For 1990-2009 cars

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
DEFINITION: A/C compressor clutch will not disengage when no A/C request has been made and no Powertrain DTC has been set.
1 | Were you sent here from the HVAC System Check? | -- | Go to Step 2 | Go to HVAC System Check
2 |

1. Disconnect the Powertrain Control Module (PCM) connector C2.
2. Turn the ignition switch to the ON position.

Does the A/C clutch disengage?

--

Go to Step 3

Go to Step 4

3 | Replace the Powertrain Control Module (PCM). Refer to Powertrain Control Module Replacement/Programming in Engine Controls. Is the repair complete? | -- | Go to HVAC System Check | --
4 |

1. Disconnect the A/C CLU Micro relay #13 from the underhood electrical center.
2. Turn the ignition switch to the ON position.

Does the A/C clutch disengage?

--

Go to Step 5

Go to Step 8

5 |

1. Turn the ignition switch to the OFF position.
2. Powertrain Control Module (PCM) connector C2 still disconnected.
3. A/C CLU Micro relay #13 still removed from the underhood electrical center.
4. Connect a J 39200 between the Powertrain Control Module (PCM) connector C2 terminal 39 and ground.
5. Measure for continuity in CKT 459 to ground.

Is CKT 459 continuous to ground?

--

Go to Step 6

Go to Step 7

6 | Locate and repair a short to ground in CKT 459 between the underhood electrical center and the PCM connector C1. Is the repair complete? | -- | Go to HVAC System Check | --
7 | Replace the A/C CLU micro relay #13. Is the repair complete? | -- | Go to HVAC System Check | --
8 |

1. Powertrain Control Module (PCM) connector C2 still disconnected.
2. A/C CLU Micro relay #13 still removed from the underhood electrical center.
3. Disconnect the A/C compressor clutch connector.
4. Connect a J 39200 between the A/C compressor clutch connector connector (CKT 59) and ground.
5. Turn the ignition switch to the ON position.
6. Measure for voltage on CKT 59.

Is voltage present on CKT 59?

--

Go to Step 9

Go to Step 10

9 | Locate and repair a short to battery voltage on CKT 59 between the underhood electrical center and the A/C compressor clutch. Is the repair complete? | -- | Go to HVAC System Check | --
10 | Replace the A/C compressor clutch. Refer to Compressor Clutch Plate/Hub Assembly Replacement . Is the repair complete? | -- | Go to HVAC System Check | --