rocketboy2000

Hi there, love this site and everyone who participates!

we had a big snow and i pushed my 2010 GLK350 pretty hard to get through it. had dash ABS fail lights afterwards and suspected i may have damaged a wheel speed sensor. decided to give it a bit of time in case there was some ice in there or something and, indeed, the problem went away. did not have a scanner. that was three months ago.

now the engine lights come on and i get ABS and ESP failure dash warning messages. the exclamation triangle comes on as well but will go off if i disable ESP. i do have a BlueDriver scanner now which provides the following:

C2001
NOT PRESENT
The supply voltage of control unit "N30/4 (Electronic Stability Program control
unit)" is too high (overvoltage).

C2000
NOT PRESENT
The supply voltage of control unit "N30/4 (Electronic Stability Program control
unit)" is too low (undervoltage).

C1945
NOT PRESENT
There is an internal fault in component "N30/4 (Electronic Stability Program
control unit)".

C1944
NOT PRESENT
There is an internal fault in component "N30/4 (Electronic Stability Program
control unit)".

C1001
NOT PRESENT
There is an internal fault in component "N30/4 (Electronic Stability Program
control unit)".

P0856
MIL/PRESENT
Traction Control Input Signal

my question is, could this still be a wheel sensor issue? i would rather not have to take each wheel off to check but will get a probe camera if its possible this is the problem and am able to see with such a device.
or, am i looking at a replacement of the N30/4 unit?

any insight appreciated!

Silver Shadow

I have a very similar issue which started a couple of days ago. A bunch of codes and warnings. C1132, C3270, P1425, U140D, U140C, I had about a dozen yesterday. It even went into limp mode a couple of times. I have a C1132 RR sensor code. I have a sensor to install tomorrow to see if it works.
I replaced the battery because it failed a load test but that made no difference. I also cleaned the ABS Module connecters thoroughly which also did not help.

Odd Piggy

That looks like an ESP control unit failure. But before replacing that expensive part, crawl underneath (engine off, in park, parking brake on, wheels chocked) and look for a broken wire on one or more of the wheel speed sensors.

andreigbs

Good advice so far. I would add to check the reluctor ring. When those go bad, you'll get similar errors including limp mode.

Silver Shadow

I replaced the RR ABS sensor, no change.

Odd Piggy

May be the ABS control unit. I hesitate to tell you to change it because chasing phantoms can be frustrating and expensive. I’m not an MB tech. You have a number of codes, some of which may not be related.

Silver Shadow

BTW the ABS and ESP control module is the same part.

Mmr1

With high and low voltage codes be sure it’s getting proper voltage , bad ground happens often . Be sure the battery produces proper power.

Silver Shadow

I fixed mine today. 6 hours with a few headaches. The problem was the ABS tone/reluctor ring. They aren't sold separately anymore for the GLK but I cross referenced the part number and got the right one on Amazon for $20 CAD. Part number is 2303570182.

W205C43PFL

It is always the most simple things, the ones that you least expect that fails causing issues, glad you figured it out, thanks for your update and the part number.