q45 air vent control problem

[mcgahey]

My climate system is stuck blowing air from the front (AC) vents. When I select defrost or floor vent, air continues to flow from the front vents. It does this in heater and AC modes. As far as I know the system has never been cleaned nor has the cabin air filter been replaced. This 1999 Q45 has 191K. This was fine for the summer, but I will be need defrost soon.

Thanks

[elwesso]

Welcome to NICO!

Go here, and start on page HA-29

http://www.nicoclub.com/FSM/Q45/1999_Q4 ... Q45/ha.pdf

The "30" mode will test all the mix doors and whatnot, which is where your problem lies. Either the blend doors are messed up, or they're not being told to move properly. In the "40s" section, you can see what the position of the doors should be in.

Report back what you find, and let us know if you need any help along the way!!

[mcgahey]

Thanks for posting the test document.

The "30" mode test showed 32-33-34-35-36 pattern. Does this mean that the door mode motor needs to be replaced?

[mcgahey]

Does anyone have the procedure to dismantle the dash in order to remove the mode door motor? I understand that it is located next to the heater blower.

[mcgahey]

I tested the mode motor actuator, it is getting power but does not kick on. The part is no longer in production and is unavailable. I guess I will attempt to disconnect the actuator and try to physically move the "mode door" from the vent position to the defrost position for winter operation. Buying a 12 volt fan and pointing it to the windshield might work as well.

Any ideas?

[Q451990]

http://www.car-part.com is a pretty good source for used parts, or check here for part-outs. I've heard of this problem a couple of times - in one of the cases, my local dealership had to find salvage parts. I'd find out what years used that same part by calling a dealership parts counter. I'm assuming it's 97-01, but I could be wrong.

Heath