Pinpoint Test 2: Incorrect/Erratic Direction Of Airflow From Outlets

PINPOINT TEST 2: INCORRECT/ERRATIC DIRECTION OF AIRFLOW FROM OUTLETS

Normal Operation

To rotate the mode door actuator clockwise, the electronic manual temperature control (EMTC) module supplies voltage to the FLOOR/DEFROST/PANEL mode door actuator motor through circuit (Y/GY), and supplies ground through circuit (W/L). To rotate the mode door actuator counterclockwise, the EMTC module reverses the voltage and ground circuits.The mode door actuator feedback resistor is supplied a ground from the EMTC module through circuit (GY/L) and a 5-volt reference voltage on circuit (BR/W). The EMTC module reads the voltage on the mode door actuator feedback circuit (Y/V) to determine the mode door actuator position by the position of the actuator feedback resistor wiper arm.





Possible Causes
- Wiring, terminals or connectors
- Mode door actuator
- EMTC module
- Stuck or damaged linkage or door

Diagnostic Procedure