Bad Switch/Blower Motor Resistor Assembly May Cause Inoperative Heater Blower Motor on Mercedes-Benz 420SEL

Problem Description and Possible Solution

Other than a defective motor, a bad switch or blower motor resistor assembly can cause an inoperative heater blower motor.

Problem Data
RepairPal Verified
Average mileage: 179,100 (145,000–230,000)
2 model years affected: 1990, 1991
9 people reported this problem
Viewing 1 - 3 of 3 comments
when I place in key and start to turn car on blower will come on sometime when I start the car blower goes off most of the time the blower does not come on at all.
the blower motor was rewplaced 2 years ago and it quit working but i hear noise when i push buttons on air condition compressor is fine no air comes out of the vents