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




Climate Control System

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

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.

The temperature blend door actuator feedback resistor(s) is are supplied a 5-volt reference voltage and ground from the HVAC module. The HVAC module measures the resistance on the temperature blend door actuator feedback circuit 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 from the expected outlets.





This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors

- Temperature blend door actuator(s)

- HVAC module

- Temperature blend door(s) is binding or stuck

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

O1 CHECK THE HVAC MODULE FOR DTCs

- Ignition ON.

- Check the HVAC module for DTCs.

Are DTCs present?

Yes

For DTC B1081:07 or B1082:07, INSPECT for binding/damaged linkage or door. REPAIR as necessary. If no condition is found, INSTALL a new door actuator. CONNECT the actuator electrical connector before the HVAC module connector(s).
This will allow the new actuator to be calibrated when the HVAC module is reconnected. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

For DTC B1081:12 or B1082:12, GO to O2.

For DTC B1081:13 or B1082:13, GO to O3.

For DTC B1081:11 or B1082:11, GO to O4.

For DTC B11E5:15 or B11E6:15, GO to O6.

For DTC B11E5:11 or B11E6:11, GO to O10.

No
INSPECT for broken linkage or door. REPAIR as necessary. If no condition is found, GO to O13.

O2 CHECK THE TEMPERATURE BLEND DOOR ACTUATOR MOTOR CIRCUITS FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: HVAC Module C228A/C2356A.

- Disconnect: HVAC Module C228B/C2356B.

- Ignition ON.

- Measure the voltage between ground and:
- For DTC B1081:12, HVAC module C228A/C2356A-22, circuit CH238 (YE/OG), harness side.

- For DTC B1082:12, HVAC module C228B/C2356B-26, circuit CH212 (BU/OG), harness side.






- Measure the voltage between ground and:
- For DTC B1081:12, HVAC module C228A/C2356A-21, circuit CH239 (BU/WH), harness side.

- For DTC B1082:12, HVAC module C228B/C2356B-25, 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 O5.

O3 CHECK THE TEMPERATURE BLEND DOOR ACTUATOR MOTOR 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 C228A/C2356A.

- Disconnect: HVAC Module C228B/C2356B.

- Disconnect: For DTC B1081:13, LH Blend Door Actuator C2091.

- Disconnect: For DTC B1082:13, RH Blend Door Actuator C2092.

- Measure the resistance between:
- For DTC B1081:13, HVAC module C228A/C2356A-22, circuit CH238 (YE/OG), harness side and LH blend door actuator C2091-6, circuit CH238 (YE/OG), harness side.

- For DTC B1082:13, HVAC module C228B/C2356B-26, circuit CH212 (BU/OG), harness side and RH blend door actuator C2092-6, circuit CH212 (BU/OG), harness side.






- Measure the resistance between:
- For DTC B1081:13, HVAC module C228A/C2356A-21, circuit CH239 (BU/WH), harness side and LH blend door actuator C2091-5, circuit CH239 (BU/WH), harness side.

- For DTC B1082:13, HVAC module C228B/C2356B-25, circuit CH213 (BN/GN), harness side and RH blend door actuator C2092-5, circuit CH213 (BN/GN), harness side.






Are the resistances less than 5 ohms?

Yes
GO to O13.

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

O4 CHECK THE TEMPERATURE BLEND DOOR ACTUATOR MOTOR CIRCUITS FOR A SHORT TO GROUND

- Ignition OFF.

- Disconnect: HVAC Module C228A/C2356A.

- Disconnect: HVAC Module C228B/C2356B.

- Measure the resistance between ground and:
- For DTC B1081:11, HVAC module C228A/C2356A-22, circuit CH238 (YE/OG), harness side.

- For DTC B1082:11, HVAC module C228B/C2356B-26, circuit CH212 (BU/OG), harness side.






- Measure the resistance between ground and:
- For DTC B1081:11, HVAC module C228A/C2356A-21, circuit CH239 (BU/WH), harness side.

- For DTC B1082:11, HVAC module C228B/C2356B-25, circuit CH213 (BN/GN), harness side.






Are the resistances greater than 10,000 ohms?

Yes
GO to O5.

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

O5 CHECK THE TEMPERATURE BLEND DOOR ACTUATOR MOTOR 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 Blend Door Actuator C2091.

- Disconnect: For DTC B1082:11, RH Blend Door Actuator C2092.

- DTC B1081:11





NOTE: For DTC B1081:11.

Measure the resistance between HVAC module C228A/C2356A-21, circuit CH239 (BU/WH), harness side and HVAC module C228A/C2356A-22, circuit CH238 (YE/OG), harness side.

- DTC B1082:11





NOTE: For DTC B1082:11.

Measure the resistance between HVAC module C228B/C2356B-25, circuit CH213 (BN/GN), harness side and HVAC module C228B/C2356B-26, circuit CH212 (BU/OG), harness side.

Is the resistance greater than 10,000 ohms?

Yes
GO to O13.

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

O6 CHECK THE TEMPERATURE BLEND DOOR ACTUATOR FEEDBACK 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 C228A/C2356A.

- Disconnect: HVAC Module C228B/C2356B.

- Disconnect: For DTC B11E5:15, LH Blend Door Actuator C2091.

- Disconnect: For DTC B11E6:15, RH Blend Door Actuator C2092.

- Measure the resistance between the following:
- For DTC B11E5:15, HVAC module C228A/C2356A-7, circuit VH440 (BU/BN), harness side and LH blend door actuator C2091-2, circuit VH440 (BU/BN), harness side.

- For DTC B11E6:15, HVAC module C228B/C2356B-16, circuit VH441 (WH/BN), harness side and RH blend door actuator C2092-2, circuit VH441 (WH/BN), harness side.






Is the resistance less than 5 ohms?

Yes
GO to O7.

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.

O7 CHECK THE TEMPERATURE BLEND DOOR ACTUATOR FEEDBACK CIRCUIT(S) FOR A SHORT TO VOLTAGE

- Ignition ON.

- Measure the voltage between ground and the following:
- For DTC B11E5:15, HVAC module C228A/C2356A-7, circuit VH440 (BU/BN), harness side.

- For DTC B11E6:15, HVAC module C228B/C2356B-16, circuit VH441 (WH/BN), harness side.






Is any voltage present?

Yes
REPAIR circuit 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 O8.

O8 CHECK THE REFERENCE VOLTAGE CIRCUIT FOR A SHORT TO THE TEMPERATURE BLEND DOOR ACTUATOR FEEDBACK CIRCUITS

- Ignition OFF.

- Measure the resistance between HVAC module C228A/C2356A-11, circuit LH111 (BN/WH) and the following:
- For DTC B11E5:15, HVAC module C228A/C2356A-7, circuit VH440 (BU/BN), harness side.

- For DTC B11E6:15, HVAC module C228B/C2356B-16, circuit VH441 (WH/BN), harness side.






Is the resistance greater than 10,000 ohms?

Yes
GO to O9.

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

O9 CHECK THE TEMPERATURE BLEND DOOR ACTUATOR RETURN THE SIGNAL RETURN CIRCUIT FOR AN OPEN

- Measure the resistance between HVAC module C228A/C2356A-10, circuit RH107 (GN/BU) and the following:
- For DTC B11E5:15, LH blend door actuator C2091-3, circuit RH107 (GN/BU), harness side.

- For DTC B11E6:15, RH blend door actuator C2092-3, circuit RH107 (GN/BU), harness side.






Is the resistance less than 5 ohms?

Yes
GO to O13.

No
REPAIR circuit RH107 (GN/BU) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

O10 CHECK THE TEMPERATURE BLEND DOOR ACTUATOR FEEDBACK CIRCUIT(S) FOR A SHORT TO GROUND

- Ignition OFF.

- Disconnect: HVAC Module C228A/C2356A.

- Disconnect: HVAC Module C228B/C2356B.

- Measure the resistance between ground and the following:
- For DTC B11E5:11, HVAC module C228A/C2356A-7, circuit VH440 (BU/BN), harness side.

- For DTC B11E6:11, HVAC module C228B/C2356B-16, circuit VH441 (WH/BN), harness side.






Are the resistances greater than 10,000 ohms?

Yes
GO to O11.

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.

O11 CHECK THE SIGNAL RETURN CIRCUIT FOR A SHORT TO THE TEMPERATURE BLEND DOOR ACTUATOR FEEDBACK CIRCUIT

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 Blend Door Actuator C2091.

- Disconnect: For DTC B11E6:11, RH Blend Door Actuator C2092.

- Measure the resistance between HVAC module C228A/C2356A-10, circuit RH107 (GN/BU) and the following:
- For DTC B11E5:11, HVAC module C228A/C2356A-7, circuit VH440 (BU/BN), harness side.

- For DTC B11E6:11, HVAC module C228B/C2356B-16, circuit VH441 (WH/BN), harness side.






Is the resistance greater than 10,000 ohms?

Yes
GO to O12.

No
REPAIR circuits RH107 (GN/BU) and VH441 (WH/BN) or VH440 (BU/BN) for a short together. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

O12 CHECK THE REFERENCE VOLTAGE CIRCUIT FOR AN OPEN

- Measure the resistance between HVAC module C228A/C2356A-11, circuit LH111 (BN/WH) and the following:
- For DTC B11E5:11, LH blend door actuator C2091-1, circuit LH111 (BN/WH), harness side.

- For DTC B11E6:11, RH blend door actuator C2092-1, circuit LH111 (BN/WH), harness side.






Are the resistances less than 5 ohms?

Yes
GO to O13.

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

O13 CHECK THE TEMPERATURE BLEND DOOR ACTUATOR CONNECTION

- Disconnect the temperature blend door 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 blend door actuator component test. If a new actuator is installed, CONNECT the actuator electrical connector before the HVAC module connector(s). This will allow the new actuator to be calibrated when the HVAC module is reconnected. If the actuator tests OK, GO to O14. Component Tests and General Diagnostics

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. TEST the system for normal operation.

O14 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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