Hi, my name is***** that the electronics plate was correctly installed and the electrical connector for the plate was also replaced you should first inspect the transmission control unit to be sure that transmission fluid did not find it's way up the wiring harness and into the control unit. If the control unit is dry you will need to get the car connected to the Mercedes tester to have the transmission fault codes erased. After replacing the electronics plate the fault codes in the transmission control unit will need to be erased or the transmission will remain in limp home mode. Other possibilities are a faulty transmission, control unit or selector module but if the electronics plate was replaced because there were fault codes for the speed sensors erasing the fault codes should get it working.
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