Re: It's gettin' HOT in here!!!
I got to the bottom of this problem at the weekend, following a tip off on a rival site, it turn out to be the actuator motor which operates the mixed air damper (temperature control) mounted on the side of the air plenum behind the dash.
The motor had seized. Remove the unit, and remove the small motor and tested independently of the circuit board. The motor was running fine, so stuck it back in, but still no joy. Remove the unit again, and inspected the circuit board for dry soldier joints, but all were fine. The only thing which stood out was the large amount of butter coloured grease in the unit, especially on some of the resistors anf circuit board. Cleant this off and replaced the unit again, And it started up fine.
IMHO i think it was a simple problem to the 155 wiper motor control problem, in that too much grease is applied.
I hope this is of help to others in a similiar position. BTW the small nuts holding the unit in are 5.5mm in size.