[55B] AUTOMATIC AIR CONDITIONER - - TROUBLESHOOTING - SYMPTOM PROCEDURES - INSPECTION PROCEDURE 2: The air conditioner does not work at all.PRINT PAGE / INDEX / PRIOR / NEXT
INSPECTION PROCEDURE 2: The air conditioner does not work at all.
CIRCUIT OPERATION
If cool air is not distributed when the A/C switch is on, A/C compressor relay system may be defective.
POSSIBLE CAUSES
  • Improper amount of refrigerant
  • Malfunction of the A/C pressure sensor
  • Malfunction of the A/C compressor relay
  • Malfunction of the magnetic clutch
  • Malfunction of the A/C refrigerant temperature switch
  • Damaged the wiring harness or connectors
  • Malfunction of the automatic air conditioner control panel (A/C-ECU)
DIAGNOSIS
Step 1. Use the MUT-II/III to confirm a diagnosis code.
On completion, check that the diagnosis code is not reset.
Q: Is the check result normal?
YES:  Go to Step 2.
NO:  Refer to diagnosis code chart .
Step 2. Check the blower operation.
  1. Turn the ignition switch to the ON position.
  1. Blower knob: Other than OFF
  1. Check that the air comes out of the blower.
Q: Is the check result normal?
YES:  Go to Step 3.
NO:  Refer to Inspection Procedure 5 "The blower motor air volume be changed ."
Step 3. Check the rear window defogger and outside/inside air selection damper control motor operation.
Q: Do the rear window defogger and outside/inside air selection damper control motor work normally?
YES:  Go to Step 4.
NO:  Refer to Inspection procedure 10 "Malfunction of the A/C-ECU power supply system ."
Step 4. Check the A/C compressor.
Check the A/C compressor for compressor oil leaks.
Q: Is the check result satisfactory?
YES:  Go to Step 5.
NO:  Replace the A/C compressor or the expansion valve.
Step 5. Measure the voltage at A/C compressor connector B-27.
  1. Disconnect A/C compressor connector B-27 and measure the voltage at the relay box side.
  1. Turn the ignition switch to the "ON" position.
  1. Disconnect engine-A/T-ECU connector C-112, and earth terminal 21. <2000, 2000 DOHC>
  1. Disconnect engine-A/T-ECU connector C-134, and earth terminal 16. <2400, 2400-MIVEC>
  1. Measure the voltage between terminal 1 and earth.
    2. OK: System voltage
Q: Is the check result normal?
YES:  Go to Step 19.
NO:  Go to Step 6.
Step 6. Check the A/C compressor relay continuity.
Refer to GROUP 55A, On vehicle service - power relay .
Q: Is the A/C compressor relay in good condition?
YES:  Go to Step 7.
NO:  Replace the A/C compressor relay.
Step 7. Measure the voltage at A/C compressor relay connector B-18X.
  1. Disconnect A/C compressor connector B-18X and measure the voltage at the relay box side.
  1. Turn the ignition switch to the "ON" position.
  1. Measure the voltage between terminal 3 and earth.
    2. OK: System voltage
Q: Is the check result normal?
YES:  Go to Step 10.
NO:  Go to Step 8.
Step 8. Connector check: A/C compressor relay connector B-18X.
Q: Is the check result normal?
YES:  Go to Step 9.
NO:  Repair the connector.
Step 9. Check the wiring harness between A/C compressor relay connector B-18X (terminal 3) and the ignition switch (IG2).
NOTE: Prior to the wiring harness inspection, check junction block connectors C-203, C-202 and intermediate connector C-106, and repair if necessary.
Q: Is the check result normal?
YES:  The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
NO:  Repair the wiring harness.
Step 10. Measure the voltage at A/C compressor relay connector B-18X.
  1. Disconnect A/C compressor connector B-18X and measure the voltage at the wiring harness side.
  1. Measure the voltage between terminal 4 and earth.
    2. OK: System voltage
Q: Is the check result normal?
YES:  Go to Step 13.
NO:  Go to Step 11.
Step 11. Connector check: A/C compressor relay connector B-18X
Q: Is the check result normal?
YES:  Go to Step 12.
NO:  Repair the connector.
Step 12. Check the wiring harness between A/C compressor relay connector B-18X (terminal 4) and the battery.
NOTE: Prior to the wiring harness inspection, check intermediate connector A-14, and repair if necessary.
Q: Is the check result normal?
YES:  Check that the air conditioner works normally.
NO:  Repair the wiring harness. Check that the air conditioner works normally.
Step 13. Connector check: A/C compressor relay connector B-18X and A/C compressor connector B-27
Q: Is the check result normal?
YES:  Go to Step 14.
NO:  Repair or replace the connector.
Step 14. Check the wiring harness between A/C compressor relay connector B-18X (terminal 1) and A/C compressor connector B-27 (terminal 1).
Q: Is the check result normal?
YES <2000>:  Go to Step 15.
YES <2400>:  Go to Step 17.
NO:  Repair the wiring harness.
Step 15. Connector check: engine-A/T-ECU connector C-112 and A/C compressor relay connector B-18X
Q: Is the check result normal?
YES:  Go to Step 16.
NO:  Repair the connector.
Step 16. Check the wiring harness between engine-A/T-ECU connector C-112 (terminal 21) and A/C compressor relay connector B-18X (terminal 2).
Q: Is the check result normal?
YES:  The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
NO:  Repair the wiring harness.
Step 17. Connector check: engine-A/T-ECU connector C-134 and A/C compressor relay connector B-18X
Q: Is the check result normal?
YES:  Go to Step 18.
NO:  Repair the connector.
Step 18. Check the wiring harness between engine-A/T-ECU connector C-134 (terminal 16) and A/C compressor relay connector B-18X (terminal 2).
Q: Is the check result normal?
YES:  The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
NO:  Repair the wiring harness.
Step 19. Measure the voltage at A/C-ECU connector C-26.
  1. Disconnect A/C compressor connector C-06 and measure the voltage at the relay box side.
  1. Turn the ignition switch to the "ON" position.
  1. Disconnect engine-A/T-ECU connector C-112, and earth terminal 21.
  1. Measure the voltage between terminal 33 and earth.
    2. OK: System voltage
Q: Is the check result normal?
YES:  Go to Step 22.
NO:  Go to Step 20.
Step 20. Connector check: A/C compressor relay connector B-18X and A/C-ECU connector C-26
Q: Is the check result normal?
YES:  Go to Step 21.
NO:  Repair or replace the connector.
Step 21. Check the wiring harness between A/C compressor relay connector B-18X (terminal 1) and A/C-ECU connector C-26 (terminal 33).
NOTE: Prior to the wiring harness inspection, check intermediate connector C-104, and repair if necessary.
Q: Is the check result normal?
YES:  The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
NO:  Repair the wiring harness.
Step 22. Check the magnetic clutch operation.
Refer to .
Q: Is the check result normal?
YES:  Go to Step 23.
NO:  Replace the compressor magnet clutch.
Step 23. Check the refrigerant temperature switch.
Refer to .
Q: Is the check result normal?
YES:  Go to Step 24.
NO:  Replace the refrigerant temperature switch.
Step 24. Check the refrigerant level.
Refer to .
Q: Is the refrigerant level correct?
YES:  Go to Step 25.
NO:  Correct the refrigerant level (Refer to On-vehicle Service ).
Step 25. Check the A/C pressure sensor operation.
Refer to .
Q: Is the A/C pressure sensor operating properly?
YES:  Go to Step 26.
NO:  Replace the A/C pressure sensor.
Step 26. Connector check: A/C pressure sensor connector A-02 and A/C-ECU connector C-27
Q: Is the check result normal?
YES:  Go to Step 27.
NO:  Repair the connector.
Step 27. Check the wiring harness between A/C pressure sensor connector A-02 (terminal 2) and A/C-ECU connector C-27 (terminal 11).
NOTE: Prior to the wiring harness inspection, check intermediate connector C-116, and repair if necessary.
Q: Is the check result normal?
YES <2000>:  Go to Step 28.
YES <2400>:  Go to Step 30.
NO:  Repair the wiring harness.
Step 28. Connector check: engine-A/T-ECU connector C-111, C-110 and A/C-ECU connector C-26
Q: Is the check result normal?
YES:  Go to Step 29.
NO:  Repair or replace the connector.
Step 29. Check the wiring harness between engine-A/T-ECU connectors C-111 (terminal 64), C-110 (terminal 83) and A/C-ECU connector C-26 (terminals 32 and 34).
NOTE: Prior to the wiring harness inspection, check intermediate connector C-104, and repair if necessary.
Q: Is the check result normal?
YES:  Replace the A/C-ECU or engine-A/T-ECU.
NO:  Repair the wiring harness.
Step 30. Connector check: engine-A/T-ECU connector C-136 and A/C-ECU connector C-26
Q: Is the check result normal?
YES:  Go to Step 31.
NO:  Repair or replace the connector.
Step 31. Check the wiring harness between engine-A/T-ECU connectors C-136 (terminal 78 and 69) and A/C-ECU connector C-26 (terminals 32 and 34).
NOTE: Prior to the wiring harness inspection, check intermediate connector C-104, and repair if necessary.
Q: Is the check result normal?
YES:  Replace the A/C-ECU or engine-A/T-ECU.
NO:  Repair the wiring harness.
[55B] AUTOMATIC AIR CONDITIONER - - TROUBLESHOOTING - SYMPTOM PROCEDURES - INSPECTION PROCEDURE 2: The air conditioner does not work at all.PRINT PAGE / INDEX / PRIOR / NEXT
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