Test M: Temperature Control Is Inoperative/Does Not Operate Correctly

PINPOINT TEST M: TEMPERATURE CONTROL IS INOPERATIVE/DOES NOT OPERATE CORRECTLY

Normal Operation
Under normal operation, to rotate the blend door actuator clockwise, the electronic manual temperature control (EMTC) module or HVAC module - dual automatic temperature control (DATC) 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 - DATC reverses the voltage and ground circuits.

The blend door actuator feedback resistors are supplied a ground from the HVAC module - EMTC or HVAC module - DATC 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 - DATC 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
- LH blend - CH238 (YE/OG)
- RH blend - CH213 (BN/GN)

Door actuator feed B circuits
- LH blend - CH239 (BU/WH)
- RH blend - CH212 (BU/OG)

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

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

Door actuator feedback circuits
- LH blend - VH440 (BU/BN)
- RH blend - VH441 (WH/BN)

- DTC B2266 LH Blend Door Failure or Short - The module senses no change in actuator feedback voltage when the actuator motor has been energized.
- DTC B2267 RH Blend Door Failure or Short - The module senses no change in actuator feedback voltage when the actuator motor has been energized.

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

M1-M2:

M3-M4:

M5-M7:

M7-M9:

M9-M11:

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