P0645

P0645-A/C CLUTCH CONTROL CIRCUIT





For a complete wiring diagram refer to Diagrams/Electrical.


- When Monitored:

With the ignition on. Battery voltage greater than 10 volts. A/C Switch on.

- Set Condition:

An open or shorted condition is detected in the A/C clutch control circuit. One Trip Fault. Three good trips to turn off the MIL.







Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.


Diagnostic Test


1. ACTIVE DTC

Turn the ignition on.

With the scan tool, Clear DTCs in the Powertrain Control Module (PCM).

With the scan tool, actuate the A/C Compressor Clutch Relay Control State.

With the scan tool, select View DTCs.

Is the DTC Active at this time?

Yes

- Go To 2

No

- Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Intermittent Condition


2. (C13) A/C CLUTCH CONTROL CIRCUIT SHORTED TO VOLTAGE





Stop the A/C Clutch actuation.

Turn the ignition off.

Disconnect the C3 PCM harness connector.

Disconnect the C1 TIPM harness connector.

Ignition on, engine not running.

Measure the voltage on the (C13) A/C Clutch Control circuit at the C1 TIPM harness connector.

Is there any voltage present?

Yes

- Repair the short to voltage in the (C13) A/C Clutch Control circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Go To 3


3. (C13) A/C CLUTCH CONTROL CIRCUIT OPEN





Turn the ignition off.


CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis.

Measure the resistance of the (C13) A/C Clutch Control circuit from the C1 TIPM harness connector to the appropriate terminal of special tool #8815.

Is the resistance below 5.0 ohms?

Yes

- Go To 4

No

- Repair the open in the (C13) A/C Clutch Control circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test


4. (C13) A/C CLUTCH CONTROL CIRCUIT SHORTED TO GROUND





Measure the resistance between ground and the (C13) A/C Clutch Control circuit at the C1 TIPM harness connector.

Is the resistance below 5.0 ohms?

Yes

- Repair the short to ground in the (C13) A/C Clutch Control circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Go To 5


5. A/C CLUTCH CONTROL OPERATION FROM THE PCM





Turn the ignition off.

Connect the C3 PCM harness connector.

Ignition on, engine not running.

Using the scan tool in the PCM, actuate the A/C Clutch.

With a 12-volt test light connected to ground, probe the (C13) A/C Clutch Control circuit in the C1 TIPM harness connector.

Does the test light illuminate brightly and flash on an off?

Yes

-
NOTE: Before continuing, check the TIPM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.
If OK, replace the TIPM.

No

- Go To 6


6. PCM

NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.

Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.

Were there any problems found?

Yes

- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Replace and program the Powertrain Control Module.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test