SCHEMATIC REFERENCE:

Compressor Control W/CJ2

Did you perform the HVAC Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check

1. Install a scan tool.
2. Turn ON the ignition, with the engine OFF.
3. With a scan tool, command the A/C Relay ON and OFF.

Does the A/C clutch engage and disengage with each command?

Go to Step 3

Go to Step 4

IMPORTANT: Indicated outside air temperature must be above 7°C (45°F).

1. Start the engine.
2. Adjust driver side temperature to 16°C (60°F).
3. Ensure the VENT mode indicator is not illuminated.
4. With a scan tool, observe the Commanded A/C parameter in the PCM Engine Data 2 list.

Does the scan tool display ON?

Go to Step 20

Go to Step 11

1. Turn OFF the ignition.
2. Disconnect the A/C relay.
3. Probe the switched input circuit of the A/C relay with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 5

Go to Step 6

Connect a test lamp between the switched input circuit of the A/C relay and the switched output circuit of the A/C relay.

Does the test lamp illuminate?

Go to Step 16

Go to Step 7

Repair the switched input circuit of the A/C relay. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 25

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1. Disconnect the A/C compressor clutch.
2. Connect the A/C relay.
3. Turn ON the ignition, with the engine OFF.
4. Connect a test lamp between the input circuit of the A/C compressor clutch and the ground circuit of the A/C compressor clutch.
5. With a scan tool, command the A/C Relay ON.

Does the test lamp illuminate?

Go to Step 17

Go to Step 8

1. Turn OFF the ignition.
2. Connect a test lamp between battery positive voltage and the ground circuit of the A/C compressor clutch.

Does the test lamp illuminate?

Go to Step 9

Go to Step 10

Repair the input circuit of the A/C compressor clutch. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 25

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Repair the ground circuit of the A/C compressor clutch. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 25

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With a scan tool, observe the Control Head (Desired) parameter in the DIM A/C Information list.

Does the scan tool display A/C ON?

Go to Step 12

Go to Step 15

With a scan tool, observe the A/C Clutch (Desired) parameter in the DIM A/C Information list.

Does the scan tool display ON?

Go to Powertrain On Board Diagnostic (OBD) System Check in Engine Controls-3.8L

Go to Step 13

With a scan tool, observe the Clutch Voltage parameter in the DIM A/C Information list.

Does the scan tool display Normal?

Go to Step 14

Go to Diagnostic System Check - Engine Electrical in Engine Electrical

With a scan tool, observe the Pressure Status parameter in the DIM A/C Information list.

Does the scan tool display Normal?

Go to Step 19

Go to System Performance Test

With a scan tool, observe the A/C Requested parameter in the IPM HVAC System Data list.

Does the scan tool display Yes?

Go to Step 19

Go to Step 18

Replace the A/C relay.

Did you complete the replacement?

Go to Step 25

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Inspect for poor connections at the harness connector of the A/C compressor clutch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 25

Go to Step 21

Inspect for poor connections at the harness connector of the instrument panel module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 25

Go to Step 22

Inspect for poor connections at the harness connector of the dash integration module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 25

Go to Step 23

Inspect for poor connections at the harness connector of the powertrain control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 25

Go to Step 24

Replace the A/C compressor clutch. Refer to Compressor Clutch Coil Removal (V5 - Conventional Mount) .

Did you complete the replacement?

Go to Step 25

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Replace the instrument panel module. Refer to Instrument Panel Module Replacement in Body Control System.

Did you complete the replacement?

Go to Step 25

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Replace the dash integration module. Refer to Dash Integration Module Replacement in Body Control System.

Did you complete the replacement?

Go to Step 25

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Replace the powertrain control module. Refer to Powertrain Control Module Replacement/Programming in Engine Controls-3.8L.

Did you complete the replacement?

Go to Step 25

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Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2