P0645

P0645-A/C CONTROL CIRCUIT/OPEN





For a complete wiring diagram consult Diagrams/Electrical


- When Monitored:
With the control circuit active and battery voltage greater than 10.4 volts.

- Set Condition:
The PCM detects an open or shorted condition in the (C13) A/C Clutch Relay Control circuit.







Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.Initial Inspection and Diagnostic Overview


Diagnostic Test


1. DTC IS ACTIVE
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 status Active for this DTC?

Yes


- Go to 2


No


- Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure.Checking For An Intermittent DTC




2. A/C CLUTCH CONTROL OPERATION
Turn the ignition off.
Disconnect the C5 TIPM harness connector.
With the scan tool, actuate the A/C Compressor Clutch Control State control to the ON position.
Using a 12 volt test light connected to 12 volts, check the (C13) A/C Clutch Control circuit in the C5 TIPM harness connector.

NOTE: If the DTC is active, the actuation test may not be allowed by the PCM. If may be necessary to clear the DTCs before starting the actuation.


NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

Is the test light illuminated and bright?

Yes


- Replace the TIPM.
- Perform the PCM Verification Test.Powertrain Verification Test


No


- Go to 3




3. (C13) A/C CLUTCH CONTROL CIRCUIT SHORTED TO GROUND
Turn the ignition off.
Disconnect the C3 PCM harness connector.
Measure the resistance between ground and the (C13) A/C Clutch Control circuit in the C5 TIPM harness connector.
Is the resistance below 100 ohms?

Yes


- Repair the (C13) A/C Clutch Control circuit for a short to ground.
- Perform the PCM Verification Test.Powertrain Verification Test


No


- Go to 4




4. (C13) A/C CLUTCH CONTROL CIRCUIT OPEN OR HIGH RESISTANCE
Measure the resistance of the (C13) A/C Clutch Control circuit between the C5 TIPM harness connector and the Powertrain Control Module (PCM) harness connector.
Is the resistance below 5.0 ohms?

Yes


- Go to 5


No


- Repair the (C13) A/C Clutch Control circuit for an open circuit or high resistance.
- Perform the PCM Verification Test.Powertrain Verification Test




5. POWERTRAIN CONTROL MODULE (PCM)
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the C5 TIPM harness connector and the Powertrain Control Module (PCM).
Look for any chafed, pierced, pinched, or partially broken wires.
Look for broken, bent, pushed out or corroded terminals.
Search for any Technical Service Bulletins that may apply.
Were any problems found?

Yes


- Repair as necessary.
- Perform the PCM Verification Test.Powertrain Verification Test


No


- Replace and program the Powertrain Control Module (PCM).
- Perform the PCM Verification Test.Powertrain Verification Test