P0647-A/C CLUTCH CONTROL CIRCUIT HIGH





For a complete wiring diagram Refer to Section 8W

Theory of Operation


When the ignition switch is on, the Totally Integrated Power Module (TIPM) sends a 12 volt signal to the ECM on the A/C Compressor Clutch Control circuit. The ECM grounds this signal to indicate a request for A/C Compressor Clutch operation.



Possible Causes
INTERMITTENT DTC
(C13) A/C CLUTCH RELAY CONTROL CIRCUIT SHORTED TO VOLTAGE
(C13) A/C CLUTCH RELAY CONTROL CIRCUIT OPEN OR HIGH RESISTANCE
TOTALLY INTEGRATED POWER MODULE

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)



Diagnostic Test

1. DTC IS ACTIVE

Start and idle the engine.
With the scan tool, Clear DTCs in the Engine Control Module (ECM).
Attempt to turn the A/C system on.
Monitor the scan tool for at least two minutes.
With the scan tool, select View DTCs.

Is the status Active for this DTC?

Yes


No

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



Turn the ignition off.
Disconnect the TIPM C1 harness connector.
Disconnect the ECM harness connectors.
Remove the ASD Relay from the TIPM.
Connect a jumper wire between cavity 30 and cavity 87 of the ASD Relay Connector.
Turn the ignition on.
Measure the voltage of the (C13) A/C Clutch Control circuit in the TIPM harness connector.

Is there any voltage present?

Yes


No

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



Turn the ignition off.
Remove the jumper wire and install the ASD Relay.
Measure the resistance of the (C13) A/C Clutch Control circuit between the TIPM harness connector and the ECM harness connector.

Is the resistance below 10.0 ohms?

Yes


No