1991 Mercedes Benz 300se Repair Question
Mercedes Benz 300se Heater Problem
1991 Mercedes Benz 300se 6 cyl Two Wheel Drive Automatic 120,00 miles
My heater is working erratically. It will defrost the windshield. but the cabin temperature does not reach the temperature that I set it at. The blower is fine but all I get is cool air blowing.
Sounds like you may have a faulty heater exchange valve. When these fail coolant is restricted into the heater case producting merely cool air out of you a/c vents. The heater exchange valve is located on the firewall. Follow the heater hoses to the metal exchange block on the firewall.
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