode but it did not reset the Trans. I am stuck in the hard limp mode with only Reverse and 1st/2nd gear.

I will attempt the “tranny adapter plug” and TCM board and connector clean-up procedures exactly as described and report the results. Am I to understand that if this is the cause of the limp mode I will not need to clear codes?

@ MrBoca –

I have the PRND/4321 shifter and as noted above we are in our winter deep freeze here in the NW. The only water to hit this care since owing is a car wash last month as described above. I will check fuse 1 & 2 and all the rest while I’m at it then report my results.

Both –

Thanks for the info on the iScoft scanner. Instead of calling the firm I’ll package it for return and refund.

Raymond-

Thanks for the welcome and again thank you the behind the scenes support that got me here.

All –

It is nice to have a sensible path to follow rather than endless floundering.

Thank you.
R
 
#6 ·
@ fabbrisd1

Almost forgot – I purchased the trans “dip stick” and have checked the level at 25c and 80c as described elsewhere on this forum using a HF infrared thermometer. Fluid is at correct level on both checks and although kind of dark, it does not smell burnt and there is no evidence of debris or particles in the fluid.

A fluid and filter change is on my to-do list in the Spring although I am hesitant to do the service for fear of rendering the trans dead as happened to me once before on a high mileage US make/model.
 
#8 ·
You have a '99 - there is a "obscure" tranny fault that can happen at mileage like your - in cold weather when parked outside.

Just trying to help - let's see if the tranny comes out of Limp Home after the engine/tranny/cabin are warmed up to normal operating temperature ?

The way to test this:

1) open the center console compartment - make sure the console "vent" is open.

2) start the E-Class - let it idle with cabin set at 72 - let the car idle up until the whole car - including cabin - come up p well into operating temperature - and cabin is at 72. If there is snow on the car - you will see it melting on the hood - and glass.

Once up well into operating temperature - will it shift normally now ?

If this is the case - then it can be your gear recognition switch - due to wear and low temp.

https://www.amazon.com/Mercedes-transmission-Control-Unit-Recognition/dp/B00AHR6PG4
 
#9 ·
@ fabbrisd1

Mine is a 1997 but at this point, I’ll try the “thaw” while I wait for the transmission adapter to arrive on Wednesday.
@mrboca

Tested all of the fuses under the back seat and I have power across every fuse that is “installed.” In the pictures are fuses that are obviously not “installed” and I wonder why they are seated in this position (they all good by continuity test but have no power across the fuse). This is way the car came to me. Is this how spare fuses are mounted?

The console switches are lighted when I turn the headlights on.
 

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#10 ·
Alright, it appears that the CCM powering is fine. I asked about the shifter light because the shifter light, the transmission module, and the the CCM, and the ASR relay share the same grounding terminal, G203, which is located at the right footwell. I was thinking maybe when the Kenwood equipment was installed, the ground terminal is somewhat disturbed (if the equipment is grounded at the same terminal).

The other common point for the central control switches, and the shifter is the electronic module box, which is located at the passenger side. The module box (also called the "coffin"), has a lid with bolts that allow you to remove the lid. This is where the K40 relay module, ECM, ASR, TCM and CCM modules reside. Between this box and the firewall, there is a gap, which sometimes get plugged with leaves and debris, and allow water to get into the module box. This water contamination can cause all sorts of strange electrical behavior, especially when it is around freezing temperatures.

I know you checked the water leaks at the firewall, but the problem area is just near firewall side of the coffin.

While you are there, you might as well remove the TCM, and check for ATF contamination :). This also allows you to have a peek at the bottom of the module box.
 
#11 ·
Please forgive the Overly-Simple suggestion, but have you tried Disconnecting the Battery, waiting 30 minutes, and Re-Connecting?

Also, in what condition is the Battery?

I have found these W210s are extremely 'Voltage-Sensitive', and it does not take much to throw them into a Tizzy...

Just a simple/free thing to try...

G
 
#12 ·
Great suggestion, worth trying too. Too bad the OP does not have a scanner that can read the TCM codes. I believe that a bad old style shifter (or a bad connections with the TCM) does not generate a CEL or OBD2 code. The 3 digit internal code would read 114.

The only thing with the transmission problem is that when the key is removed, the TCM power is turned off by the K40 polarity protection relay, so I guess it is equivalent to battery disconnect. As the transmission in hard limp mode (as reported), the fault seem to be persistent (hard fault).

The CCM is however powered even if the key is off, so battery disconnect as suggested will reset the module.
 
#13 ·
Alright then. More hours at work leaves no hours for car repairs but I have moved forward a tad bit.
@fabbrisd1

Received the transmission adapter and attempted installation. The link shows the part I received but... the mounting bolt would not thread and after closer inspection, the mounting bolt in the new adapter is 0.05mm larger than in the old adapter. However, the o-rings on both adapters had the same dimensions so I swapped the new o-rings onto the old adapter and installed.

The harness plug was dripping with ATF so I disconnected battery and used brake clean and compressed air to remove all of the ATF from the plug. There was some ATF on the wiring harness behind the plug but it did not migrate more than 1 inch up the harness (on the outside anyway). Again brake cleaner and compressed air to clean the harness and reconnece plug and battery.

Picture here: https://www.amazon.com/gp/product/B00DOCVVVI/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1http:/?

I did not clean the TCM because I had not performed the "warm up" task previously mentioned. Did the warm up task and brought interior temp up to 75F with air flowing through the console vents to the back seat as recommended. Road test reveals still in hard limp mode.
@mrboca

Battery disconnected during above repair but I had also done this when the problem first arrived. As noted, still in limp mode. Update on center console. I now have ASR switch and trunk release switch power -both features are working. I did have window switch power for a moment but no sooner than I rolled the widows closed again, I lost window switch power in the console. I still have lights on all of the console switches and the shifter.

At the same time, when I reconnected the battery following the above repair, I lost radio power about 3 minutes and then it magically appeared again. While resetting radio features again lost power for about 30 seconds and it magically appeared yet again. Radio power is again steady now.

Seems an awful lot like a loose connection - perhaps the ground you referred to. Would you have more information on how to locate the common ground in the right side/passenger foot well?



I just ran out of time this weekend to go further. The TCM board clean recommended by fabbrisd1 and the ATF/water/debris/relay check recommended by mrboca are next on the list. I will update when I have the results.

Many thanks to all. Keep those tips and hints coming!

R
 
#14 ·
If you take a look at the attached link, you will see what water intrusion can do to the modules in the module box.

http://www.benzworld.org/forums/w210-e-class/2774842-w210-wet-underhood-electronics.html

His is probably a mild case. I had heard people complaining half of their TCMs had submerged in water :(.

Normally between the fender and hood water draining is not a problem. But if you have a blockage allowing water to collect somewhere, it will seep into the module box.
 
#15 ·
Also check out the circuit diagram for the power windows. The CCM provides a common ground reference for the switches (pin 6 on the window switch unit, and pin 77 on the CCM. If there is some corrosion at the CCM connectors, you will have problems with switch recognition. The other area is the ground terminal G203 where the CCM is grounded (left top). G203 is located at the right (passenger) footwell. Pull the carpet at the firewall side. Remove the steel door. Look for the terminal where the brown wires go :). Also check at the CCM side, especially if you have traces of water contamination in the module box.
 

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#17 ·
Alrighty then.... got some time today to start after the ETC module. There is no moisture or condensation anywhere in the box. External examination of the wiring harnesses does not reveal trans fluid nor is there any accumulation in the bottom of the box.

However, I did find a red/green wire shown in the photo floating next the ETC and don't know if it supposed to be connected to anything. I tried to figure this out but it looks like this wire goes everywhere! I found RED/GRN in all of these places but none of them have anything to do with the transmission or windows.

• air pump relay to right adjustable camshaft timing solenoid
• for the fuel pump relay
• activated charcoal
• body acceleration sensor
• all 4 O2 sensors

It also shows up for the purge control vale - could this be the recurring P0442 code? But I did not find RED/GRN in the ECM plug diagram but….

I did find the GRN/RED for the ECT sensor and it does attach to the ECM.

So do I have RED/GRN or GRN/RED? Do I need to fix this?

And so…

I attempted to get the ETC disconnected but can only get the lever part way and I had to use a pry tool to get this far before I ran out of case to gently pry against. I am aware how brittle plastics have become in these aged cars and I don’t need to break yet another part!

How do you get the lever to move beyond the point I am showing in the photo?
 

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#18 ·
Is the arrow pointing to the ETC or the CCM ? The CCM is supposedly the closest one to the firewall. Why remove the ETC ? do you have a problem with the traction control ? For the CCM , I think someone posted recently on how to remove it (slide and lift, or lift and slide the tabs, I do not remember).

The red/green wire is somewhat interesting. Nearly all the circuits you listed would generate some CEL or another if the power to them is removed. I think P0442 is possibly with the fuel cap. You should be able to hear the purge valve tapping when you start the engine (right behind the driver's side headlight, with one hose coming and one going away to the engine with a connector at the top. You can do a continuity checking between this and the open red/green wire in the module box.

I wondered how the red/green wire got loose. I just wondered if it got broke when someone removed a module prior?
 
#19 ·
I can't be sure on that wire - I only get one recurring error code - my dreaded P0442. The continuity test is a great idea and I'll get to it.

I prolly should also do the continuity check between the wire and the ECT sensor in the event this is a GRN/RED wire instead of RED/GRN. Can you point me to the ECT sensor?

About the ETC/ECC/TCM/ABC/XYZ

I wasn't able to find much on where what is located in that electrical box so uses a SWAG for the board cleaning suggested by @fabbrisd1 earlier in this thread. In the original message @fabbrisd1 referred to the board as the TCM. I did not take the original comments from @fabbrisd1 to mean the circuit board in the transmission although I may misunderstand what his instructions are. Somewhere in all the reading on this forum I read that the correct name is the ETC.

I'll be happy to call it what whatever it needs to be so I can find it and check for fluid. Where is it by the way?

Glad to know that the unit I was trying to remove is the CCM and I'll follow your prior instructions just as soon as I figure out how to get that pesky latch open.

Sorry for the confusion of terms - I abundantly appreciative of the patience and help.

More to come.
 
#20 ·
The ETC is the Electronic Traction Control or something like that. The TCM is the module that is for the transmission control. It is also referred to as EGS (Electronic Gear Selection).

The ECT sensor is where the thermostat is. Just follow the top hose from the radiator to the engine. If it were the ECT wire, meaning the ECT is not connected to the ECM, the ECM would read infinity as the ECT resistance (it is just a thermistor) which corresponds to - (minus) XX degrees C which would be flagged as implausible temperature reading with appropriate error code. Besides, when you start and run the engine, if you see the coolant temp gauge moving up, then it is not the broken wire for the ECT.

The other item is the switchover valve for the air pump. If it is not powered then you would get a P0410 code after a drive cycle. You can do the continuity check on the switchove valve cabling too. It is just nearby the secondary air pump. which feeds vacuum to the check valves on either side in the front.
 
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