Test F: Incorrect/Erratic Direction Of Airflow From Outlets

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

Normal Operation
Under normal operation, to rotate the mode door actuator clockwise, the electronic manual temperature control (EMTC) module or electronic automatic temperature control (EATC) module supplies voltage to the FLOOR/DEFROST/PANEL mode door actuator motor through the circuit CH228 (YE/GY), and supplies ground through circuit CH229 (WH/BU). To rotate the mode door actuator counterclockwise, the EMTC module or EATC module reverses the voltage and ground circuits.

The mode door actuator feedback resistor is supplied a ground from the EMTC module or EATC module through circuit RH111 (GY/BU) and a 5-volt reference voltage on circuit LH111 (BN/WH). The EMTC module or EATC module reads the voltage on the mode door actuator feedback circuit VH436 (YE/VT) to determine the mode door actuator position by the position of the actuator feedback resistor wiper arm.

- DTC B1003 Mode Door Short/Failure - The module senses no change in actuator feedback voltage when the actuator motor has been energized.

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Mode door actuator
- EATC module
- EMTC module
- Stuck or bound linkage or door

F1-F2:

F2-F3:

F4-F5:

F6-F8:

F8-F10:

F10-F12:

F12-F13:

F14-F15:

F16-F18:

F18-F19: