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Please help with ABS/ASR error codes

64K views 39 replies 4 participants last post by  salman108 
#1 · (Edited)
Hi Guys,

I ran the scans on the merc, and following were the error codes

C1000----------ESP/SPS/Traction control module (N47-5)
C1012----------Battery voltage too high, circuit 87

C1010----------Battery voltage too low, circuit 87
C1022----------CAN communication with engine control module (right)(ME-SFI, N3/12), interrupted

C1501----------SPS P-valve (Y10)


Upon clearing the codes and running the scan again, the other disappeared, but C1501 remained.

Can some one please guide me, as to what seems to be the problem.

UPDATE:
Now 1501 is gone problem's been fixed.
C1000 is the only code left on BAS system.


Thanks for your time and attention.
Regards;
 
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#3 ·
Update:

I read the actual values from the BAS module and they look like so

01 Diaphragm travel ------------ 3.75cm and when press the pedal 15.32
02 Stop lamp switch ------------ OFF and when press pedal is ON
03 Release switch NO contact ---- Stays OFF, even if the pedal is pressed
04 Release switch NC contact ---- Stays ON, pedal pressed or not.

Can some one please help me understand what above values ( 03 and 04 ) point out to ?
The general error code is C100 - Current in the BAS module.

Best regards
 
#5 · (Edited)
The ABS / ASR light does not come on.
The ABS seems to work, and I feel it pumping while braking.
The traction control seems to be doing it's job and doesn't let the wheels spin.
The codes were pulled by official dealer, not sure what he used ...

the only symptoms are the front brakes are doing all the work while the rear brakes are getting lazy :(
Out of the front the front right seems to do thrice as much.

any help please ?
 
#6 ·
You haven't mentioned the miles on the car. However, I would change all of the flexible lines at the wheels. Sounds like one or more of them is collapsing internally. The lines are less than $20 ea. at several online sources. Dealers use StarTech diag systems as do very well equipped indy shops.

Good Luck,

Jayare
 
#7 ·
The car has done 138,000 km but you can take that twice of anywhere else in the world (276,000).
We drive in the toughest conditions on the planet :(

As a precaution, I did open the plugs, drained and refreshed brake oil in all 4 wheels. This showed no improvement :(

I will try to find a star-tech system and have a scan done on it.

the C1000 is the only code left on the car's chassis section and I am most scared of it since it is with the BAS system.
 
#8 · (Edited)
**********
UPDATE
**********

Finally got a chance to work on the merc.
Working from down to up.

1. Cleaned the rotors.
2. Cleaned the speed sensors ( the cogs on the rotors were dirty)
3. Checked the values from speed sensors, by turning the wheels. All values are OK.
4. Replaced the BAS module (found underneath the Brake booster). As a result C1000 is gone.

Now no other codes found on any thing, except C1025 CAN Communication BAS communication with ESP control unit

I removed this code, and restarted the car, and the code reappeared as C1025 Stored.

As per the startek's diagnostics
There are NO warning lights on ESP, or the yellow triangular light.
There are NO warning lights on ASR.
According to startek no further work needs to be done, and 1025 should be ignored !

Can some please help me, how to remove C1025.

The only problem I face is when I apply the brakes hard, there is a grinding noise coming from the front wheels (and paddle pulsation which is ok).
The brake pads and rotor discs are brand new.

Any help highly appreciated.
Thanks and regards
 
#15 ·
4. Replaced the BAS module (found underneath the Brake booster). As a result C1000 is gone.
When you did this, are you sure that it was correctly installed?
There are different version of this module, and each must be version coded
by a STAR computer for different engines/chassis...

Also,
Can you please list the part number of that BAS module, since there
is an remark about C1025 error code in relation to part number;
025 545 47 32
025 545 48 32

br,
syljua
 
#9 ·
Hi Guys,

Today i got the codes scanned from the Merc Dealer, and for sure he was using a star diagnostic machine.

Following are the results

BAS
C1025 - CAN signals ABS not available.

KI
B1041 - CAN communication fault to traction system control module.

LWR
B1260 - Sensor fault Axle sensor front A52

I don't know what LWR and BI are, and i can't seem to find the codes on the net :(.

I don't know how to fix the C1025 :(, any suggestions please ..
 
#10 ·
KI
B1041 - CAN communication fault to traction system control module.

LWR
B1260 - Sensor fault Axle sensor front A52
I'm quite sure that KI is Instrument Cluster (Kombi Instrument), while LWR is the system for automatically raise/lower the adjustment of the Xenon headlights.

The LWR seem like a separate problem. Maybe you can have a look at the computer lines diagrams for the other two;
http://www.autolib.diakom.ru/CAR/Mercedes-Benz/1997/S500/SYSTEM WIRING DIAGRAMS/6414.pdf

br,
syljua
 
#12 · (Edited)
Ok, now I am desperate ....

I hit a dumpster and now have to pay up for fixing the hood and cracked bumper :( ...

My problem as stated before is just one fault code C1025 CAN signals ABS not available.

and the symptoms are:

1. the car is not stopping as well at all.
2. The ABS is triggered at all speeds; at 20mph there is no chance the wheels would
lock on a dry road yet if i clamp on the brakes hard, ABS kicks in.

as a result of this strange ABS behavior , the car skids too much instead of avoiding it.
Strangely the above behavior improves at higher speed ( 100mph and above ). So may be some thing wrong with vacuum ?

I am at the edge with this thing, and going to start replacing brake parts one by one. ( brake master cylinder first, ABS second )
Any information would be very welcome.

Please help.

Best regards
 
#13 ·
Ok, now I am desperate ....

I hit a dumpster and now have to pay up for fixing the hood and cracked bumper :( ...

My problem as stated before is just one fault code C1025 CAN signals ABS not available.

and the symptoms are:

1. the car is not stopping as well at all.
2. The ABS is triggered at all speeds; at 20mph there is no chance the wheels would
lock on a dry road yet if i clamp on the brakes hard, ABS kicks in.

as a result of this strange ABS behavior , the car skids too much instead of avoiding it.
Strangely the above behavior improves at higher speed ( 100mph and above ). So may be some thing wrong with vacuum ?

I am at the edge with this thing, and going to start replacing brake parts one by one. ( brake master cylinder first, ABS second )
Any information would be very welcome.
Ok, your car is telling you, that the ESP module has no communication with the
BAS unit. If you look at the diagram I linked, you'll see that both CAN High (H)+ and
CAN Low (L)- are shared wires for all modules (140 series have only one CAN bus,
while newer cars have several).

No, the BAS is not pictured in that diagram (because its only on 98 models, I think).

(Nevertheless, you also had a fault code where the instrument cluster also did not
communicate with your ESP. Blinking of the triangle in the cluster would be
typical things that would be communicated thru that connection.)

Now, what I would suggest, with battery disconnected,
is to remove both the BAS, and the ESP control module.
Find the Green/White (CAN H) and the Green (CAN L) wire on each of the wire
connectors, and measure if you have connection between BAS CAN H to ESP CAN H,
and BAS CAN L to BAS CAN L. Do also measure that none of them
are shorted to ground.

The effect that this is not present in higher speed, is just that the traction
is not functioning at speeds above some limit (don't remember which).

Apparently, some of the modules are indeed getting the wheel rotation
signal, or else you would not have the speedo working.

I would advise not to start swapping out lower order mechanical components, before you
solve the data communication issue.

Most likely, the fault is in the BAS end, since your car seems happy with the
communication between the ESP and the KI (Instrument Cluster).

I think that the ESP is perhaps the only unit in the CAN network that expect some
communication with BAS. The rest of the data modules does not care...

br,
syljua
 
#14 ·
Thanks boss,

some more data which I should have mentioned before

1. No warning / error lights on the instrument cluster
2. ASR works fine and never lets the wheels spin
3. All speed sensors work fine, I have checked them independently.

I will carry out the steps you mentioned and update this thread.
 
#16 ·
1. No warning / error lights on the instrument cluster
Ok, I realize that you have BAS with ARS (not ESP? (where you would not have
a separate BAS module, but integrated into the ESP)).

Yes, for the instrument cluster to receive warning lights from BAS, the
BAS must be able to tell the instrument cluster via the CAN bus...

br,
syljua
 
#18 ·
Hmmm,

I checked the green / green / white wires , they are good.
I replaced the BAS and Traction control unit form a known good car, the problem still persists.

My friend pointed out to some thing that needs to be changed behind wheel bearings.
Is there any thing there related to traction control ?

Thanks for the time and help.
 
#19 ·
Code 1025 is a BAS problem and a well known fault where the stop lamp switch is at fault. It can kill the speed signal within the BAS ECU and a CAN fault.

all the cars including the 129,210,202 and 203 get this fault, dead easy to change the switch on top of the pedal and cheap to buy.

The ESP cannot run when there is no active BAS
 
#20 ·
Hi Television, thanks for answering.

The brake switch has been replaced already, C1025 will not go.

ESP works fine I checked the following way:
Loaded the car on the jack, started the engine.
Now with all wheels stationary I turned one wheel at a time, the ESP light comes on.
This means all wheel speed sensors are operational and ESP reads them.

Second Take the car on road with loose gravel on it, and intentionally try to slip the car, the traction control kicks in and corrects the car. When I try to give it too much gas starting from zero speed the traction control kicks in and stops the wheels from spinning.

Any more ideas guys ...
 
#21 ·
In its full description 1025 is a CAN fault where the signal is not made or corrupted.

There is one big problem on all MB connectors where the CAN signal exist. CAN signals draw no current at all. With signals that have current flowing the connectors can arc themselves good, signal connectors cannot do this. A good example of this is with the seat connectors that are poor on the 202,208, 210 and the SRS lamp comes on, or take the gearbox ECU where the car locks up in say second gear during years 1998-1999.

I would first get some non drying switch cleaner from Radio Shack or what ever it is over there and spray the connectors on all of the ECU's in question.
 
#25 ·
Indeed you do have a BAS ECU the main failures on this and fairly common is the BAS travel sensor, though this should bring up a different fault code, it certainly does on later cars. Both the BAS and ESP use the ABS to operate through, as it is the ABC ECU that is capable of braking wheels individually.

That circuit the 2 of 2 one does show the ABS pump on the right,they call it something else,,it is the only one with a pump in it.

I will do some more research on this
 
#26 ·
I think the headline needs to be verified, it says ABS/BAS and ESP.

Now the ESP and BAS cannot operate if the ABS lamp is on, and it is the ABS that needs to be fixed for the other two cannot work without the ABS being all good.

So is the ABS lamp on
 
#28 ·
As an alternate solution, is it possible to change the BAS + ASR to the newer ESP with built in BAS ?

would it require me to change the brake master cylinder + Booster or just swap cards
with the new one and re-wire ?

best regards
 
#30 · (Edited)
Hi guys,

I got hold of the mercedes maintenance manual, a multimeter and some other tools.

I am on this page , and it is asking me to check resistence and some times volatage between some connections







In this table, I can't figure out the connections ... where are they located and which pins to use !!!

I have circled and pointed to with thick black lines.

For example where to find 1.4 and 3.2 as mentioned in the last row of the table.
Please help,

Best regards
 
#31 · (Edited)
OK, to keep a log of my beast.
Today I finished testing the mercedes way as listed in the attached PDF.
All tests are 100% perfect.

Thus I am beginning to suspect that either
1. The diaphragm in the brake booster has an issue
2. The travel sensor is giving an out of bound value, thus causing CAN shutdown in BAS. ( this kind of explains C1025).
3. The solenoid in the brake cylinder is shot (this explains my initial information that front brakes do all the work and rear are just lazy).

On saturday we plan to replace the brake master cylinder with another one.
Any other ideas camp ?

Thanks & Best Regards.

PS: can some one please help me with Parameterizing BAS control module, model 140. I don't have that tool listed in the PDF. Anyway other way it can be done ??
 

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#33 ·
PS: can some one please help me with Parameterizing BAS control module, model 140. I don't have that tool listed in the PDF. Anyway other way it can be done ??
Ok, with the replacement of the BAS module, you cleared all error, and that
the only related error that stayed, C1025, is the one thats warned in the document
can pop up when reading the other modules error codes (like, well I (BAS) cannot
get signal from the rest, ASR etc. because they are busy doing diagnostics.), that
can then be just neglected.

No other codes for BAS turn up, and the car seems to operate good in taking-off mode (ASR).

Its also working good in braking, just that the ABS seems to kick in too early.

My theory; Your replacement BAS module, thinks it controlling a smaller car (all
of the others in the parametrization list are smaller). It thinks your panicking much
sooner than you really are, and gives you higher pressure too soon.

I would take it to the dealer, or someone with HHT/Star Computer, and get
that parametrization correct. Its there for some reason, I guess:)

I would do this first, as the new unit does not complain about any of the
sensors/workings of the brake booster. (which you have measured and found
fine/ok yourself)

br,
syljua
 
#32 ·
You can do it with STAR and possibly some other scanners, on all the faults with the 1025 code it has always been the travel sensor in the post in the UK, but also the master cylinder has to be correct
 
#34 ·
Thank you syljua and Television.

I will try to get an estimate from the dealer ( costs about 2 salaries ! ) ... arghhh

in the meantime I will try to think about this Mercedes tool. looks like easy access vero board .. I will study more and update this
 
#35 ·
UPDATE:

Changed the master vacuum cylinder from a known good car ... no improvement.

So back to drawing board,

Now the plan is to one by one follow and check all 4 wheel speed sensor wiring, going to the ASR unit. and then check ASR's output BAS.

I opened up the right foot well to check the state there. I saw a disconnected connector attached here in the post, can some one please point out what it maybe for ?

Thanks and best regards
 

Attachments

#37 ·
Syljua,

I got my hands on the star machine ;) .. this workshop guy is nice !

and as you pointed out yes there is a problem with setting BAS parameters.
The variable quoted in the BAS is 6, where as it should be 8 as per the manual.
However there was no option to change that variable ...
any pointers on achieving that please ?

Best regards
 
#39 · (Edited)
ok inching close to the solution

Here's what I learned from the manual, which coincides with what you wrote.

Preliminary testing

1. Review section 0 entirely before connecting the HHT.


DTC readout is not possible using an impulse counter scan tool.

2. Connect the HHT to the data link connector (X11/4) according to the connection diagram (refer to section 0).


Test cables are not to be hooked up to the HHT while performing component activations.


Read out DTC memory from ABS, ASR OR ETS control modules before starting repair procedures. DTC memory must also be read out from ME-SFI and EA control modules on vehicles with ASR.
The HHT will indicate the defective components in the display or will refer to the proper test step in the diagnostic manual.

Version Coding of control modules
When swapping ETS control modules, the ETS control module must be version coded using the HHT. Follow the directions as indicated in the display of the HHT. By using the test button "?" on the HHT, the version code of the control module will be displayed.

3. Additionally review: 21, 22, 23(connector connections).4. Review the following ETM diagrams:
PE00.19-P-1100B
PE42.00-P-1100B
PE00.19-P-1100D
PE42.00-P-1100D
PE00.19-P-1100A
PE42.00-P-1100A

5. Ignition: ON
6. Read out DTC memory.
7. Read out nominal/actual value displays.
8. Perform component activations.
9. Perform repairs according to DTC memory readout.
10. After completing repairs erase DTC memory.


The Electrical Test Program, see 23, pertains to the ABS, ETS, ASR and SPS systems.
In order to prevent the listing of all the control modules used in the various systems, for each test step, the following is used:

N47 = Control modules for Traction systems

A7/3 = Hydraulic unit for Traction systems
Trying to find the referenced diagrams, !
I don't know why they didn't put a hyperlink there to the diagrams, and they expect the user to scroll through pages ..
 
#40 ·
Ok, found the problem. On the N47/5 I am getting an open circuit for both the rear wheel speed sensors.

I looked beneath the rear seat and the connector there is fine. Thus the open connection is between N47/5 and the speed sensor connector beneath the rear seat.

Can some one please share a diagram, or some instructions on what to look for ?

I am particularly interested in X35/59 ( Compact harness/taillamp harness separation point), where is it located ?

Best Regards
 
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