ML270cdi 2003 in that abs / bas/esp lights on

[wildrat]

I have issue with ML270cdi 2003 in that abs / bas/esp lights on.

The abs/bas is on all the time and the esp only goes out for 3 seconds when starting engine

Have replaced brake light switch and one wheel sensor that the cdp diagnostic found

Also, test motor runs in ABS unit swapped relays etc.

However, cannot get ABS to respond to the diagnostic at all ?

I am assuming ABS module has gone U/S any guidance ?

Thanks John

 

[mersum1es]

Wiring harness of ABS W163 is prone to fail...

 

[tony jr]

Low battery charge voltage can cause this problem as can the tracking if it has been altered. Take a look at this: http://forums.mercedesclub.org.uk/index.php?threads/2002-ml-270-bas-esp-ecp.130634/


Sent from my iPad using Tapatalk

 

[umblecumbuz]

The harness that comes up underneath the abs unit and ends in a multiplug mating to the socket on the unit, can chafe where it rubs against the inner wheel arch. That's worth checking.

An unusual fault we have also found on my son's ML270 is that the electric motor on the abs unit itself sticks, causing a lot of pretty lights as you've described. We slacked off the motor from its housing, which got it going, and then retightened carefully, stopping the process just before the motor began to stick. So far, problem solved - but a diagnostic readout did not spot this as the cause.

 

[wildrat]

Thanks for the reply’s sorry for delay

Have now changed front left abs sensor as wiring was repaired was flagged in gearbox module fault

Have replaced ABS ECU as have issue that my CDP diagnostic will not communicate with ABS module at all just says dose not respond. (fine on all others)

Have swapped the ABS relay and fuse and looked at the wiring under arch cleaned plugs etc.

Have BAS/ESP ETS ABS never go out EPC comes on with ignition goes out for 2-3 seconds on start then comes back on

Is there any other fuses that power the ABS ECU? had similar issue with E320cdi and was fuse tucked away by Engine ECU

Or would it be best to pay for star diag of issue but not sure if there diag will find issue if module not talking?

Any help appreciated john

 

[umblecumbuz]

There are a number of sensors that can trigger ABS warnings - yaw rate sensor, brake light switch, steering angle sensor, each wheel speed sensor - as well as a fault with the ABS unit itself (which, as you've found out, may not show up as a separate fault on a code reader).

There is a saying among the boating fraternity: A boat is a hole in the water in which you pour money. Don't I know it! That can apply to Mercs, too!

Your conclusion now is the obvious one. Get it on Star. The alternative is to keep throwing money and time at it in hope ...

 

[wildrat]

Sorry should have said brake light switch as well has been replaced.

I understand there are other sensors that will cause errors it is the non-communication that has me confused if I can get module to talk can fix other issues my self

Do not fancy spending £180+ with Merc for diagnostic to be told it won’t talk and needs ££££ to find out more or will STAR find a wiring issue of list the fault without talking to module?

 

[Uncle Benz]

If you have changed the unit and still have no comms it is very likely the unit is not powering up. From memory there are two red wires in the plug with larger pins than the majority in the plug. They are up one end and next to each other usually. Check you have 12v on both. If not you have likely identified the problem. You just need to find the break or fuse.

 

[wildrat]

Thanks for the input m8 but to top it all numpty in white van wrote off car today $%*£ so now academic thanks john