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Pinpoint Test F: Incorrect/Erratic Direction Of Airflow From Outlets




Climate Control System

Pinpoint Tests

Pinpoint Test F: Incorrect/Erratic Direction of Airflow From Outlets

Refer to Wiring Diagram Set 54, Manual Climate Control System for schematic and connector information. Diagrams By Number

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 defrost/panel/floor mode door actuator, the HVAC module supplies voltage and ground to the defrost/panel/floor mode door actuator motor through the actuator motor circuits. To reverse the defrost/panel/floor mode door actuator rotation, the HVAC module reverses the voltage and ground circuits.

The defrost/panel/floor mode door actuator feedback resistor is supplied a 5-volt reference voltage and ground from the HVAC module. The HVAC module measures the resistance on the defrost/panel/floor mode door actuator feedback circuit to determine the defrost/panel/floor mode door actuator position by the position of the actuator feedback resistor wiper arm.

- DTC B1003 (Mode Door Short/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
- Mode door actuator
- HVAC module - Dual Automatic Temperature Control (DATC)
- HVAC module - Electronic Manual Temperature Control (EMTC)
- Stuck or bound linkage or door



PINPOINT TEST F: INCORRECT/ERRATIC DIRECTION OF AIRFLOW FROM OUTLETS

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F1 CHECK THE FEEDBACK POTENTIOMETER TOTAL RESISTANCE


- Ignition OFF.
- Disconnect: HVAC Module - DATC C228A or HVAC Module - EMTC C2357A.
- Measure the resistance between HVAC module - DATC C228A-11 or HVAC module - EMTC C2357A-11, circuit LH111 (BN/WH), harness side and HVAC module - DATC C228A-10 or HVAC module - EMTC C2357a-10, circuit RH111 (GY/BU), harness side.




- Is the resistance greater than 500 ohms?

Yes
GO to F5.

No
For vehicles not equipped with electric heater, GO to F2.

For vehicles equipped with electric heater, GO to F3.

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F2 CHECK THE DEFROST/PANEL/FLOOR DOOR ACTUATOR


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.

- Measure the resistance between HVAC module - DATC C228A-11 or HVAC module - EMTC C2357A-11, circuit LH111 (BN/WH), harness side and HVAC module - DATC C228A-10 or HVAC module - EMTC C2357a-10, circuit RH111 (GY/BU), harness side.




- While measuring the resistance above, disconnect the following components one at a time, in order. Stop disconnecting components if the measured resistance rises above 500 ohms.
- Defrost/panel/floor door actuator C2278
- For DATC systems only, RH blend door actuator C2092
- Did the resistance rise above 500 ohms?

Yes
For EMTC systems only, INSTALL a new defrost/panel/floor door actuator.

For DATC systems only, INSTALL a new actuator (the last one to be disconnected).

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.

No
Visually inspect the harness between the HVAC module and actuator for obvious damage. REPAIR as necessary. If no damage is evident, INSTALL a new LH 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. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

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F3 CHECK THE DEFROST/PANEL/FLOOR DOOR ACTUATOR


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: Defrost/Panel/Floor Door Actuator C2248.
- Measure the resistance between HVAC module - DATC C228A-11 or HVAC module - EMTC C2357A-11, circuit LH111 (BN/WH), harness side and HVAC module - DATC C228A-10 or HVAC module - EMTC C2357a-10, circuit RH111 (GY/BU), harness side.




- Is the resistance greater than 500 ohms?

Yes
INSTALL a new defrost/panel/floor door actuator. CONNECT the actuator electrical connector before the HVAC module electrical connector(s). This will allow the new actuator to be calibrated when the HVAC module is reconnected. TEST the system for normal operation.

No
GO to F4.

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F4 CHECK CIRCUITS RH111 (GY/BU) AND LH111 (BN/WH) FOR A SHORT TOGETHER


- Disconnect: Inline C214.
- Measure the resistance between HVAC module - DATC C228A-11 or HVAC module - EMTC C2357A-11, circuit LH111 (BN/WH), harness side and HVAC module - DATC C228A-10 or HVAC module - EMTC C2357a-10, circuit RH111 (GY/BU), harness side.




- Is the resistance greater than 500 ohms?

Yes
For EMTC systems only, visually INSPECT the harness between the actuator and inline C214 for obvious damage. REPAIR as necessary. If no damage is evident, INSTALL a new LH blend door actuator.

For DATC systems only, visually INSPECT the harness between the actuator and inline C214 for obvious damage. REPAIR as necessary. If no damage is evident, INSTALL a new LH blend door actuator and RH 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. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

No
REPAIR circuits LH111 (BN/WH) and RH111 (GY/BU) between HVAC module C228A and inline C214 for a short together. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

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F5 CHECK THE POTENTIOMETER LOW- AND HIGH-SIDE RESISTANCE


- Measure the low-side resistance between:
- For EMTC systems, HVAC module - EMTC C2357A-10, circuit RH111 (GY/BU), harness side and HVAC module - EMTC C2357A-8, circuit VH437 (VT/BN), harness side.
- For DATC systems, HVAC module - DATC C228A-10, circuit RH111 (GY/BU), harness side and HVAC module - DATC C228A-8, circuit VH436 (YE/VT), harness side.




- Measure the high-side resistance between:
- For EMTC systems, HVAC module - EMTC C2357A-11, circuit LH111 (BN/WH), harness side and HVAC module - EMTC C2357A-8, circuit VH437 (VT/BN), harness side.
- For DATC systems, HVAC module - DATC C228A-11, circuit LH111 (BN/WH), harness side and HVAC module - DATC C228A-8, circuit VH436 (YE/VT), harness side.




- Are the resistances between 187 and 6,563 ohms?

Yes
GO to F6.

No
CARRY OUT the Defrost/Panel/Floor Mode 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 and if the low-side resistance only is greater than 6,563 ohms, REPAIR circuit RH111 (GY/BU) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation. Floor/Defrost/Panel Mode Door Actuator

If the low-side resistance only is less than 187 ohms, REPAIR circuits VH436 (YE/VT) or VH437 (VT/BN) and RH111 (GY/BU) for a short together. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

If the high-side resistance only is greater than 6,563 ohms, REPAIR circuit LH111 (BN/WH) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

If the high-side resistance only is less than 187 ohms, REPAIR circuits VH436 (YE/VT) or VH437 (VT/BN) and LH111 (BN/WH) for a short together. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

If both the high-side and low-side resistance is greater than 6,563 ohms, REPAIR circuit VH436 (YE/VT) or VH437 (VT/BN) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

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F6 CHECK CIRCUIT RH111 (GY/BU), VH436 (YE/VT) OR VH437 (VT/BN) FOR A SHORT TO POWER


- Ignition ON.
- Measure the voltage between ground and the following:
- HVAC module - DATC C228A-10 or HVAC module - EMTC C2357A-10, circuit RH111 (GY/BU), harness side.
- HVAC module - DATC C228A-8, circuit VH436 (YE/VT), harness side or HVAC module - EMTC C2357A-8, circuit VH437 (VT/BN), harness side.




- Is any voltage present?

Yes
REPAIR circuit RH111 (GY/BU), VH436 (YE/VT) or VH437 (VT/BN) for a short to power. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

No
GO to F7.

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F7 CHECK CIRCUIT LH111 (BN/WH), VH436 (YE/VT) OR VH437 (VT/BN) FOR A SHORT TO GROUND


- Ignition OFF.
- Measure the resistance between ground and the following:
- HVAC module - DATC C228A-11 or HVAC module - EMTC C2357A-11, circuit LH111 (BN/WH), harness side.
- HVAC module - DATC C228A-8, circuit VH436 (YE/VT), harness side or HVAC module - EMTC C2357A-8, circuit VH437 (VT/BN), harness side.




- Are the resistances greater than 10,000 ohms?

Yes
GO to F8.

No
REPAIR circuit LH111 (BN/WH), VH436 (YE/VT) or VH437 (VT/BN) for a short to ground. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

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F8 CHECK THE DOOR ACTUATOR OPERATION


NOTE: If a jumper fuse opens while carrying out this test step, repair the circuit(s) for a short.

- Measure the resistance between:
- For EMTC systems, HVAC module - EMTC C2357A-10, circuit RH111 (GY/BU), harness side and HVAC module - EMTC C2357A-8, circuit VH437 (VT/BN), harness side.
- For DATC systems, HVAC module - DATC C228A-10, circuit RH111 (GY/BU), harness side and HVAC module - DATC C228A-8, circuit VH436 (YE/VT), harness side.




- Connect a fused jumper wire between:
- For EMTC systems, HVAC module - EMTC C2357A-13, circuit SBP15 (WH/RD), harness side and HVAC module - EMTC C2357A-19, circuit CH202 (BU/GN), harness side. Connect a second fused jumper wire between HVAC module - EMTC C2357A-23, circuit GD133 (BK), harness side and HVAC module - EMTC C2357A-20, circuit CH203 (GN/BN), harness side.
- For DATC systems, HVAC module - DATC C228A-13, circuit SBP15 (WH/RD), harness side and HVAC module - DATC C228A-19, circuit CH229 (WH/BU), harness side. Connect a second fused jumper wire between HVAC module - DATC C228A-23, circuit GD133 (BK), harness side and HVAC module - DATC C228A-20, circuit CH228 (YE/GY), harness side.




- Remove the fused jumpers.
- Connect a fused jumper wire between:
- For EMTC systems, HVAC module - EMTC C2357A-23, circuit GD133 (BK), harness side and HVAC module - EMTC C2357A-19, circuit CH202 (BU/GN), harness side. Connect a second fused jumper wire between HVAC module - EMTC C2357A-13, circuit SBP15 (WH/RD), harness side and HVAC module - EMTC C2357A-20, circuit CH203 (GN/BN), harness side.
- For DATC systems, HVAC module - DATC C228A-23, circuit GD133 (BK), harness side and HVAC module - DATC C228A-19, circuit CH229 (WH/BU), harness side. Connect a second fused jumper wire between HVAC module - DATC C228A-13, circuit SBP15 (WH/RD), harness side and HVAC module - DATC C228A-20, circuit CH228 (YE/GY), harness side.




- Does the resistance increase and decrease when the jumpers are connected?

Yes
INSPECT for broken door and linkage. REPAIR as necessary. If no condition is found, GO to F10.

No
GO to F9.

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F9 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.

- Disconnect: Defrost/Panel/Floor Door Actuator C2248.
- Measure the resistance between:
- For EMTC systems, HVAC module - EMTC C2357A-19, circuit CH202 (BU/GN), harness side and defrost/panel/floor door actuator C2248-1, circuit CH202 (BU/GN), harness side.
- For DATC systems, HVAC module - DATC C228A-19, circuit CH229 (WH/BU), harness side and defrost/panel/floor door actuator C2248-1, circuit CH229 (WH/BU), harness side.




- Measure the resistance between:
- For EMTC systems, HVAC module - EMTC C2357A-20, circuit CH203 (GN/BN), harness side and defrost/panel/floor door actuator C2248-6, circuit CH203 (GN/BN), harness side.
- For DATC systems, HVAC module - DATC C228A-20, circuit CH228 (YE/GY), harness side and defrost/panel/floor door actuator C2248-6, circuit CH228 (YE/GY), harness side.




- Are the resistances less than 1 ohm?

Yes
INSPECT for binding or broken linkage. REPAIR as necessary. If no condition is found, INSTALL a new door actuator. TEST the system for normal operation.

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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F10 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 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 F11. Temperature Blend Door Actuator

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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F11 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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