Here's my issue. Got an '02 TB LS. Couldn't get the mode control door to go to any defrost mode without the dreaded clicking. It would only blow air out the floor, face or floor and face vents. Found the Mode Control Actuator had a chipped off tooth and have resolved that issue. More on this later. While I've been wrenching and learning the system I have discovered the defrost actuator is not commanding the door to move. I pulled the actuator apart and did some wiring checks and the feed back potentiometer checks out as well as the motor. I then removed the motor wires from the circuit board and ran the motor manually with jumpers and the battery. That works too. Plug it back together and plug the actuator into the TB and it won't work. Tried recalibration, no help. Now for the kicker. I took the defrost actuator and plugged it into the left heat control plug and it works as advertised. WTF? I'm guessing a computer issue? And if it's a computer issue, is it the control head? I haven't dug into my manuals yet, this site is way more informative than any manual could be. Any help appreciated.
Since I haven't been able to get the defrost actuator to operate in it's own position, I took the needed gear out and used it in the mode control actuator for a temp fix until the new actuators get here. Also, must of had a piece of debris in the door as well, as I had to use a pair of pliers to get the door to go to it's full CW rotation position. Moves smoothly now, and works as it should.
Keith
Since I haven't been able to get the defrost actuator to operate in it's own position, I took the needed gear out and used it in the mode control actuator for a temp fix until the new actuators get here. Also, must of had a piece of debris in the door as well, as I had to use a pair of pliers to get the door to go to it's full CW rotation position. Moves smoothly now, and works as it should.
Keith
