Have Mercedes Questions? Ask a Mechanic for Answers ASAP
My name is ***** ***** I am a professional here at Just Answer. I noticed that your question had not received a response and thought I would see if you still need help with this.I apologize for the delay and I hope I can still assist you with this here.
From what you have described here this sounds like an internal electrical fault with the command itself on the dash.I have seen this fail before in the past needing replaced to correct this type of fault here.What needs to be done is to have the fault codes checked/read out using a scan tool that will plug in and communicate with all computers in your vehicle.Once this has been done any codes set need diagnosed to make sure this is the cause.I suspect it is as I have seen this issue before in the past causing battery drain as well as what you see with the display with the key off.Once it is replaced it has to be coded/programmed with a dealers sds machine in order to operate properly in your model here.
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