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Test F: Compressor Clutch Does Not Disengage

WARNING: This page is about a different car, the 2002 Chevrolet Malibu. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: For correct circuit identification and connector terminal locations, see CONNECTOR IDENTIFICATION  and/or WIRING DIAGRAMS .
NOTE: 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. Perform DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. Go to next step.
  2. Start engine. Place blower motor switch in OFF position. Place A/C request switch in OFF position. If A/C compressor operates, go to next step. If A/C compressor does not operate, problem is intermittent. Check wiring and connections.
  3. Using scan tool, observe A/C REQUEST parameter in POWERTRAIN DATA LIST 2. If scan tool indicates A/C Request parameter is OFF, go to next step. If scan tool indicates A/C Request parameter is ON, go to step  6.
  4. Using scan tool, observe A/C RELAY COMMANDED parameter in BODY CONTROL MODULE DATA LIST 2. If scan tool indicates A/C RELAY COMMANDED parameter is OFF, go to next step. If scan tool indicates A/C RELAY COMMANDED parameter is ON, go to step  14.
  5. Test A/C compressor clutch relay control circuit for a short to ground. Repair as necessary, then go to step  20. If circuit is okay, go to step  7.
  6. Start engine. Place A/C switch in OFF position. Measure voltage between A/C request circuit at Body Control Module (BCM) and ground. If voltage measures near 12 volts, go to step  9. If voltage does not measure near 12 volts, go to step  13.
  7. Remove A/C compressor clutch relay. If A/C compressor clutch turns off, go to step  10. If A/C compressor clutch does not turn off, go to next step.
  8. Test A/C compressor clutch voltage supply circuit, at A/C compressor clutch for a short to voltage. Repair as necessary, then go to step  20. If circuit is okay, go to step  11.
  9. Test A/C request signal circuit for a short to voltage. Repair as necessary, then go to step  20. If circuit is okay, go to step  12.
  10. Inspect for poor connections at A/C compressor clutch relay. Repair as necessary, then go to step  20. If connections are okay, go to step  15.
  11. Inspect for poor connections at A/C compressor clutch harness connector. Repair as necessary, then go to step  20. If connections are okay, go to step  16.
  12. Inspect for poor connections at HVAC control assembly harness connector. Repair as necessary, then go to step  20. If connections are okay, go to step  17.
  13. Inspect for poor connections at BCM. Repair as necessary, then go to step  20. If connections are okay, go to step  18.
  14. Inspect for poor connections at PCM harness connector. Repair as necessary, then go to step  20. If connections are okay, go to step  19.
  15. Replace A/C compressor clutch relay. See COMPRESSOR CLUTCH RELAY  under REMOVAL & INSTALLATION. After replacement, go to step  20.
  16. Replace A/C compressor clutch. See COMPRESSOR SERVICING in GENERAL SERVICING article in GENERAL SERVICING. After replacement, go to step  20.
  17. Replace HVAC control assembly. See HVAC CONTROL ASSEMBLY  under REMOVAL & INSTALLATION. After repairs are complete, go to step  20.
  18. Replace BCM. See appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT. After replacement, go to step  20.
  19. Replace and reprogram PCM. See POWERTRAIN CONTROL MODULE in REMOVAL, OVERHAUL & INSTALLATION article in ENGINE PERFORMANCE. After replacement, go to next step.
  20. Operate system to verify repair. If system operates properly, system is okay. If system does not operate properly, go to step  2.
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