[55A] HEATER, AIR CONDITIONER AND VENTILATION - - TROUBLESHOOTING - SYMPTOM PROCEDURES - INSPECTION PROCEDURE 3: When the A/C is Operating, Temperature Inside the Passenger Compartment does not Decrease (Cool Air is not Emitted).PRINT PAGE / INDEX / PRIOR / NEXT
INSPECTION PROCEDURE 3: When the A/C is Operating, Temperature Inside the Passenger Compartment does not Decrease (Cool Air is not Emitted).
COMMENTS ON TROUBLE SYMPTOM
If cool air is not distributed when the A/C switch is on, the air thermo sensor or the A/C compressor relay system may be defective.
TROUBLESHOOTING HINTS
  • Improper amount of refrigerant
  • Malfunction of the air thermo sensor
  • Malfunction of the A/C pressure sensor
  • Malfunction of the A/C compressor relay
  • Malfunction of the A/C refrigerant temperature switch
  • Malfunction of the magnetic clutch
  • Malfunction of the manual air conditioner control panel (A/C-ECU)
  • Damaged the wiring harness or connectors
  • Malfunction of the engine-A/T-ECU
DIAGNOSIS
Step 1. 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 2.
NO:  Refer to Inspection procedure 9 "Malfunction of the A/C-ECU power supply system ."
Step 2. Check the blower motor operation.
Q: Does the blower motor work normally?
YES:  Go to Step 3.
NO:  Refer to Inspection procedure 4 "Blower fan and motor do not turn ."
Step 3. Check the A/C compressor.
Check the A/C compressor for compressor oil leaks.
Q: Is the check result satisfactory?
YES:  Go to Step 4.
NO:  Replace the A/C compressor or the expansion valve.
Step 4. Measure the voltage at B-27 A/C compressor connector.
  1. Disconnect B-27 A/C compressor connector and measure the voltage at the relay box side.
  1. Turn the ignition switch to the "ON" position.
  1. Disconnect C-112 engine-A/T-ECU connector, and earth terminal 21. <2400-except MIVEC>
  1. Disconnect C-134 engine-A/T-ECU connector, and earth terminal 16. <2400-MIVEC (except for GCC)>
  1. Disconnect C-134 engine-A/T-ECU connector, and earth terminal 8. <2400-MIVEC (vehicles for GCC)>
  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 5.
Step 5. Check the A/C compressor relay continuity.
Refer to .
Q: Is the check result normal?
YES:  Go to Step 6.
NO:  Replace the A/C compressor relay.
Step 6. Measure the voltage at B-18X A/C compressor relay connector.
  1. Disconnect B-18X A/C compressor connector 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 9.
NO:  Go to Step 7.
Step 7. Connector check: B-18X A/C compressor relay connector
Q: Is the check result normal?
YES:  Go to Step 8.
NO:  Repair or replace the connector.
Step 8. Check the wiring harness between B-18X A/C compressor relay connector (terminal 3) and the ignition switch (IG2).
NOTE: Prior to the wiring harness inspection, check junction block connectors C-203, C-205 <LH drive vehicles>, C-202 <RH drive vehicles> 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 9. Measure the voltage at B-18X A/C compressor relay connector.
  1. Disconnect B-18X A/C compressor connector 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 12.
NO:  Go to Step 10.
Step 10. Connector check: B-18X A/C compressor relay connector
Q: Is the check result normal?
YES:  Go to Step 11.
NO:  Repair or replace the connector.
Step 11. Check the wiring harness between B-18X A/C compressor relay connector (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:  The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
NO:  Repair the wiring harness.
Step 12. Connector check: B-18X A/C compressor relay connector and B-27 A/C compressor connector
Q: Is the check result normal?
YES:  Go to Step 13.
NO:  Repair or replace the connector.
Step 13. Check the wiring harness between B-18X A/C compressor relay connector (terminal 1) and B-27 A/C compressor connector (terminal 1).
Q: Is the check result normal?
YES <2400-except MIVEC>:  Go to Step 14.
YES <2400-MIVEC>:  Go to Step 16.
NO:  Repair the wiring harness.
Step 14. Connector check: C-112 engine-A/T-ECU connector and B-18X A/C compressor relay connector
Q: Is the check result normal?
YES:  Go to Step 15.
NO:  Repair or replace the connector.
Step 15. Check the wiring harness between B-18X A/C compressor relay connector (terminal 2) and C-112 engine-A/T-ECU connector (terminal 21).
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 16. Connector check: C-134 engine-A/T-ECU connector and B-18X A/C compressor relay connector
Q: Is the check result normal?
YES <Except for GCC>:  Go to Step 17.
YES <Vehicles for GCC>:  Go to Step 18.
NO:  Repair or replace the connector.
Step 17. Check the wiring harness between B-18X A/C compressor relay connector (terminal 2) and C-112 engine-A/T-ECU connector (terminal 16).
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 18. Check the wiring harness between B-18X A/C compressor relay connector (terminal 2) and C-112 engine-A/T-ECU connector (terminal 8).
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 C-06 A/C-ECU connector.
  1. Disconnect C-06 A/C compressor connector and measure the voltage at the relay box side.
  1. Turn the ignition switch to the "ON" position.
  1. Disconnect C-112 engine-A/T-ECU connector, and earth terminal 21. <2400-except MIVEC>
  1. Disconnect C-134 engine-A/T-ECU connector, and earth terminal 16. <2400-MIVEC (except for GCC)>
  1. Disconnect C-134 engine-A/T-ECU connector, and earth terminal 8. <2400-MIVEC (vehicles for GCC)>
  1. Measure the voltage between terminal 7 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: B-18X A/C compressor relay connector and C-06 A/C-ECU connector
Q: Is the check result normal?
YES:  Go to Step 21.
NO:  Repair or replace the connector.
Step 21. Check the wiring harness between B-18X A/C compressor relay connector (terminal 1) and C-06 A/C-ECU connector (terminal 7).
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. Measure the voltage at C-06 A/C-ECU connector.
  1. Disconnect C-06 A/C-ECU connector and measure the voltage at the relay box side.
  1. Turn the ignition switch to the "ON" position.
  1. Turn the blower switch to the "ON" position.
  1. Measure the voltage between terminal 8 and earth.
    2. OK: System voltage
Q: Is the check result normal?
YES:  Go to Step 25.
NO:  Go to Step 23.
Step 23. Connector check: C-11 resistor connector and C-06 A/C-ECU connector
Q: Is the check result normal?
YES:  Go to Step 24.
NO:  Repair or replace the connector.
Step 24. Check the wiring harness between C-11 resistor connector (terminal 4) and C-06 A/C-ECU connector (terminal 8).
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 25. Check the magnetic clutch operation.
Refer to .
Q: Is the check result normal?
YES:  Go to Step 26.
NO:  Replace the compressor magnet clutch.
Step 26. Check the refrigerant temperature switch.
Refer to .
Q: Is the check result normal?
YES:  Go to Step 27.
NO:  Replace the refrigerant temperature switch.
Step 27. Check the air thermo sensor.
Refer to .
Q: Is the check result normal?
YES:  Go to Step 28.
NO:  Replace the air thermo sensor.
Step 28. Connector check: C-10 air thermo sensor connector and C-06 A/C-ECU connector
Q: Is the check result normal?
YES:  Go to Step 29.
NO:  Repair or replace the connector.
Step 29. Check the wiring harness between C-10 air thermo sensor connector (terminals 1, 3, 4 and 5) and C-06 A/C-ECU connector (terminals 14, 16 and 13).
Q: Is the check result normal?
YES:  Go to Step 30.
NO:  Repair the wiring harness.
Step 30. Check the refrigerant level.
Refer to .
Q: Is the check result normal?
YES:  Go to Step 31.
NO:  Refrigerant Draining and Refilling (Refer to and .)
Step 31. Check the A/C pressure sensor operation.
Refer to .
Q: Is the check result normal?
YES:  Go to Step 32.
NO:  Replace the A/C pressure sensor.
Step 32 Connector check: A-02 A/C pressure sensor connector and C-06 A/C-ECU connector
Q: Is the check result normal?
YES:  Go to Step 33.
NO:  Repair or replace the connector.
Step 33. Check the wiring harness between A-02 A/C pressure sensor connector (terminal 2) and C-06 A/C-ECU connector (terminal 15).
NOTE: Prior to the wiring harness inspection, check intermediate connector C-116, and repair if necessary.
Q: Is the check result normal?
YES <2400-except MIVEC>:  Go to Step 34.
YES <2400-MIVEC>:  Go to Step 37.
NO:  Repair the wiring harness.
Step 34. Connector check: C-110, C-111 engine-A/T-ECU connector and C-06 A/C-ECU connector
Q: Is the check result normal?
YES:  Go to Step 35.
NO:  Repair or replace the connector.
Step 35. Check the wiring harness between C-110 engine-A/T-ECU connector (terminal 83) and C-06 A/C-ECU connector (terminal 4).
NOTE: Prior to the wiring harness inspection, check intermediate connector C-104, and repair if necessary.
Q: Is the check result normal?
YES:  Go to Step 36.
NO:  Repair the wiring harness.
Step 36. Check the wiring harness between C-111 engine-A/T-ECU connector (terminal 61) and C-06 A/C-ECU connector (terminal 5).
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 manual air conditioner control panel (A/C-ECU) or engine-A/T-ECU.
NO:  Repair the wiring harness.
Step 37. Connector check: C-136 engine-A/T-ECU connector and C-06 A/C-ECU connector
Q: Is the check result normal?
YES:  Go to Step 38.
NO:  Repair or replace the connector.
Step 38. Check the wiring harness between C-136 engine-A/T-ECU connector (terminal 69 and 78) and C-06 A/C-ECU connector (terminal 4 and 5).
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 manual air conditioner control panel (A/C-ECU) or engine-A/T-ECU.
NO:  Repair the wiring harness.
[55A] HEATER, AIR CONDITIONER AND VENTILATION - - TROUBLESHOOTING - SYMPTOM PROCEDURES - INSPECTION PROCEDURE 3: When the A/C is Operating, Temperature Inside the Passenger Compartment does not Decrease (Cool Air is not Emitted).PRINT PAGE / INDEX / PRIOR / NEXT
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