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How To Proceed With Troubleshooting

HINT:

  1. VEHICLE BROUGHT TO WORKSHOP 
  2. CUSTOMER PROBLEM ANALYSIS CHECK 

    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 in the problem analysis:
    VEHICLE PROBLEM TABLE

    What Vehicle model, system name
    When Date, time, occurrence frequency
    Where Road conditions
    Under what conditions? Running conditions, driving conditions, weather conditions
    How did it happen? Problem symptoms
  3. INSPECT BATTERY VOLTAGE 

    Standard Voltage: 11 to 14 V 

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

  4. INSPECT COMMUNICATION FUNCTION OF MULTIPLEX COMMUNICATION SYSTEM (BEAN) 
    1. Use the intelligent tester to check if the Multiplex Communication System (MPX) is functioning normally (See MULTIPLEX COMMUNICATION SYSTEM ).

    Result 

    COMMUNICATION FUNCTION OF MULTIPLEX COMMUNICATION SYSTEM (BEAN)

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

    B: GO TO  MULTIPLEX COMMUNICATION SYSTEM 

    A: Go To Next Step 

  5. CHECK FOR DTC 
    1. Check for DTC and note any codes that are output (See DTC CHECK/CLEAR  ).
    2. Delete DTC.
    3. Recheck DTC.

    Result 

    FOR DTC

    Result Proceed to
    DTC does not reoccur A
    DTC reoccurs B

    B: GO TO  DIAGNOSTIC TROUBLE CODE TABLE  

    A: Go To Next Step 

  6. INSPECT BASIC OPERATION 
    1. Turn the engine switch on (START) and check that the engine starts normally. Make sure the brake pedal is depressed and the shift position is in P at this time.
    2. Check that the engine switch mode can be changed by pushing the engine switch.

    HINT:

    Without depressing the brake pedal, push the engine switch repeatedly. Engine switch mode should turn from off to on (ACC) to on (IG) and back to off.

    With the brake pedal depressed, push the engine switch repeatedly. Engine switch mode should turn to ENGINE START from any status.

    OK: 

    Engine can start normally. 

  7. PROBLEM SYMPTOMS TABLE 

    Result 

    PROBLEM SYMPTOMS TABLE

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

    B: Go to step   9 

    A: Go To Next Step 

  8. OVERALL ANALYSIS AND TROUBLESHOOTING 
    1. See TERMINALS OF ECU 
    2. See DATA LIST/ACTIVE TEST 
  9. REPAIR OR REPLACE 
  10. CONFIRMATION TEST 

END