DEFINITION: A/C compressor clutch will not disengage when no A/C request has been made and no Powertrain DTC has been set.

SCHEMATIC REFERENCE: HVAC Compressor Control Schematics

Did you review the HVAC operation and perform the necessary inspections?

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Go to Step 2

Go to Symptoms

Important:: Verify that ambient temperature is above 7° C (44° F) before testing.

1. Start engine.
2. Turn the mode switch to either Off, Vent or Heat.

Does the system operate normally?

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Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

1. Park the vehicle inside or in the shade.
2. Open the windows in order to ventilate the interior of the vehicle.
3. If the A/C system was operating, allow the A/C system to equalize (about 2 minutes).
4. Ensure that the ignition key is in the OFF position.
5. Install the J 39500-B .
6. Record the ambient temperature at the vehicle.
7. Record readings of the low and high side STATIC pressures.

Are both the low and high side pressures within 103 kPa (15 psi) of the ambient pressure?

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Go to Step 4

Go to Leak Testing in Heating, Ventilation and Air Conditioning

1. Disconnect the Vehicle Control Module (VCM) connector.
2. Turn ON the ignition, with the engine OFF.

Does the A/C compressor clutch coil disengage?

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Go to Step 5

Go to Step 6

Probe the A/C request signal circuit with a test light that is connected to a good ground.

Does the test lamp illuminate?

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Go to Step 13

Go to Step 15

1. Turn OFF the ignition.
2. Disconnect the A/C enable relay.
3. Turn ON the ignition, with the engine OFF.

Does the A/C compressor clutch coil disengage?

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Go to Step 7

Go to Step 10

1. Turn OFF the ignition.
2. Connect a DMM between the A/C clutch relay control circuit at the VCM to a good ground.

Does the DMM show continuity?

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Go to Step 8

Go to Step 9

Repair the A/C clutch relay control circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

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Go to Step 13

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Replace the A/C enable relay.

Did you complete the replacement?

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Go to Step 13

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1. Turn OFF the ignition.
2. Disconnect the A/C compressor clutch coil connector.
3. Connect a DMM between the A/C compressor clutch supply circuit at the compressor to a good ground.
4. Turn ON the ignition, with the engine OFF.

Does the voltage measure near the specified value?

B+

Go to Step 11

Go to Step 12

Repair the A/C compressor clutch supply voltage circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

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Go to Step 17

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Replace the A/C compressor clutch. Refer to Compressor Clutch Plate/Hub Assembly Replacement in Heating, Ventilation and Air Conditioning.

Did you complete the replacement?

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Go to Step 17

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1. Disconnect the heater and A/C control module.
2. Probe the A/C request signal circuit at the VCM with a test light that is connected to a good ground.

Does the test lamp illuminate?

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Go to Step 14

Go to Step 16

Repair the A/C request signal circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

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Go to Step 17

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Important:: Perform the reprogramming procedure for the PCM.

Replace the Vehicle Control Module (VCM). Refer to in Engine Controls.

Did you complete the replacement?

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Go to Step 17

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Replace the heater and A/C control module. Refer to Control Assembly Replacement in Heating, Ventilation and Air Conditioning.

Did you complete the replacement?

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Go to Step 17

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Operate the system in order to verify the repair.

Did you correct the condition?

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System OK

Go to Step 3