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.
The first thing that needs done here is to have the fault codes checked/read out using a scan tool/computer that can plug in and communicate with all computers,mainly the heater/ac computer/panel itself.Most likely one or more codes will be set that will aid in diagnosing and locating the fault here.
There are a couple of bulletins on the heating and ac system on this model here,both require programming of the heater/ac control unit with updated software and actuator calibration to be done using a dealers SDS machine.If no codes are set the software update needs done as well as actuator calibration.This is usually an hours time to have this done and needs done by a dealer or repair facility with an SDS machine.This takes about an hours time for them to do.
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The SDS can be used to calibrate and you can do this yourself if you had this tool or one like it but the programming unfortunately has to be done by a dealer or authorized repair center as the SDS machine connects online to Mercedes to do the programming and only a dealer or authorized repair center can do this part.
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