AIR CONDITIONING SYSTEM (for Automatic Air Conditioning System) HOW TO PROCEED WITH TROUBLESHOOTING

Tech Tips


  • Use these procedures to troubleshoot the air conditioning system.

  • *: Use the intelligent tester.


  1. VEHICLE BROUGHT TO WORKSHOP


    NEXT
  2. CUSTOMER PROBLEM ANALYSIS AND SYMPTOM CHECK


    NEXT
  3. INSPECT BATTERY VOLTAGE


    1. Measure the voltage of the battery.

      Standard voltage
      11 to 14 V

      If the voltage is below 11 V, recharge or replace the battery before proceeding to the next step.

    2. w/ PTC Heater:

      Using the intelligent tester, inspect battery voltage reduction history "Battery Voltage Lo Record" in the Data List Click here.


      NEXT
  4. CHECK COMMUNICATION FUNCTION OF CAN COMMUNICATION SYSTEM*


    1. Use the intelligent tester to check if the CAN communication system is functioning normally.

      Result
      Result Proceed to
      CAN DTC is not output A
      CAN DTC is output B

      B
      A
  5. CHECK PANEL DIAGNOSIS


    1. Check panel diagnosis Click here.


      1. Indicator Check

      2. Sensor Check


      NEXT
  6. CHECK FOR DTC*


    1. Check for DTCs and note any codes that are output Click here.

    2. Clear the DTCs Click here.

    3. Based on the DTCs output above, try to force output of the air conditioning system DTC by simulating the conditions indicated by the DTC. Then recheck for DTCs.

      Result
      Result Proceed to
      DTC is not output A
      DTC is output B

      B
      A
  7. PROBLEM SYMPTOMS TABLE


    1. Refer to the Problem Symptoms Table Click here.

      Result
      Result Proceed to
      Fault is not listed in problem symptoms table A
      Fault is listed in problem symptoms table B

      B
      A
  8. OVERALL ANALYSIS AND TROUBLESHOOTING*


    1. Terminals of ECU Click here

    2. Data List / Active Test Click here

    3. On-vehicle Inspection

    4. Inspection


      NEXT
  9. ADJUST, REPAIR OR REPLACE


    NEXT
  10. CONFIRMATION TEST


    NEXT