I recently replaced the thermostat on my 2003 Jetta 4 cylinder. The engine temperature is normal at 190F. However, I cannot adjust the inside blower temperature. It is always hot. The fan works and the heat can be directed to defrost, vent and floor.
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2003 Volkswagen Jetta Question: The heater control in my 2003 VW Jetta only blows hot air. Cannot adjust cooler
Answer #1G. T. Service Center (2255 Answers) , Stephenville, TX - (254) 638-3236ProfessorG January 10, 2014, 17:09Master
The temp control is toward the top of the heater box. It can be accessed behind the stereo and heater control head. These parts are plastic with a cable control. You might remove the stereo and control head, and while turning heat control, see if it is moving properly.