P0645

P0645-A/C CLUTCH CONTROL CIRCUIT





For complete wiring diagrams 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. A/C CLUTCH OPERATION

Ignition on, engine not running.

With a scan tool, actuate the A/C Clutch.

Is the A/C Clutch actuating?

Yes

- Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Intermittent Condition
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Go To 2

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.

Does the voltmeter indicate 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