daugherty83

After having nothing but extremely hot heat all winter regardless of what temperature setting I used, and hearing a clicking coming from the passenger side behind the dash when the temp setting was turned up to a hotter number, I recently did the on board diagnostic check that is available if you have the digital heat/ac and came up with codes 21 and 41. The 21 code If I have read correctly can usually be disregarded due to the amount of light that is available when performing the check. The 41 code came up as well though and thanks to a FSM I have came up with trouble areas that cause code 41. This is what the link he posted says for code 41. Anyone have an idea of what this servomotor will cost if thats the problem. OR will I need a whole new ac/heat assembly??

Detection - Air mix control servomotor

Trouble areas -
Air mix control servomotor
Air mix damper position sensor
Harness or connector between air mix damper servomotor
and A/C control assembly
A/C control assembly

Anyone have an idea of what I need to be looking to replace. This is all new to me. Thanks in advance./

tunnelmotor99

Sounds like one of the flow control doors has broken and/or the motor is bad, both of which would cause a clicking noise and no temperature control. I'm not sure but I think you have to remove the evaporator case to change the motor.

sabre

I think I am finding some of these issues myself. I dont notice the clicking sound but my heat tends to go out and blow real cold. I turn the temp knob back and forth a couple times and it usually kicks back in. I noticed today, however, it started blowing cold and my temp gauge was real close to being in the red. Then the heat kicked in and the gauge went back down. Any ideas? TIA

TheDurk

What does your coolant look like? A flush and fill may help. Thermostat is one thing to check. Water pump is another. My fear is your radiator may be at least somewhat plugged and the heater core is on its way there. If the heater core is doing most of the cooling of the engine, then I could see how this could happen. A funky thermostat would be a much better situation so I would go there first. The flush and fill will also tell you something about the condition of the system looking at what comes out and how fast water travels through the radiator.

I think your case is quite different than the OP's. That said, if you have the digital control, running the self-diagnostic routine is worthwhile. No scanner needed (codes read out on the Temp display) Go here:http://www.ncttora.com/fsm/1996/SIL/fsm/repair.html and read the stuff on Diagnostics: Air Conditioning. You might come up with something.