Test A: DTC B2266 Or DTC B2267 - Blend Door Failure Or Short

PINPOINT TEST A: DTC B2266 OR DTC B2267 - BLEND DOOR FAILURE OR SHORT

A1:

A1 Continued:

A2-A3:

A3-A5:

A5-A7:

A7-A9:

A9-A10:

A11-A13:

A13-A14:

A15-A17:

A18-A19:

A20-A21:

Normal Operation
Under normal operation, the driver side (LH) and passenger side (RH) temperature blend door actuator motors are supplied voltage or ground on circuit 245 (BN/LG) (LH) or circuit 1125 (BN) (RH), depending on desired actuator rotation, by the electronic automatic temperature control (EATC) module. The EATC module then supplies the appropriate voltage or ground to the other side of the actuator motor on circuit 246 (VT) (LH) or circuit 1124 (WH) (RH).

The driver side (LH) and passenger side (RH) temperature blend door actuator feedback resistors are supplied a ground from the EATC module by circuit 438 (RD/WH) and a 5 volt reference voltage on circuit 436 (RD/LG). The EATC module reads the voltage on circuit 437 (RD/WH) (LH) or circuit 1122 (RD) (RH) to determine the actuator position by the position of the actuator feedback resistor wiper arm.

Possible Causes
- An open, short to voltage, ground or together in circuits 245 (BN/LG), 246 (VT), 436 (RD/LG), 437 (RD/WH), 438 (RD/WH), 1124 (WH) or 1125 (BN)
- Driver side (LH) or passenger side (RH) temperature blend door actuator
- Electronic automatic temperature control (EATC) module
- Stuck or bound linkage or door