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TheSpeedy

Electrical fault in 2011 Mercedes C Class: sat nav failure and warning light illuminated

General electric malfunction

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Navigationssystem is not working

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Warning light in the speedometer of the vehicle

Hey guys, I'm investigating a problem with my 2011 Mercedes C Class petrol car. I'm struggling with a general electrical fault, the sat nav has stopped working and the warning light in the speedo is illuminated. Could this have something to do with the communication between the control units being faulty? Have any of you had experience of this and perhaps even a solution? I would be very interested to hear how you have had such problems rectified in the workshop. Thanks in advance for your help!

(Translated from German)

20 comment(s)


JBeck87

Hey, I had a similar problem with my 2009 Mercedes E Class diesel. I'm not exactly a car expert, but I do have a bit of an idea. At my garage, they identified the control unit as the cause because it was sending faulty signals to the BUS system. The solution wasn't exactly cheap, I had to fork out 10 euros to change the control unit. Have you ever read out the fault memory? That may help to find the cause of the problem. Which error codes are displayed? Please give me more information about your car so that I can perhaps help you more precisely. Greetings

(Translated from German)

TheSpeedy (Author)

Hey, thanks for your quick reply! So my mileage is 149098 and the last service was carried out. Unfortunately I haven't had the chance to read the fault memory, but the suggestion is good, I'll definitely try that. As soon as I have the error codes, I'll get back to you. Thanks for the tip about the control unit, although it sounds really expensive... Maybe someone else knows a cheaper solution? Greetings back!

(Translated from German)

Best Answer

JBeck87

Hey, no problem, always happy to help! Yes, 149,098 kilometers is quite a lot, so problems like this can sometimes occur. In any case, it's worth reading out the fault memory to find out exactly what's going on. As far as servicing is concerned, has everything that was due been done, i.e. spark plugs, air filter etc. replaced? That can sometimes make a difference. Unfortunately, I can't tell you much about a cheaper solution... I asked my garage for a cheaper option at the time and they said that unfortunately the only solution was to change the control unit. But maybe someone else has an idea or it's worth asking another garage. In any case, good luck and let me know when you have the error codes! Greetings

(Translated from German)

TheSpeedy (Author)

Hello, thanks again for the helpful information. Yes, the last service was carried out in full, including replacing the spark plugs and air filter. For now, I will concentrate on reading the fault memory and hopefully that will bring more clarity. Sure, the garage is often the only solution, I just want to avoid it as it's often quite expensive... But well, who knows. I'll get back to you with the error codes. Thanks again and best regards!

(Translated from German)

Femi_

U012087 communication with the starter or alternator has a malfunction. I got this error on my cla250 2013 benz. Can someone help with what yhis issue is?

CarlyMechanic

@Femi_

U012087 communication with the starter or alternator has a malfunction. I got this error on my cla250 2013 benz. Can someone help with what yhis issue is?

The error code U012087 indicates a communication issue with the starter or alternator. This could be due to a faulty alternator, starter, wiring issue, or even a problem with the battery. Start by checking the battery's health and the connections to the starter and alternator. If everything seems fine, it's best to have a professional mechanic inspect the wiring and the control units for any faults. This is a critical issue as it can affect the starting and charging system of your car.

Magand24

Hi, my air conditioning is no longer working. Error code 919100. The refrigerant level is OK and there is no leak in the condenser. The A/C light flashes when activated, but then goes out again, so the compressor does not start and does not cool. What is strange is that it works from time to time after driving on the highway for a long time. I suspect the pressure sensor. Does anyone have any ideas?

(Translated from German)

Magand24

@CarlyAdminBenny

Hello Magand, what kind of vehicle are you driving exactly? Kind regards

Hello, sorry, I drive a Mercedes GLK, 220cdi 4matic from 2013.

(Translated from German)

CarlyAdminBenny

@Magand24

Hello, sorry, I drive a Mercedes GLK, 220cdi 4matic from 2013.

Hello, That does sound like a very strange problem. Has the clutch of the air conditioning compressor ever been checked to see if it is engaged when the air conditioning is switched on? It also sounds to me as if the pressure sensor could be responsible for the problem.

(Translated from German)

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