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




Climate Control System

Pinpoint Tests

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

Refer to Wiring Diagram Set 54 (Escape/Mariner, Escape Hybrid/Mariner Hybrid), Manual Climate Control System for schematic and connector information. Diagrams By Number

Refer to Wiring Diagram Set 55 (Escape/Mariner, Escape Hybrid/Mariner Hybrid), 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 resistor is supplied a ground from the HVAC module 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 temperature may not be as warm or cold as expected.





This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Blend door actuator
- HVAC module - Dual Automatic Temperature Control (DATC)
- HVAC module - Electronic Manual Temperature Control (EMTC)
- Stuck or damaged linkage or door


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

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N1 CHECK THE HVAC MODULE FOR DTCs

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

Yes
For DTC B12B7, B12B8 or B12A2, INSPECT for binding/damaged linkage or door. REPAIR as necessary. If no condition is found, INSTALL a new door actuator. REFER to Climate Control Air Door Actuator / Motor. 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. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

For DTC B12B3, B129B or B129F, GO to N2.

For DTC B297A, B297C or B297E, GO to N3.

For DTC B297B, B297D or B297F, GO to N4.

For DTC B12B5, B129C or B12A0, GO to N6.

For DTC B12B6, B129D or B12A1, GO to N10.

No
CHECK that the A/C system pressure is above 290 kPa (42 psi). If the pressure is below 290 kPa (42 psi), REFER to Fluorescent Dye Leak Detection Fluorescent Dye Leak Detection. CHECK the temperature blend doors/actuators for a binding or broken condition. If no condition is found, GO to N13.

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N2 CHECK THE ACTUATOR MOTOR DRIVE CIRCUITS FOR A SHORT TO POWER

- Ignition OFF.
- Disconnect: HVAC Module - DATC C2356A and C2356B or HVAC Module - EMTC C2357A.
- Ignition ON.
- Measure the voltage between ground and:
- For DTC B12B3, HVAC module - EMTC C2357A-22, circuit CH238 (YE/OG), harness side.
- For DTC B129B, HVAC module - DATC C2356A-22, circuit CH238 (YE/OG), harness side.
- For DTC B129F, HVAC module - DATC C2356B-26, circuit CH212 (BU/OG), harness side.




- Measure the voltage between ground and:
- For DTC B12B3, HVAC module - EMTC C2357A-21, circuit CH239 (BU/WH), harness side.
- For DTC B129B, HVAC module - DATC C2356A-21, circuit CH239 (BU/WH), harness side.
- For DTC C129F, HVAC module - DATC C2356B-25, circuit CH213 (BN/GN), harness side.





- Is any voltage 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 N5.

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N3 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 - DATC C2356A and C2356B or HVAC Module - EMTC C2357A.
- Disconnect: For DTC B297A, Blend Door Actuator C289.
- Disconnect: For DTC B297C, LH Blend Door Actuator C2091.
- Disconnect: For DTC B297E, RH Blend Door Actuator C2092.
- Measure the resistance between:
- For DTC B297A, HVAC module - EMTC C2357A-22, circuit CH238 (YE/OG), harness side and LH blend door actuator C289-6, circuit CH238 (YE/OG), harness side.
- For DTC B297C, HVAC module - DATC C2356A-22, circuit CH238 (YE/OG), harness side and LH blend door actuator C2091-6, circuit CH238 (YE/OG), harness side.
- For DTC B297E, HVAC module - DATC 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 B297A, HVAC module - EMTC C2357A-21, circuit CH239 (BU/WH), harness side and LH blend door actuator C289-1, circuit CH239 (BU/WH), harness side.
- For DTC B297C, HVAC module - DATC C2356A-21, circuit CH239 (BU/WH), harness side and LH blend door actuator C2091-1, circuit CH239 (BU/WH), harness side.
- For DTC B297E, HVAC module - DATC C2356B-25, circuit CH213 (BN/GN), harness side and RH blend door actuator C2092-1, circuit CH213 (BN/GN), harness side.





- Are the resistances less than 5 ohms?

Yes
GO to N13.

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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N4 CHECK THE ACTUATOR MOTOR DRIVE CIRCUITS FOR A SHORT TO GROUND

- Ignition OFF.
- Disconnect: HVAC Module - DATC C2356A and C2356B or HVAC Module - EMTC C2357A.
- Measure the resistance between ground and:
- For DTC B297B, HVAC module - EMTC C2357A-22, circuit CH238 (YE/OG), harness side.
- For DTC B297D, HVAC module - DATC C2356A-22, circuit CH238 (YE/OG), harness side.
- For DTC B297F, HVAC module - DATC C2356B-26, circuit CH212 (BU/OG), harness side.




- Measure the resistance between ground and:
- For DTC B297B, HVAC module - EMTC C2357A-21, circuit CH239 (BU/WH), harness side.
- For DTC B297D, HVAC module - DATC C2356A-21, circuit CH239 (BU/WH), harness side.
- For DTC B297F, HVAC module - DATC C2356B-25, circuit CH213 (BN/GN), harness side.





- Are the resistances greater than 10,000 ohms?

Yes
GO to N5.

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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N5 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 B297B, Blend Door Actuator C289.
- Disconnect: For DTC B297D, LH Blend Door Actuator C2091.
- Disconnect: For DTC B297F, RH Blend Door Actuator C2092.

For DTC B297B or B297D





- For DTC B297B or B297D, measure the resistance between:
- For EMTC systems, HVAC module - EMTC C2357A-21, circuit CH239 (BU/WH), harness side and HVAC module - EMTC C2357A-22, circuit CH238 (YE/OG), harness side.
- For DATC systems, HVAC module - DATC C2356A-21, circuit CH239 (BU/WH), harness side and HVAC module - DATC C2356A-22, circuit CH238 (YE/OG), harness side.

For DTC B297F





- For DTC B297F, measure the resistance between HVAC module - DATC C2356B-25, circuit CH213 (BN/GN), harness side and HVAC module - DATC C2356B-26, circuit CH212 (BU/OG), harness side.
- Is the resistance greater than 10,000 ohms?

Yes
GO to N13.

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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N6 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 - DATC C2356A and C2356B or HVAC Module - EMTC C2357A.
- Disconnect: For DTC B12B5, Blend Door Actuator C289.
- Disconnect: For DTC B129C, LH Blend Door Actuator C2091.
- Disconnect: For DTC B12A0, RH Blend Door Actuator C2092.
- Measure the resistance between the following:
- For DTC B12B5, HVAC module - EMTC C2357A-7, circuit VH440 (BU/BN), harness side and LH blend door actuator C289-4, circuit VH440 (BU/BN), harness side.
- For DTC B129C, HVAC module - DATC C2356A-7, circuit VH440 (BU/BN), harness side and LH blend door actuator C2091-4, circuit VH440 (BU/BN), harness side.
- For DTC B12A0, HVAC module - DATC C2356B-24, circuit VH441 (WH/BN), harness side and RH blend door actuator C2092-4, circuit VH441 (WH/BN), harness side.





- Is the resistance less than 5 ohms?

Yes
GO to N7.

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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N7 CHECK CIRCUITS RH111 (GY/BU), VH440 (BU/BN) OR VH441 (WH/BN) FOR A SHORT TO POWER

- Ignition ON.
- Measure the voltage between ground and the following:
- HVAC module - EMTC C2357A-10 or HVAC module - DATC C2356A-10, circuit RH111 (GY/BU), harness side.
- For DTC B12B5, HVAC module - EMTC C2357A-7, circuit VH440 (BU/BN), harness side.
- For DTC B129C, HVAC module - DATC C2356A-7, circuit VH440 (BU/BN), harness side.
- For DTC B12A0, HVAC module - DATC C2356B-24, circuit VH441 (WH/BN), harness side.





- Are any voltages present?

Yes
REPAIR circuit RH111 (GY/BU), 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 N8.

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N8 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 - DATC C2356A-11 or HVAC module - EMTC C2357A-11, circuit LH111 (BN/WH) and the following:
- For DTC B12B5, HVAC module - EMTC C2357A-7, circuit VH440 (BU/BN), harness side.
- For DTC B129C, HVAC module - DATC C2356A-7, circuit VH440 (BU/BN), harness side.
- For DTC B12A0, HVAC module - DATC C2356B-24, circuit VH441 (WH/BN), harness side.





- Is the resistance greater than 10,000 ohms?

Yes
GO to N9.

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

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N9 CHECK THE ACTUATOR RETURN CIRCUIT RH111 (GY/BU) FOR AN OPEN

- Measure the resistance between HVAC module - DATC C2356A-10 or HVAC module - EMTC C2357A-10, circuit RH111 (GY/BU) and the following:
- For DTC B12B5, blend door actuator C289-2, circuit RH111 (GY/BU), harness side.
- For DTC B129C, LH blend door actuator C2091-2, circuit RH111 (GY/BU), harness side.
- For DTC B12A0, RH blend door actuator C2092-2, circuit RH111 (GY/BU), harness side.





- Is the resistance less than 5 ohms?

Yes
GO to N13.

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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N10 CHECK CIRCUIT LH111 (BN/WH), VH440 (BU/BN) OR VH441 (WH/BN) FOR A SHORT TO GROUND

- Ignition OFF.
- Disconnect: HVAC Module - DATC C2356A and C2356B or HVAC Module - EMTC C2357A.
- Measure the resistance between ground and the following:
- HVAC module - EMTC C2357A-11 or HVAC module - DATC C2356A-11, circuit LH111 (BN/WH), harness side.
- For DTC B12B6, HVAC module - EMTC C2357A-7, circuit VH440 (BU/BN), harness side.
- For DTC B129D, HVAC module - DATC C2356A-7, circuit VH440 (BU/BN), harness side.
- For DTC B12A1, HVAC module - DATC C2356B-24, circuit VH441 (WH/BN), harness side.





- Are the resistances greater than 10,000 ohms?

Yes
GO to N11.

No
REPAIR circuit LH111 (BN/WH), 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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N11 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 B12B6, Blend Door Actuator C289.
- Disconnect: For DTC B129D, LH Blend Door Actuator C2091.
- Disconnect: For DTC B12A1, RH Blend Door Actuator C2092.
- Measure the resistance between HVAC module - DATC C2356A-10 or HVAC module - EMTC C2357A-10, circuit RH111 (GY/BU) and the following:
- For DTC B12B6, HVAC module - EMTC C2357A-7, circuit VH440 (BU/BN), harness side.
- For DTC B129D, HVAC module - DATC C2356A-7, circuit VH440 (BU/BN), harness side.
- For DTC B12A1, HVAC module - DATC C2356B-24, circuit VH441 (WH/BN), harness side.





- Is the resistance greater than 10,000 ohms?

Yes
GO to N12.

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

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N12 CHECK CIRCUIT LH111 (BN/WH) FOR AN OPEN

- Measure the resistance between HVAC module - DATC C2356A-11 or HVAC module - EMTC C2357A-11, circuit LH111 (BN/WH) and the following:
- For DTC B12B6, blend door actuator C289-3, circuit LH111 (BN/WH), harness side.
- For DTC B129D, LH blend door actuator C2091-3, circuit LH111 (BN/WH), harness side.
- For DTC B12A1, RH blend door actuator C2092-3, circuit LH111 (BN/WH), harness side.





- Is the resistance less than 5 ohms?

Yes
GO to N13.

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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N13 CHECK THE ACTUATOR CONNECTION

- Inspect the blend door actuator connector 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. Blend Door Actuator 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 N14.

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.

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N14 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 HVAC 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. REFER to Climate Control Service and Repair. 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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