jimjones26

Hello all. I have a 2011 GLK-350. A few weeks ago I started getting an ABS related error on startup that would go away if I let the car warmup and then restarted it. Now I have the BRAKE, EBD, and ABS Inoperative Error. Bought a scanner and ran diagnostics on the ESP program and got the following codes:

VIN---WDCGG5GBXBF659549
Vehicle---204.956 - GLK 350
Chassis---204
Model---956
Power---Gasoline
================================================== ======================
BENZ_EN_TEST_00002>VIN Identify>Control Unit>ESP - Electronic Stability program(N30-4)>
Read Fault Code:
Total Number : 10
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
6000 1/10
State: Historic
The Supply Voltage Of Control Unit N30/4 (Electronic Stability Program Control Unit) Is Too Low
(Undervoltage).
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
7230 2/10
State: Historic
No CAN Message Was Received From Control Unit A1 (Instrument Cluster).
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
6110 3/10
State: Historic
No CAN Message Was Received From Control Unit A1 (Instrument Cluster).
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
6102 4/10
State: Historic
No CAN Message Was Received From Control Unit N80 (Steering Column Tube Module Control
Unit).
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
7250 5/10
State: Historic
No CAN Message Was Received From Control Unit N80 (Steering Column Tube Module Control
Unit).
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
7266 6/10
State: Historic
Consequential Fault
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
7208 7/10
State: Historic
One Or More Signals Sent From Control Unit Combustion Engine Via The CAN Bus Is
Implausible.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
6264 8/10
State: Historic
One Or More Signals Sent From Control Unit Combustion Engine Via The CAN Bus Is
Implausible.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
5865 9/10
State: Historic
There Is An Internal Fault In Component A7/3 (Traction System Hydraulic Unit).
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
5001 10/10
State: Historic
There Is An Internal Fault In Component N30/4 (Electronic Stability Program Control Unit)

I did test the wheel speed sensors and they all appear fine. I am guessing I have to replace the ABS / EBS control module but wanted to check here first. That's not a cheap part!

habbyguy

It sounds like the same problem I've been seeing (as have a lot of others). The odd thing about this particular problem is that it tends to be intermittent, normally sticking around for a number of days or weeks, then just disappearing without a trace.

In my case, the original problem cropped up but disappeared before the replacement part I bought on a chance (turned out being wrong) was delivered. Then a year longer it came back. Halfway through a road trip, it went away again and hasn't recurred (yet, but I'll bet it will).

The research I've done suggests that the same symptom can be caused by a number of different root causes, including a bad wheel speed sensor (sounds like you don't have that issue), bad brake switch, or a bad ABS computer (the one that's sandwiched to your ABS pump / manifold). There's a rumor that there's an ESP module under the passenger's front seat (IIRC), and that could cause it as well.

To replace the ABS module, you'd have to code the module to your car. I did get a bidirectional scanner that would do that, but I'm not likely to try that unless the problem comes back. The other thing I'd suggest is that most of the failures like this with the ABS computer are from bad (cracked) solder joints on the circuit board. I've read reports from folks who removed the computer, split the case, scraped off the conformal coating, and then resoldering the suspect connections. The down side to this approach is that you really need to have a second car around to drive if this process goes south.

I had some temporary success by removing, cleaning and reinstalling the ABS computer plug, and some have apparently fixed the problem this way.

I also was able to "spoof" the system into working (so my cruise control would work) by accelerating to over 20-25mph, then shifting to neutral, turning the engine off, then turning the ignition back on / off / on a couple times. The error would usually clear and stay off until after I turned the ignition off again. This got me across the country with a working cruise control, and no "Christmas tree dashboard".

At any rate, keep us all posted on your progress - it's a common issue, and the more we learn about it, the better!

FWIW, here's my second (of two) videos on this problem:

Mmr1

The electronic stability control unit says “Low Voltage “ on the code. Low voltage messes up things. How old and good is battery ? . My alternator regulator went bad at 75000m a new regulator was an easy fix. A weak battery can cause codes to show up mainly at startup when load is high, voltage drops to low . Is battery charged now?

jimjones26

The first thing I did was take the battery in and have it tested / charged. The battery is good, alternator tested good. I'm not sure what the alternator regulator is, I will do some research on that and check it. Thanks!

jimjones26

Thanks! I watched your video a few days ago before my code reader came in. The only thing I am worried about is all of the codes that are thrown, but maybe its a fuse / relay / battery regulator issue.

Mmr1

You need to do tests in the car, you took the battery in “they charged it”. So it was low ? It should not be “low “ if your charging system is working correctly. Do you have a volt meter ? Read the battery now and have someone crank the motor to start it while you monitor voltage , see how low it drops when cranking it. With older cars get your own test equipment.

Mmr1

If you drove it today it’s probably charged up now, best it redo tests in the morning after sitting all night . I recently had a low battery for weeks , I found I had a dash camera lock on 24/7, many things can go bad and draw power. Your code said “Low Voltage “ start there .

jimjones26

OK, tomorrow morning I will take a video of the multi-meter reading from the battery cold, through the start, and idling for 10 or 15 seconds.

KanataSteve

Use the secret engineering menu to monitor the voltage. I believe you can also monitor the charging current. Don't make any changes in the secret menu. That could be very bad.

There are a couple of ways to get into the menu, so search here (and on G**gle - mercedes secret Engineering menu) to find the right method for your car.

Here's some info to find parasitic current draw...
https://automotivetechinfo.com/2023/07/quiescent-current-draw-diagnosis/

When searching for instructions on how to use the Engineering menu, you'll find instructions similar to...

"
MB Engineering menu

Turn on to first position
On the radio unit...
Press "end call"
Press "1"
Press "#"
Hold for about 5 seconds
"

... here's a similar set of instructions...

"
MB secret menu

In a separate thread started by Cardonman it was revealed that a "secret Menu"can be accessed. This is intended for service techs, and could lead to putting the vehicle into an unknown state, please be careful if you venture here!

To access the Secret Menu, follow these steps:
(1) Remove the silver Start - Stop button (if fitted) by gently pulling it out
(2) Insert the ignition key
(3) Turn the key clockwise to the first stop (at least one indicator light will come on, but the RH gauge will still point to 'OFF')
(4) Select the Odometer readout in the dash, if necessary, by pressing the Up or Down arrow buttons on the LH keypad of the steering wheel.
(5) Press and hold the “telephone answer” button on the RH keypad of the steering wheel.
(6) Press and hold the “OK” button on the LH keypad of the steering wheel.
(7) Wait about two seconds. The readout on the dash will show the Secret Menu.
(8) Navigate as desired using the Up or Down arrow buttons on the LH keypad of the steering wheel
(9) To exit use the back button (above the LH keypad of the steering wheel)
"

Use the round knob (if you have one) on the centre console to go up and down in the menu and to click and obtain sub menus, and also the "back" button to navigate out of a menu with. Need to move to the bottom of the first page and use the knob to move down to the next page.

Go through the menu and sub menus to find the area that displays voltage and the charge current (displayed while running).


Others have provided much valuable info in this forum on acceptable voltage and current values, along with the ability of stores to "check" a battery (the stores are incorrect many times), others have described acceptable battery types to purchase.

- Inserting my auxilliary rambling here...
Note that if you have an auxilliary battery, it's a great idea to replace it if you change the main battery. It's very simple to do. Best to get one that connects to the existing battery vent tube (if you have one of these batteries). Never take a chance with battery gas pooling in your car. Some feel that the safety bubble on the battery is good enuff (and not use the vent tube). I reflect on seeing batteries of this type failing dramatically in well Engineered battery backup systems. We would have to discard the batteries and their backup system every time. I prefer not to be in the minority of cases of having a battery without a vent tube that fails and bursts the safety bubble venting gases outside the battery. Just my opinion. Never want to be in that situation.

trigital

I would delete all Faults, start engine and after the Fault will be present in Instrument Cluster I will make the diagnosis without stopping the engine.

If any of the Faults code will change from "history" to "Actual" then those should be investigated.

If this one will came again:

5001 10/10
State: Historic
There Is An Internal Fault In Component N30/4 (Electronic Stability Program Control Unit)

a new ESP ( or used,) will be needed.

Anyway, search for water behind the driver carpet where the CAN distribution is usually placed.