P0647
P0647-HIGH VOLTAGE DETECTED AT THE A/C CLUTCH OUTPUT
For complete wiring diagrams refer to Diagrams/Electrical.
- When Monitored:
When the ignition is on.
- Set Condition:
When the signal from the A/C Clutch output does not match the signal from the A/C Clutch feedback.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.
Diagnostic Test
1. A/C CLUTCH CIRCUIT SHORTED TO EXTERNAL VOLTAGE
Ignition off.
Disconnect the ECM and TIPM connectors.
NOTE: Check connectors - Clean/repair as necessary.
Ignition on, engine not running.
Using a Voltmeter, measure the voltage of the A/C Clutch Control Circuit between the TIPM connector and battery negative.
Is the voltage less than 1 volt?
Yes
- Go To 2
Yes
- Repair or Replace the wiring harness.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
2. ECM
Ignition off.
Connect the ECM and TIPM connectors.
Ignition on, engine not running.
Using a back probing tool 6801, back probe the A/C clutch control circuit in the TIPM connector.
Using a 12-volt test light connected to battery positive, check the transmission control circuit at the TIPM connector while actuating the A/C clutch circuit with the Electronic Service Tool.
NOTE: The test light must illuminate brightly.
Compare the brightness to that of a direct connection to the battery.
Does the test light illuminate brightly?
Yes
- Go To 3
No
- Replace the ECM.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
3. TIPM
Using a back probing tool 6801, back probe the A/C clutch power circuit in the TIPM connector.
Using a 12-volt test light connected to battery positive, check the transmission power circuit at the TIPM connector while actuating the A/C clutch circuit with the Electronic Service Tool.
NOTE: The test light must illuminate brightly.
Compare the brightness to that of a direct connection to the battery.
Does the test light illuminate brightly?
Yes
- Test complete.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
No
- Replace the TIPM.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test