1990 Mercedes-Benz 420SEL Repair and Maintenance
A guide to problems, costs, maintenance and repair for your 1990 Mercedes-Benz 420SEL
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1990 Mercedes-Benz 420SEL ProblemsBad Switch/Blower Motor Resistor Assembly May Cause Inoperative Heater Blower Motor
Other than a defective motor, a bad switch or blower motor resistor assembly can cause an inoperative heater blower motor.
It is not uncommon for the idle air compensator to get stuck in one position, resulting in the engine idle speed (rpm) being too high or too low. Replacement of the failed compensator may be necessary to correct this concern.
1990 Mercedes-Benz 420SEL QuestionsHow to replace my cabin air filter if I have one ? Thank You (1 answer)
The economy needle has gone from black all the way to red.
as soon as the car run the abs ligth in the dash goes on. in reverse the car don't do that