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A/C Compressor Inoperative

  1. Turn ignition on. Locate test connector within the Engine Control Module (ECM) housing. Connect a test light between ground and terminal No. 3 (Brown wire) of test connector. If test light comes on, go to step 3). If test light does not come on, go to next step.
  2. Repair open circuit or high resistance in Brown wire between A/C compressor relay and fuse block. After repairing wire, go to next step.
  3. Disconnect A/C compressor relay (K60). Connect a test light between ground and Red wire terminal of A/C compressor relay harness connector. If test light comes on, go to step 5). If test light does not comes on, go to next step.
  4. Repair open circuit or high resistance in Red wire between A/C compressor relay and fuse block. After repairing wire, go to next step.
  5. Using a DVOM, check continuity of Green wire and Brown/Black wire between A/C compressor diode and A/C compressor clutch coil. If continuity exists, go to step 7). If no continuity exists, go to next step.
  6. Repair open circuit or high resistance in Green wire or Brown/Black wire between A/C compressor diode and A/C compressor clutch coil. After repairing wire(s), go to next step.
  7. Turn ignition off. Connect a fused jumper between terminal No. 4 (Green wire) and terminal No. 8 (Red wire) of A/C compressor relay wiring harness connector. Disconnect temperature switch No. 2. Connect a fused jumper wire between ground and Brown/Black wire terminal of temperature switch No. 2 wiring harness connector. If A/C compressor operates, go to step 9). If A/C compressor does not operate, go to next step.
  8. Check for open circuit or high resistance in Green wire or Brown/Black wire to A/C compressor clutch. If wires are okay, replace A/C compressor clutch coil. After repairing wire(s) or replacing clutch, go to next step.
  9. Turn ignition off. Connect a fused jumper wire between Brown/Black wire terminal and Black wire terminal of temperature switch No. 2 wiring harness connector. Turn ignition on. If A/C compressor operates, go to step 11). If A/C compressor does not operate, go to next step.
  10. Replace temperature switch No. 2 and go to step 12).
  11. Repair open circuit or high resistance in Black (ground) wire to temperature switch No. 2. If repair is completed, go to step 13). If repair is not complete, go to next step.
  12. Turn ignition off. Remove both fused jumper wires. Connect a fused jumper wire between ground and terminal No. 6 (Brown/Purple wire) of A/C compressor relay (K60). Turn ignition on. If A/C compressor operates, go to step 14). If A/C compressor does not operate, go to next step.
  13. Replace A/C compressor relay. After replacing relay, go to next step.
  14. Turn ignition off. Remove fused jumper between ground and A/C compressor relay. Disconnect A/C compressor refrigerant pressure switch. Measure resistance between terminal No. 1 and 2 (Black/White wires) of refrigerant pressure switch. If resistance is less than 2 ohms, go to next step. If resistance is not as specified, go to step 16).
  15. Replace A/C compressor refrigerant pressure switch. After replacing switch, go to next step.
  16. Check continuity of Black/White wire between A/C-heater control panel and Engine Control Module (ECM). Also check continuity of Brown/Purple wire between A/C compressor relay and ECM. If continuity of wires is okay, go to next step. If continuity of wire(s) is not okay, go to step 18).
  17. Repair open circuit or high resistance in Black/White wire or Brown/Purple wire to ECM. After repairing wire(s), go to next step.
  18. Disconnect ECM connector. Connect a fused jumper wire between terminal No. 15 (Black/White wire) and terminal No. 36 (Brown/Purple wire) of ECM wiring harness connector. Turn ignition on. Press A/C button on A/C-heater control panel. If A/C compressor does not operate, go to next step. If A/C compressor operates, reconnect wiring and components. Verify A/C compressor operates properly.
  19. Replace A/C-heater control panel. After replacing A/C-heater control panel, reconnect wiring and components. Verify A/C compressor operates properly.
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