1994 Mercedes-Benz S420 Repair and Maintenance

A guide to problems, costs, maintenance and repair for your 1994 Mercedes-Benz S420

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1994 Mercedes-Benz S420 Problems

Transmission Oil Seals May Leak on High Mileage Vehicles

High mileage vehicles may develop a leak from one or more of the transmission oil seals.

Bad 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.

Poor AC Performance Due to Refrigerant Loss

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.

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1994 Mercedes-Benz S420 Reviews

the heater valve blowing warm air out of the vents and air condition works off and on. I was told if I by pass the heater valve Ill have good air condition but no heat until I replace the heater valve. rather have cold then heat right now. And I was told I can rebuild the heater valve, so 1, how do I bypass the heater valve and 2 is there a kit to rebuild the heater valve and where do I buy it?...
My asr light is,on what is the problem and cost
I like this car, it is a 1994 S420, I had it for 6 years the main problem was the transmition, I have to build it twice. It has some electrical and minor michanical problems like any other cars the window motor has to be replaced twice, the heater/AC fan stopped workig for no reason, the sun roof gets stuck sometimes, the seats had some movement problem. Driving is enjoyable, engine is super po...

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