Join Date: Aug 2009
Location: Gaithersburg, MD
Hmmmm... really puzzling! I would suggest the possibility of a faulty brush contact on the motor (presuming it has brushes) like you sometimes get on starter motors. Then, depending on where the motor stoped last time, results in start/no-start next time. A stretch though, maybe.
How about working backwards from symptoms... does everything else work fine (on the A/C controller) when the fan is stopped? What (if you know) gets the blower working again. Can you track any commonalities in working or not working?
UPDATE: Ahhhh, I just noticed something else. Power to the motor is supplied via the HVAC relay (#30 in the BCM). That relay is energised by some logic which (apparently) depends on the coolant level sensor. Are you sure your coolant level is good (or that sensor, or its wiring, is not suspect)? Also check that HVAC relay, make sure it's not loose.
Owner of "Campbelle", a Brazen 2008 GXP ... with mods piling up...
Last edited by TomatoSoup; 12-28-2012 at 06:45 PM.