W163 ML270 BAS ESP, ETS & ABS Lights, C1100 Fault

[91dm]

Hello,

Hopefully someone might be able to help me on this.

My ML developed a fault last week, BAS ESP, ETS and ABS lights came on followed shortly by the EPC light.

It's an 04 ML270, 170k miles. New battery few months ago, no other faults before this.

After a quick search on the internet, I read lots about the brake light switch and K25 relay. After a quick look under the pedal and bonnet, mine doesn't have a switch or relay.

I then plugged in the computer, faults read as below:

C1210 Drive test: N49 (steering angle sensor)
C1178
C1035
C1174
C1181

I cleared these faults and read again:

C1100 Left front wheel speed sensor, open circuit. loose contact plausibility.

Read again and same fault came back.

After another google search, many people said that after replacing the sensor, the fault still remained. The actual fault was caused by worn brushes in the ABS motor.

Is there a simple way on manually turning the pump on to check?

Any help appreciated.

Thanks

 

[Jane270ML]

Early W163's had brake light switch located under brake pedal, on later models they were located under & in the brake servo master cylinder. Mine is.

Check the cable harness running to the ABS connector, on the ABS pump, where it passes a lip on the bodywork. Many reports of harness being rubbed through at this point creating damage and shorting out the cables,
Repair worn-thru cables & wrap some pipe lagging insulation round the harness.
It's accessible via N/S wheel arch.

This may help... http://www.mercedesmedic.com/abspumprepair/

 

[91dm]

Just to update this:

>Changed the ABS pump bushes, old ones where worn but the new bushes didn't make any difference.

ABS lights come on and off randomly, can stay off for a week and then back on.

>Tried a new ABS sensor on the front left which hasn't help. With the old sensor I was getting a live speed reading, with the new sensor it is displaying 0 on the live readings?

Could the new sensor be faulty? I'm thinking of putting the old sensor back in to see if the readings return?

Thanks

 

[91dm]

Can anyone help shed any light on this.

I put two pins into the ABS sensor connectors on the car side to take readings, the drivers side gave a steady ready and the passengers (which registered a fault) kept fluctuating.

Is there an ABS ecu that I could check the wiring/connector?

Thanks

 

[91dm]

Well almost two years later I thought I'd update this incase it helps anyone else.

I had the usual BAS ABS lights on the dash with a fault code for the front left sensor although the speed readings for the sensor were correct.

DTCs
C1210 +30 Voltage
C1174 Steering angle not initialized
C1100 Left front speed sensor, line monitoring
P0500 Vehicle speed signal

After a lot of head scratching and searching, I found a broken wire at the ABS pump connector! After soldering in a new piece of wire and erasing all the fault codes, all lights are off and low range back working again!

 

[91dm]

After cutting back the covers.

 

[Bellow]

I have the same problem ie a range of lights on the dash that are staying on. Trying to sort out a scanner to read codes for pointers and when that's achieved, I'm expecting to be looking at a failed component - or its associated wiring (ABS unit a possibility).

After a lot of head scratching and searching, I found a broken wire at the ABS pump connector! After soldering in a new piece of wire and erasing all the fault codes, all lights are off and low range back working again!

What then, flags up that it is a wiring fault as opposed to component fault?
Out of interest, your broken wire - chaffed through against car or has a mouse been at it (a possibility for my (not ML) car!)?

 

[91dm]

The fault codes on mine suggested left front wheel sensor was faulty however the live speed readings where fine. This made me look at the wiring plus it is easy to access.

Rubbing against chassis and arch liner I think?

 

[paulm2727]

Hi All,

I have ML 270cdi 2004 51K from new. Now when i start the ignition it fires straight away but all the yellow lights start to flash , headlights flash and cant select gears. it seems its going into a lock down, even the rear window kept going down without doing anything? By pressing on the footbrake a few times can engage gear and drive. During driving ESP/BAS light is permanantely on. Any ideas

 

[91dm]

Have you checked the battery leads, earths?