Suggestions for those with climate control probs... (no heat)
I recently fixed a problem I had where I wasn't getting any heat from my 91 Legend L and I thought I should share my findings.
* No matter what position the Heat/Cold knob was in, I was only getting lukewarm air.
* The car was running just fine (not a BHG), the radiator was full, and all other buttons on the manual climate control panel worked.
* Turning the hot/cold knob did NOT move the heater control valve near the back of the engine bay.
Attempted Fix 1:
* I replaced the climate control panel with a used part I purchased for $15 on eBay.
Result of Fix 1:
* Problem was still there.
Attempted Fix 2:
* I took out my glovebox and found the air mix control motor mounted on the bottom of the heater core.
* Turning the knob on the climate control did NOT make the air mix control motor or the heater control valve move.
* After removing the air mix control motor, I moved the valve tabs the motor was supposed to shift and found that a) the air got hotter and b) the heater control valve moved.
* I also tested the aix mix control motor by a) measuring the resistance and b) applying power to the pins as directed in the service manual.
* The motor worked so I re-attached the AMC motor and the motor moved as expected. I reinstalled it by turning the climate control knob to full HOT, hooking it up to the AMC motor so that the motor moved into the full hot position, and moving the various levers around so that the motor was re-attached.
Result of Fix 2:
* Success! Hot air and cold air on demand.
* If you have recently replaced your cabin air filter and your heat no longer works, check the connector that connects the climate control panel to the air mix control motor. These connectors are mounted on the bracket that you remove to get to the cabin air filter.
* While the climate control panel MIGHT have been the culprit, the most likely cause for my hot/cold mix to stop working was a loose air mix control motor connector.
2002 Audi S4
1994 Acura Legend L (commuter)
Last edited by S4gunn; 01-17-06 at 06:51 PM.