HVAC Mode Door Stall

Test 1:

Test 2 - 6:

Test 7 - 11:

Test 12 - 13:

SYMPTOM
HVAC MODE DOOR STALL

WHEN MONITORED
With the ignition key on and battery voltage greater than 10 volts.

SET CONDITION
The mode door fails to indicate a stall condition during motor calibration or during failed feedback calibration.

POSSIBLE CAUSES
- BCM HVAC failure pretest
- HVAC control head - ground circuit open
- HVAC mode sense circuit open
- Mode door driver (+) circuit short to B+
- Mode door driver (-) circuit short to ground
- HVAC control head mode sense defective
- Mode door driver (+) circuit open
- Mode door driver (-) circuit open
- Mode door driver (-) circuit short to B+
- Mode door actuator drive defective
- Mode door actuator linkage bind
- BCM - mode door driver defective
- BCM - mode sense defective
- Mode door actuator default