P0645-A/C CLUTCH RELAY CIRCUIT
P0645-A/C CLUTCH RELAY CIRCUIT
For a complete wiring diagram, refer to the Wiring Information.
Theory of operation
When the ignition switch is on, the Totally Integrated Power Module (TIPM) sends a 12 Volt signal to the Powertrain Control Module (PCM) on the A/C Clutch Relay Control circuit. The PCM grounds this signal to indicate a request for A/C Compressor Clutch operation.
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When Monitored:
With the ignition on. Battery voltage greater than 10.0 Volts. A/C is being requested.
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Set Condition:
An open or shorted condition is detected in the A/C Clutch Relay control circuit. One Trip Fault. Three good trips to turn off the MIL.
Possible Causes |
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| (C13) A/C CLUTCH RELAY CONTROL CIRCUIT OPEN |
| (C13) A/C CLUTCH RELAY CONTROL CIRCUIT SHORTED TO GROUND |
| TOTALLY INTEGRATED POWER MODULE (TIPM) |
| POWERTRAIN CONTROL MODULE (PCM) |
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
| NOTE: | If there are any ASD/Main Relay or system voltage DTCs present, diagnose those DTCs before proceeding with this test procedure. |
| 1. | Ignition on, engine not running. |
| 2. | With the scan tool, select View DTCs. Copy DTC and Freeze Frame information and clear DTCs. |
| NOTE: | Active or pending DTCs may not allow A/C clutch actuation, make sure all DTCs are cleared before proceeding with this test procedure. |
| 3. | With the scan tool, actuate the A/C Compressor. |
| 4. | Monitor the scan tool for at least two minutes. |
| 5. | With the scan tool, select View DTCs. |
Is the status Active for this DTC?
Yes
- Go To 2
No
- Perform the INTERMITTENT CONDITION diagnostic procedure. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
2. (C13) A/C CLUTCH RELAY CONTROL CIRCUIT SHORTED TO GROUND
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| 1. | Turn the ignition off. |
| 2. | Disconnect the TIPM C5 harness connector. |
| 3. | Disconnect the PCM C1 harness connector. |
| 4. | Measure the resistance between ground and the (C13) A/C Clutch Relay Control circuit in the PCM C1 harness connector. |
Is the resistance below 1000 Ohms?
Yes
- Repair the short to ground in the (C13) A/C Clutch Relay Control circuit.
- Perform the POWERTRAIN VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
No
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Go To 3
3. (C13) A/C CLUTCH CONTROL CIRCUIT OPEN OR HIGH RESISTANCE
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| 1. | Measure the resistance of the (C13) A/C Clutch Control circuit between the TIPM C5 harness connector and the PCM C1 harness connector. |
Is the resistance below 5.0 Ohms?
Yes
- Go To 4
No
- Repair the open or high resistance in the (C13) A/C Clutch Control circuit.
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Perform the POWERTRAIN VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM)
- Standard Procedure)
4. TOTALLY INTEGRATED POWER MODULE (TIPM) ACTUATION
| 1. | Reconnect the TIPM C1 harness connector. |
| 2. | Turn the ignition on. |
| 3. | Connect a jumper between ground and the (C13) A/C Clutch Relay Control circuit at the PCM C1 harness connector. |
| NOTE: | The A/C Compressor Clutch should engage when the (C13) A/C Clutch Relay Control circuit is jumped to ground. |
Did the A/C Compressor Clutch engage when the (C13) A/C Clutch Relay Control circuit is jumped to ground?
Yes
- Go To 6
No
- Go To 5
5. TOTALLY INTEGRATED POWER MODULE (TIPM)
| 1. | Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Totally Integrated Power Module (TIPM) and the Powertrain Control Module (PCM). |
| 2. | Look for any chafed, pierced, pinched or partially broken wires. |
| 3. | Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related connectors. |
| 4. | Perform any Technical Service Bulletins that may apply. |
Were any problems found?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
No
- Replace and program the Totally Integrated Power Module (TIPM) in accordance with the Service Information. (Refer to 08 - Electrical/8E - Electronic Control Modules/MODULE, Totally Integrated Power (TIPM) - Removal).
- Perform the BODY VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Totally Integrated Power (TIPM) - Standard Procedure).
6. POWERTRAIN CONTROL MODULE (PCM)
| 1. | Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Totally Integrated Power Module (TIPM) and the Powertrain Control Module (PCM). |
| 2. | Look for any chafed, pierced, pinched or partially broken wires. |
| 3. | Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related connectors. |
| 4. | Perform any Technical Service Bulletins that may apply. |
Were any problems found?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
No
- Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information. (Refer to 08 - Electrical/8E - Electronic Control Modules/MODULE, Powertrain Control - Removal) .
- Perform the POWERTRAIN VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).