Test D: Incorrect/Erratic Direction Of Airflow From Outlet(s)

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

Test D1-D2:

Test D2-D3:

Test D4-D5:

Test D6-D8:

Test D8-D10:

Test D10-D12:

Test D12-D13:

Test D13-D14:

Test D14-D15:

Test D15-D16:

Test D16-D17:

Test D17-D18:

Test D18 Continued:

Normal Operation
Under normal operation, to rotate the mode door actuator clockwise, the EMTC module or EATC module supplies voltage to the Blend, Floor/Defrost and Panel mode door actuator motors through the door actuator feed B circuits, and supplies ground through the door actuator feed A circuits. To rotate the mode door actuator counterclockwise, the EMTC module or EATC module reverses the voltage and ground circuits.

The mode door actuator feedback resistors are supplied a ground from the EMTC module or EATC module by the mode door actuator return circuits and a 5-volt reference voltage on the mode door actuator reference circuits. The EMTC module or EATC module reads the voltage on the mode door actuator feedback circuits to determine the mode door actuator position by the position of the actuator feedback resistor wiper arm.

Door actuator feed B circuits
- Blend - 250 (OG)
- Floor/Defrost - 1997 (BN/YE)
- Panel - 1993 (BN/YE)

Door actuator feed A circuits
- Blend - 249 (DB/LG)
- Floor/Defrost - 1996 (LB/RD)
- Panel - 1992 (YE/LB)

Door actuator return circuits
- Blend - 247 (WH/YE)
- Floor/Defrost - 247 (WH/YE)
- Panel - 247 (WH/YE)

Door actuator reference circuits
- Blend - 243 (LG/OG)
- Floor/Defrost - 243 (LG/OG)
- Panel - 243 (LG/OG)

Door actuator feedback circuits
- Blend - 246 (VT)
- Floor/Defrost - 1990 (WH/LB)
- Panel - 1989 (OG/LB)

Possible Causes
- An open, short to voltage, ground or together in door actuator open, close, return, reference or feedback circuits
- Blend, air inlet, floor/defrost and panel mode door actuator motor
- EATC module
- Manual climate control module
- Stuck or bound linkage or door