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Pinpoint Test Q: Temperature Control Is Inoperative/Does Not Operate Correctly




Climate Control System

Pinpoint Tests

Pinpoint Test Q: Temperature Control is Inoperative/Does Not Operate Correctly

Refer to Wiring Diagram Set 55, Automatic Climate Control System for schematic and connector information. Diagrams By Number

Normal Operation

Under normal operation, to rotate the temperature blend door actuator, the HVAC module supplies voltage and ground to the temperature blend door actuators through the door actuator motor circuits. To reverse the temperature blend door actuator rotation, the HVAC module reverses the voltage and ground circuits.

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

During an actuator calibration cycle, the HVAC module drives the temperature blend door until the door reaches both internal stops in the HVAC case. If the temperature blend door is temporarily obstructed or binding during a calibration cycle, the HVAC module may interpret this as the actual end of travel for the door. When this condition occurs and the HVAC module commands the actuator to its end of travel, the airflow may not be the expected temperature.





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



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

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Q1 CHECK THE HVAC MODULE FOR DTCs


- Ignition ON.
- Check the HVAC module for DTCs.
- Are any DTCs present?

Yes
For DTC B1081:00 or B1082:00, INSPECT for binding/damaged linkage or door. REPAIR as necessary. If no condition is found, GO to Q3.

For DTC B1081:12 or B1082:12, GO to Q2.

For DTC B1081:11 or B1082:11, GO to Q4.

For DTC B11E5:15 or B11E6:15, GO to Q6.

For DTC B11E5:11 or B11E6:11, GO to Q10.

No
INSPECT for broken linkage or door. REPAIR as necessary. If no condition is found, GO to Q13.

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Q2 CHECK THE ACTUATOR MOTOR DRIVE CIRCUITS FOR A SHORT TO POWER


- Ignition OFF.
- Disconnect: HVAC Module C2356A.
- Disconnect: HVAC Module C2356B.
- Ignition ON.

For DTC B1081:12




- For DTC B1081:12, measure the voltage between ground and:
- HVAC module C2356A-18, circuit CH238 (YE/OG), harness side.
- HVAC module C2356A-19, circuit CH239 (BU/WH), harness side.

For DTC B1082:12




- For DTC B1082:12, measure the voltage between ground and:
- HVAC module C2356B-14, circuit CH212 (BU/OG), harness side.
- HVAC module C2356B-15, circuit CH213 (BN/GN), harness side.
- Are any voltages present?

Yes
REPAIR the circuit(s) for a short to power. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

No
GO to Q5.

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Q3 CHECK THE ACTUATOR MOTOR DRIVE CIRCUITS FOR AN OPEN


NOTE: Access to the connector in the following step is difficult. Before performing this step, visually inspect the actuator and its harness for obvious damage. If no damage is evident, proceed with the test.

- Ignition OFF.
- Disconnect: HVAC Module C2356A.
- Disconnect: HVAC Module C2356B.
- Disconnect: For DTC B1081:00, LH Temperature Blend Door Actuator C2091.
- Disconnect: For DTC B1082:00, RH Temperature Blend Door Actuator C2092 .

For DTC B1081:00




- For DTC B1081:00, measure the resistance between HVAC module C2356A, harness side and LH temperature blend door actuator C2091, harness side using the following chart:





For DTC B1082:00




- For DTC B1082:00, measure the resistance between HVAC module - DATC C2356B, harness side and RH temperature blend door actuator C2092, harness side using the following chart:





- Are the resistances less than 5 ohms?

Yes
GO to Q13.

No
REPAIR the circuit(s) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

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Q4 CHECK THE ACTUATOR MOTOR DRIVE CIRCUITS FOR A SHORT TO GROUND


- Ignition OFF.
- Disconnect: HVAC Module C2356A.
- Disconnect: HVAC Module C2356B.

For DTC B1081:11




- For DTC B1081:11, measure the resistance between ground and:
- HVAC module C2356A-18, circuit CH238 (YE/OG), harness side.
- HVAC module C2356A-19, circuit CH239 (BU/WH), harness side.

For DTC B1082:11




- For DTC B1082:11, measure the resistance between ground and:
- HVAC module C2356B-14, circuit CH212 (BU/OG), harness side.
- HVAC module C2356B-15, circuit CH213 (BN/GN), harness side.
- Are the resistances greater than 10,000 ohms?

Yes
GO to Q5.

No
REPAIR the circuit(s) for a short to ground. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

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Q5 CHECK THE ACTUATOR MOTOR DRIVE CIRCUITS FOR A SHORT TOGETHER


NOTE: Access to the connector in the following step is difficult. Before performing this step, visually inspect the actuator and its harness for obvious damage. If no damage is evident, proceed with the test.

- Ignition OFF.
- Disconnect: For DTC B1081:11, LH Temperature Blend Door Actuator C2091.
- Disconnect: For DTC B1082:11, RH Temperature Blend Door Actuator C2092 .

For DTC B1081:11




- For DTC B1081:11, measure the resistance between HVAC module C2356A-19, circuit CH239 (BU/WH), harness side and HVAC module C2356A-18, circuit CH238 (YE/OG), harness side.

For DTC B1082:11




- For DTC B1082:11, measure the resistance between HVAC module C2356B-15, circuit CH213 (BN/GN), harness side and HVAC module C2356B-14, circuit CH212 (BU/OG), harness side.
- Is the resistance greater than 10,000 ohms?

Yes
GO to Q13.

No
REPAIR circuit(s) for a short together. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

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Q6 CHECK CIRCUIT VH441 (WH/BN) OR VH440 (BU/BN) FOR AN OPEN


NOTE: Access to the connector in the following step is difficult. Before performing this step, visually inspect the actuator and its harness for obvious damage. If no damage is evident, proceed with the test.

- Ignition OFF.
- Disconnect: HVAC Module C2356A.
- Disconnect: HVAC Module C2356B.
- Disconnect: For DTC B11E5:15, LH Temperature Blend Door Actuator C2091.
- Disconnect: For DTC B11E6:15, RH Temperature Blend Door Actuator C2092 .
- Measure the resistance between the following:
- For DTC B11E5:15, HVAC module C2356A-7, circuit VH440 (BU/BN), harness side and LH temperature blend door actuator C2091-2, circuit VH440 (BU/BN), harness side.
- For DTC B11E6:15, HVAC module C2356B-24, circuit VH441 (WH/BN), harness side and RH temperature blend door actuator C2092-2, circuit VH441 (WH/BN), harness side.




- Is the resistance less than 5 ohms?

Yes
GO to Q7.

No
REPAIR circuit VH441 (WH/BN) or VH440 (BU/BN) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

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Q7 CHECK CIRCUIT VH440 (BU/BN) OR VH441 (WH/BN) FOR A SHORT TO POWER


- Ignition ON.
- Measure the voltage between ground and the following:
- For DTC B11E5:15, HVAC module C2356A-7, circuit VH440 (BU/BN), harness side.
- For DTC B11E6:15, HVAC module C228B-24, circuit VH441 (WH/BN), harness side.




- Is any voltage present?

Yes
REPAIR circuits VH441 (WH/BN) or VH440 (BU/BN) for a short to power. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

No
GO to Q8.

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Q8 CHECK CIRCUIT LH111 (BN/WH) FOR A SHORT TO CIRCUIT VH441 (WH/BN) OR VH440 (BU/BN)


- Ignition OFF.
- Measure the resistance between HVAC module C2356A-3, circuit LH111 (BN/WH) and the following:
- For DTC B11E5:15, HVAC module C2356A-7, circuit VH440 (BU/BN), harness side.
- For DTC B11E6:15, HVAC module C2356B-24, circuit VH441 (WH/BN), harness side.




- Is the resistance greater than 10,000 ohms?

Yes
GO to Q9.

No
REPAIR circuits LH111 (BN/WH) and VH441 (WH/BN) or circuit VH440 (BU/BN) for a short together. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

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Q9 CHECK THE ACTUATOR RETURN CIRCUIT RH111 (GY/BU) FOR AN OPEN


- Measure the resistance between HVAC module C2356A-4, circuit RH111 (GY/BU) and the following:
- For DTC B11E5:15, LH temperature blend door actuator C2091-3, circuit RH111 (GY/BU), harness side.
- For DTC B11E6:15, RH temperature blend door actuator C2092-3, circuit RH111 (GY/BU), harness side.




- Is the resistance less than 5 ohms?

Yes
GO to Q12.

No
REPAIR circuit RH111 (GY/BU) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

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Q10 CHECK CIRCUIT VH440 (BU/BN) OR VH441 (WH/BN) FOR A SHORT TO GROUND


- Ignition OFF.
- Disconnect: HVAC Module C2356A.
- Disconnect: HVAC Module C2356B.
- Measure the resistance between ground and the following:
- For DTC B11E5:11, HVAC module C2356A-7, circuit VH440 (BU/BN), harness side.
- For DTC B11E6:11, HVAC module C2356B-24, circuit VH441 (WH/BN), harness side.




- Are the resistances greater than 10,000 ohms?

Yes
GO to Q11.

No
REPAIR circuit VH441 (WH/BN) or VH440 (BU/BN) for a short to ground. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

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Q11 CHECK CIRCUIT RH111 (GY/BU) FOR A SHORT TO CIRCUIT VH441 (WH/BN) OR VH440 (BU/BN)


NOTE: Access to the connector in the following step is difficult. Before performing this step, visually inspect the actuator and its harness for obvious damage. If no damage is evident, proceed with the test.

- Disconnect: For DTC B11E5:11, LH Temperature Blend Door Actuator C2091.
- Disconnect: For DTC B11E6:11, RH Temperature Blend Door Actuator C2092 .
- Measure the resistance between HVAC module C2356A-4, circuit RH111 (GY/BU) and the following:
- For DTC B11E5:11, HVAC module C2356A-7, circuit VH440 (BU/BN), harness side.
- For DTC B11E6:11, HVAC module C2356B-24, circuit VH441 (WH/BN), harness side.




- Is the resistance greater than 10,000 ohms?

Yes
GO to Q13.

No
REPAIR circuits RH111 (GY/BU) and VH441 (WH/BN) or circuit VH440 (BU/BN) for a short together. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

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Q12 CHECK CIRCUIT LH111 (BN/WH) FOR AN OPEN


- Measure the resistance between HVAC module C2356A-3, circuit LH111 (BN/WH) and the following:
- For DTC B11E5:15, LH temperature blend door actuator C2091-1, circuit LH111 (BN/WH), harness side.
- For DTC B11E6:15, RH temperature blend door actuator C2092-1, circuit LH111 (BN/WH), harness side.




- Are the resistances less than 5 ohms?

Yes
GO to Q13.

No
REPAIR circuit LH111 (BN/WH) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

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Q13 CHECK THE ACTUATOR CONNECTION


- Disconnect the actuator connector.
- Check for:
- corrosion.
- pushed-out terminals.
- damaged terminals.
- Connect and correctly seat the actuator connector.
- Clear the DTCs.
- Operate the system and verify the concern is still present.
- Is the concern still present?

Yes
CARRY OUT the Temperature Blend Door Actuator component test. If the actuator tests OK, GO to Q14.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.

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Q14 MODULE ACTUATOR POSITION CALIBRATION


NOTE: The purpose of the module actuator position calibration is to allow the HVAC module to reinitialize and calibrate the actuator stop points. To carry out the calibration, follow the steps below.

- Ignition OFF.
- Inspect the module connectors for:
- corrosion.
- pushed-out terminals.
- damaged terminals.
- Connect and correctly seat all the HVAC module connectors.
- Ignition ON.
- Clear the DTCs.
- Select any position except OFF
- NOTE: The HVAC module will now initialize and calibrate the actuators. Calibration of the actuators will take approximately 30 seconds.
- Operate the system and verify the concern is still present.
- Is the concern still present?

Yes
INSTALL a new HVAC module. TEST the system for normal operation.

No
The system is now operating correctly at this time. The concern may have been caused by a foreign object in the HVAC case or temporary binding that restricted actuator door travel. CHECK any actuator external linkage. If condition recurs,
INSPECT actuator linkage and door for binding and CHECK HVAC case for foreign objects.

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