Are you saying that the mode control doesn't switch the air flow to defrost or bottom vents?
September, 13, 2010 AT 6:06 PM
In defog mode, there is no output. In heater mode, heated air comes out the vent. A/C and vent modes are fine.
September, 13, 2010 AT 6:11 PM
The mode control doors on that car are vacuum operated. First check that all the hoses are hooked up and nothing is jammed. If it's an Auto temp control system. There is a module that controls the vacuum. If it's manual, there is a vacuum rotary switch. Make sure you have a full vacuum supply coming in from the engine on the black hose. Measure the vacuum and compare it with manifold direct vacuum.