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Test F: Compressor Clutch Does Not Disengage

WARNING: This page is about a different car, the 2002 Oldsmobile Intrigue. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: For circuit reference, 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-DIAGNOSTICS. 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, test wiring systems for intermittent and poor connections.
  3. Using a scan tool, observe A/C REQUEST SIGNAL parameter in PCM data list. If scan tool indicates A/C Request Signal parameter is ON, go to next step. If scan tool does not indicate A/C Request Signal parameter is ON, go to step  6.
  4. Test Dark Green/White wire between PCM connector C2, terminal No. 22 and HVAC control module terminal A3 connector C2 for a short to ground. If a short to ground is found, repair as necessary. When repair is complete, go to step  17. If wire is okay, go to next step.
  5. Turn ignition off. Back out HVAC control module terminal A3 in connector C2 from HVAC control head. Start engine. Using a scan tool, observe A/C REQUEST SIGNAL parameter. If scan tool indicates A/C Request Signal parameter is ON, go to step 12. If scan tool does not indicate A/C Request Signal parameter is ON, go to step  11.
  6. Remove A/C compressor clutch relay. If A/C compressor clutch turns off, go to next step. If A/C compressor clutch does not turn off, go to step  9.
  7. Using a DVOM, measure resistance between switch side A/C compressor clutch relay terminals. If resistance measurement is infinity, go to next step. If resistance measurement is not infinity, go to step  10.
  8. Test A/C clutch relay control circuit (no wire color available) for a short to ground. If a short to ground is found, repair as necessary. When repair is complete, go to step  17. If circuit is okay, go to step  12.
  9. Test A/C compressor clutch supply voltage circuit (no wire color available) for a short to voltage. If a short to voltage is found, repair as necessary. When repair is complete, go to step  17. If circuit is okay, go to step  14.
  10. Check for poor connections at A/C compressor clutch relay. If poor connection is found, repair as necessary. When repair is complete, go to step  17. If connector is okay, go to step  13.
  11. Check HVAC control module harness connector for poor connections. If poor connection is found, repair as necessary. When repair is complete, go to step  17. If connector is okay, go to step  15.
  12. Check harness connector of PCM for poor connections. If poor connection is found, repair as necessary. When repair is complete, go to step  17. If connector is okay, go to step  16.
  13. Replace A/C compressor clutch relay. See COMPRESSOR RELAY  under REMOVAL & INSTALLATION. After repair, go to step  17.
  14. Replace A/C compressor clutch. See appropriate COMPRESSOR SERVICING article in GENERAL SERVICING. After repair, go to step  17.
  15. Replace HVAC control assembly. See HVAC CONTROL ASSEMBLY  under REMOVAL & INSTALLATION. After repair, go to step  17.
  16. Replace and reprogram PCM. See POWERTRAIN CONTROL MODULE under COMPUTERIZED ENGINE CONTROLS in REMOVAL, OVERHAUL & INSTALLATION article in ENGINE PERFORMANCE. When repairs are complete, go to next step.
  17. Operate system to verify repair. If system operates normally, repair is complete. If system still malfunctions, go to step  3.
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