Test L: Temperature Control Is Inoperative/Does Not Operate Correctly - Vehicles Equipped With Electric Heater

PINPOINT TEST L: TEMPERATURE CONTROL IS INOPERATIVE/DOES NOT OPERATE CORRECTLY - VEHICLES EQUIPPED WITH ELECTRIC HEATER

Normal Operation
Under normal operation, to rotate the blend door actuator clockwise, the HVAC module - electronic manual temperature control (EMTC) or HVAC module - electronic automatic temperature control (EATC) supplies voltage to the blend door actuator motors through the door actuator feed A circuits, and supplies ground through the door actuator feed B circuits. To rotate the blend door actuator counterclockwise, the HVAC module - EMTC or HVAC module - EATC reverses the voltage and ground circuits.

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

Door actuator feed A circuits
- (EMTC) blend - CH234 (YE/GN)
- (EATC) LH blend - CH239 (BU/WH)
- (EATC) RH blend - CH211 (YE)

Door actuator feed B circuits
- (EMTC) blend - CH233 (VT/BN)
- (EATC) LH blend - CH237 (VT/GY)
- (EATC) RH blend - CH213 (BN/GN)

Door actuator return circuits
- (EMTC) blend - RH111 (GY/BU)
- (EATC) LH blend - RH111 (GY/BU)
- (EATC) RH blend - RH111 (GY/BU)

Door actuator reference circuits
- (EMTC) blend - LH111 (BN/WH)
- (EATC) LH blend - LH111 (BN/WH)
- (EATC) RH blend - LH111 (BN/WH)

Door actuator feedback circuits
- (EMTC) blend - VH439 (GY/VT)
- (EATC) LH blend - VH440 (BU/BN)
- (EATC) RH blend - VH441 (WH/BN)

- DTC B2266 Left Side Blend Door Circuit Failure - The module senses no change in actuator feedback voltage when the actuator motor has been energized.
- DTC B2267 Right Side Blend Door Circuit Failure - The module senses no change in actuator feedback voltage when the actuator motor has been energized.

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Blend door actuator
- HVAC module - EATC
- HVAC module - EMTC
- Stuck or bound linkage or door

L1:

L2-L4:

L4-L6:

L6-L8:

L8-L10:

L10-L12:

L12 Continued:

L13-L14:

L14 Continued:

L15-L16:

L16-L17:

L17-L18: