Mercedes-Benz S420 Repair and Maintenance
A guide to problems, costs, maintenance and repair for your Mercedes-Benz S420
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Mercedes-Benz S420 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.
A refrigerant leak may develop from one or more of the following AC components: AC compressor, hose manifold for the compressor, or the evaporator core. The loss of refrigerant can cause poor AC performance. Our technicians tell us that proper leak diagnoses should be performed in order to determine the cause of any refrigerant loss.
Ports in the cylinder head related to the emissions air injection and EGR systems can clog; the cylinder head should be removed and the ports cleaned.
Mercedes-Benz S420 QuestionsWhen I press the gas down my AC decreases. What could it be? (1 answer)
When I apply the gas it decreases everytime.
After sitting overnight it starts right up.