Test A: DTC B1239 - Air Flow Blend Door Driver Circuit Failure

PINPOINT TEST A: DTC B1239 - AIR FLOW BLEND DOOR DRIVER CIRCUIT FAILURE

A1:

A2-A3:

A4-A6:

A6-A8:

A8-A10:

Normal Operation
When the outside ambient air temperature is sufficient to provide adequate high-voltage battery cooling, the traction battery control module (TBCM) positions the auxiliary air inlet mode door actuator in the OPEN position. If the outside ambient air temperature is insufficient to provide adequate high voltage traction battery (HVTB) cooling, the TBCM positions the auxiliary air inlet mode door actuator in the CLOSED position and requests A/C cooling. The TBCM sends and receives signals to the auxiliary air inlet mode door actuator on circuits 1128 (GY/LB), 1129 (BN/WH) and 1130 (PK/LG), indicating the position of the auxiliary air inlet mode door. The TBCM controls the movement of the door by controlling power and ground to the auxiliary air inlet mode door actuator through circuits 698 (RD) and 699 (OG).

Possible Causes
- Circuit 699 (OG) open, short to voltage or short to ground
- Circuit 698 (RD) open, short to voltage or short to ground
- Circuit 1128 (GY/LB) open, short to voltage or short to ground
- Circuit 1129 (BN/WH) open, short to voltage or short to ground
- Circuit 1130 (PK/LG) open, short to voltage or short to ground
- Auxiliary air inlet mode door actuator
- Broken or binding air inlet door
- TBCM