Test D: DTC B1242 Air Inlet Door Short/Failure

PINPOINT TEST D: DTC B1242 AIR INLET DOOR SHORT/FAILURE

D1-D2:

D2-D4:

D5-D7:

D7-D9:

D9-D11:

D11-D13:

D13-D14:

D14-D15:

D15-D17:

D17-D18:

D19:

Normal Operation
Under normal operation, to rotate the air inlet door actuator clockwise, the EMTC module or EATC module supplies voltage to the air inlet air inlet door actuator motor through the circuit 1990 (WH/LB), and supplies ground through circuit 1991 (LB/WH). To rotate the air inlet door actuator counterclockwise, the EATC module reverses the voltage and ground circuits.

NOTE: EATC only.

The air inlet door actuator feedback resistor is supplied a ground from the EATC module through circuit 438 (RD/WH) and a 5-volt reference voltage on circuit 436 (RD/LG). The EATC module reads the voltage on the air inlet door actuator feedback circuit 3053 (BN/WH) to determine the air inlet 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 1991 (LB/WH), 1990 (WH/LB), 438 (RD/WH), 436 (RD/LG) and 3053 (BN/WH)
- Air inlet door actuator motor
- EATC module
- EMTC module
- Stuck or bound linkage or door