Have Mercedes Questions? Ask a Mechanic for Answers ASAP
Hi, it sounds like there is a fault with the transmission speed sensor or with the electronic gearshift selector module. You will need to get the car connected to a Mercedes diagnostic tester to read out the fault codes that are stored in the transmission control module. The codes in the transmission module will point to the problem. The most common failure are the transmission speed sensors. The speed sensors are part of the transmission conductor plate. A conductor plate replacement is approximately $950. The fluid level in the transmission should be checked to be sure it is at the proper level.
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