Mode Door Output Shorted To Ground

NOTE: After making any repairs, perform BODY VERIFICATION TEST under VERIFICATION TESTS.

NOTE: After repair or replacement is completed, calibration must be performed. See AUTOMATIC A/C-HEATER SYSTEMS - CONCORDE, INTREPID & 300M article in HVAC.

Monitored & Set Condition

When Monitored: Whenever the BCM attempts to move one of the HVAC actuators.
Set Condition: When the BCM detects one or more of the following outputs shorted to ground: mode door driver, blend door driver, recirculation door driver or the common door driver.

Possible Causes:

Testing

Turn all lights off. Close the driver door latch to turn courtesy lights off. Disconnect BCM C1 harness connector. See Figure . Measure the resistance between ground and the mode door driver circuit. If the resistance is 5 ohms or less, repair the mode door driver circuit for a short to ground. If the resistance is 5 ohms or more, go to next step.
Measure the resistance between the mode door driver circuit and the sensor ground circuit in the BCM C1 connector. If the resistance is 5 ohms or less, go to next step. If the resistance is 5 ohms or more, replace the BCM. See BODY CONTROL MODULE under REMOVAL & INSTALLATION.
Disconnect the mode door actuator harness connector. Measure the resistance between the mode door driver circuit and the sensor ground circuit in the BCM C1 connector. If the resistance is 5 ohms or less, repair the mode door driver circuit for a short to the sensor ground circuit. If the resistance is 5 ohms or more, replace the mode door actuator. See MODE DOOR ACTUATOR under REMOVAL & INSTALLATION.