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Test Description

WARNING: This page is about a different car, the 2007 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.

The number below refers to the step number on the diagnostic table.

  1. 12:  Check the connection by removing and securely reinstalling before replacement of the HVAC control is considered.
HVAC Compressor Clutch Does Not Disengage (Non-Hybrid)

Step Action Values Yes No
Schematic Reference: HVAC Schematics 
Connector End View Reference: HVAC Connector End Views 
DEFINITION: The A/C compressor clutch will not disengage when an A/C request has not been made and a powertrain DTC has not been set.
1 Did you perform the Diagnostic System Check - Vehicle? - Go to Step 2  Go to Diagnostic System Check - Vehicle
2
  1. Start the engine.
  2. Place the blower motor switch in the OFF position.
  3. Place the A/C request switch in the OFF position.
Does the A/C compressor operate?
- Go to Step 3  Go to Testing for Intermittent Conditions and Poor Connections
3 With a scan tool, observe the A/C Request Signal parameter in the engine control module (ECM) or powertrain control module (PCM), General Info Inputs data list.
Does the scan tool indicate that the A/C Request Signal parameter is YES?
- Go to Step 4  Go to Step 6 
4 Test the A/C request signal circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?
- Go to Step 18  Go to Step 5 
5
  1. Turn OFF the ignition.
  2. Disconnect the A/C Refrigerant pressure sensor.
  3. Start the engine.
  4. With a scan tool, observe the A/C Request Signal parameter.
Does the scan tool indicate that the A/C Request Signal parameter is YES?
- Go to Step 13  Go to Step 12 
6 With a scan tool, command the A/C compressor clutch relay ON and OFF.
Does the A/C compressor clutch relay turn ON and OFF with each command?
- Go to Step 7  Go to Step 9 
7 Remove the A/C compressor clutch relay.
Is the A/C compressor ON?
- Go to Step 10  Go to Step 8 
8 Measure the resistance between the switch side A/C compressor clutch relay terminals.
Does the resistance measurement equal the specified value?
Go to Step 9  Go to Step 11 
9 Test the A/C clutch relay control circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?
- Go to Step 18  Go to Step 13 
10 Test the A/C compressor clutch supply voltage circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?
- Go to Step 18  Go to Step 15 
11 Inspect for poor connections at the A/C compressor clutch relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .
Did you find and correct the condition?
- Go to Step 18  Go to Step 14 
12  Inspect for poor connections at the harness connector of the HVAC control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .
Did you find and correct the condition?
- Go to Step 18  Go to Step 16 
13 Inspect for poor connections at the harness connector of the ECM/PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .
Did you find and correct the condition?
- Go to Step 18  Go to Step 17 
14 Replace the A/C compressor clutch relay.
Did you complete the replacement?
- Go to Step 18  -
15 Replace the A/C compressor clutch. Refer to Compressor Clutch Assembly Replacement (L61/L66) .
Did you complete the replacement?
- Go to Step 18  -
16 Replace the HVAC control module. Refer to Control Module References for replacement, setup, and programming.
Did you complete the replacement?
- Go to Step 18  -
17 Replace the ECM/PCM. Refer to Control Module References for replacement, setup, and programming.
Did you complete the replacement?
- Go to Step 18  -
18 Operate the system in order to verify the repair.
Did you correct the condition?
- System OK Go to Step 3