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.
This sounds like a computer has detected a fault with one of the components involved with manual shifting.This can be due to a shifter paddle itself failing or a faulty sensor.What needs to be done is to have the fault codes read out with a fully compatible scan tool that will plug in and can read all computers in your model to see what codes are set.Once this is done there should be at least one code set that will help to locate and repair this issue here.This code will need diagnosed and repaired.If you can get the codes read out and post the code info here this will help.But I have seen in some cases where a paddle can short out or send a false signal disabling the M mode.
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