93 850GLT HVAC

Hi Folks...

I'd appreciate some feedback on an hvac issue with my wife's 850. The
door [floor, vent, defrost, etc.] function is not operating. Fan spped,
heat and AC are fine. There are multiple DTC's recorded, most relating
to door motor circuits open or shorted to ground, except for "intake
air motor seized" [DTC 414 I believe]. My schematic and diagnostic
information is coming from Snap-On Shop Key, limited information at
best. My intuition suggests that a seized/shorted fan motor might
bollox up the rest of that circuit leading to multiple overlapping
DTCs. I'm a 240 guy with the usual aversion to tearing out half the
dash to repair a fan motor. Any thoughts before I dive in ?

thanks wharf rat

 

There's small controller that regulates the infinite speed adjustment
for the motor that usually fails when the current draw from the motor
becomes excessive. Pop out the glove box, underdash panel and knee
bolster...the blower motor is right there. Pull it out and turn it by
hand, if it seems stiff at all replace it. If it still doesn't work at
all replace the controller.

Bob