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How To Proceed With Troubleshooting

HINT: 

  1. VEHICLE BROUGHT TO WORKSHOP 

    NEXT: Go to next step 

  2. CUSTOMER PROBLEM ANALYSIS 

    HINT: 

    • In troubleshooting, confirm that the problem symptoms have been accurately identified. Preconceptions should be discarded in order to make an accurate judgment. To clearly understand what the problem symptoms are, it is extremely important to ask the customer about the problem and the conditions at the time the malfunction occurred.
    • Gather as much information as possible for reference. Past problems that seem unrelated may also help in some cases.
    • The following 5 items are important points for problem analysis:
      What? Vehicle model, system name
      When? Date, time, occurrence frequency. Does it occur recently or for a long time?
      Where? Does it occur at specified place?
      Under what conditions? Unlock/lock the door, power switch on (IG), hybrid system start.
      How did it happen? Problem symptoms*
      • *: Be sure to ask the customer in detail about the following points concerning the vehicle operating conditions, environment and problem, and then check for DTCs.
        1. If the entry lock/unlock function does not operate for all doors.
        2. If the entry lock function does not operate.
        3. If the entry unlock function does not operate.
        4. If both the entry lock and unlock functions do not operate.
        5. If the wireless lock and unlock functions do not operate.
        6. If there is no power even when the power switch is pressed [does not turn on (ACC)].
        7. If the hybrid control system does not start with the push start function.
        8. If the wireless answer-back buzzer and outside warning buzzers do not sound.
        9. Did you try to hybrid control system start by put the electrical key transmitter sub-assembly direct on the power switch and press the power switch on (IG).
        10. If the interior warning buzzers do not sound.
        11. Any other details concerning the problem.
      • If it is supposed that electric wave interference is likely, be sure to ask the customer in detail about the following points concerning the vehicle operating conditions, environment and problem.
        1. Specific locations where the system does not operate (such as near TV towers, large video displays, wireless garage door opener systems, wireless security cameras, home security systems, etc.).
        2. Specific times when the system does not operate:

          Whether or not symptoms occurred immediately after purchase or only recently.

          Whether or not the symptoms occurred when the electrical key transmitter sub-assembly was even right by the vehicle (electrical key antenna).

        3. If the system does not operate only when near specific vehicles (there may be an effect from electric waves from the wireless systems of other vehicles).
        4. If the system operates intermittently.
        5. If the electrical key transmitter sub-assembly is bundled together with other items.
        6. If the electrical key transmitter sub-assembly is carried together with other electronic devices, such as cell phones, personal computers, portable music players, other electrical keys, etc. (keep the electrical key transmitter sub-assembly at least 0.1 m (0.33 ft.) away from such items).
        7. Where the electrical key transmitter sub-assembly is being kept when not in use:

          Whether or not the electrical key transmitter sub-assembly being placed within 1 m (3.28 ft.) of items such as TVs, DVD recorders, induction cookers, rice cookers, dishwashers, modems, cell phones, personal computers, microwave ovens, desk or floor lamps, cordless telephones, etc.

        8. If there are electronic devices that transmit electric waves placed in the vehicle.
        9. When the transmitter battery was last replaced (when the battery is low).

          The transmitter battery can be checked roughly using the "Key Low Battery" item in the Data List. Refer to DATA LIST / ACTIVE TEST .

        10. If the customer installed any optional components (theft deterrent devices, wireless fog lights, etc.) to the vehicle.

    NEXT: Go to next step 

  3. INSPECT AUXILIARY BATTERY VOLTAGE 
    1. Measure the auxiliary battery voltage with the power switch off.

      Standard voltage

      11 to 14 V

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

      NEXT: Go to next step 

  4. CHECK COMMUNICATION FUNCTION OF CAN COMMUNICATION SYSTEM* 
    1. Use the Techstream 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 → GO TO CAN COMMUNICATION SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING 

      A: Go to next step 

  5. CHECK COMMUNICATION FUNCTION OF LIN COMMUNICATION SYSTEM* 
    1. Use the Techstream to check if the LIN communication system is functioning normally.
      RESULT

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

      B → GO TO LIN COMMUNICATION SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING 

      A: Go to next step 

  6. CHECK FUNCTION OF WIRELESS DOOR LOCK CONTROL SYSTEM* 
    1. Use the Techstream to check if the wireless door lock control system is functioning normally.
      RESULT

      Result Proceed to
      Wireless door lock control system DTC is not output A
      Wireless door lock control system DTC is output B

      B → GO TO WIRELESS DOOR LOCK CONTROL SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING 

      A: Go to next step 

  7. CHECK FOR DTC* 
    1. Recheck for DTCs. Refer to DTC CHECK / CLEAR . Based on the DTCs output, proceed each system's DTC procedure.
      RESULT

      Result Proceed to
      DTC is not output A
      Engine immobiliser system DTC is output B
      Smart Key System (for Entry Function) DTC is output C

      B → GO TO ENGINE IMMOBILISER SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING 

      C → GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART  

      A: Go to next step 

  8. PROBLEM SYMPTOMS TABLE 
    1. Refer to Problem Symptoms Table. Refer to PROBLEM SYMPTOMS TABLE .
      RESULT

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

      B → Go to step 10 

      A: Go to next step 

  9. OVERALL ANALYSIS AND TROUBLESHOOTING* 
    1. Operation Check. Refer to OPERATION CHECK .
    2. Check Data List / Active Test. Refer to DATA LIST / ACTIVE TEST .
    3. Check Terminals of ECU. Refer to TERMINALS OF ECU .

      NEXT: Go to next step 

  10. REPAIR OR REPLACEMENT 

    NEXT: Go to next step 

  11. CHECK FOR DTC* 
    1. Clear the DTCs. Refer to DTC CHECK / CLEAR .
    2. Check for DTCs. Refer to DTC CHECK / CLEAR .

      HINT: 

      Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure. Refer to DIAGNOSTIC TROUBLE CODE CHART .

      RESULT

      Result Proceed to
      DTC is not output A
      Smart Key System (for Entry Function) DTC is output B

      B → GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART  

      A → END 

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