Test F: Incorrect/Erratic Direction of Airflow From Outlet(s)

PINPOINT TEST F: INCORRECT/ERRATIC DIRECTION OF AIRFLOW FROM OUTLET(S)

F1-F2:

F2-F3:

F4-F5:

F6-F8:

F8-F10:

F10-F12:

F12-F13:

F13-F14:

F15-F16:

F16-F17:

F18-F19:

Normal Operation
Under normal operation, to rotate the mode door actuator, the electronic manual temperature control (EMTC), electronic automatic temperature control (EATC) or dual automatic temperature control (DATC) module supplies voltage to the Floor/Defrost/Panel mode door actuator motor through the circuit CH229 (WH/BU), and supplies ground through circuit CH228 (YE/GY). To reverse the mode door actuator rotation, the EMTC module or DATC/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 DATC/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.

Possible Causes
- An open, short to voltage, ground or together in circuits CH228 (YE/GY), CH229 (WH/BU), RH111 (GY/BU), LH111 (BN/WH) and VH436 (YE/VT)
- Floor/defrost/panel mode door actuator motor
- DATC/EATC module
- EMTC module
- Stuck or bound linkage or door