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Home >> Mitsubishi >> 2021 >> Mirage G4 ES, Standard Trans >> Repair and Diagnosis >> Accessories & Equipment >> Anti-Theft Systems >> Keyless Entry System (Vehicles Without Keyless Operation System) >> Keyless Entry System Diagnosis >> Symptom Procedures >> Inspection Procedure 1: Keyless entry system does not work >> Diagnosis
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Inspection Procedure 1: Keyless entry system does not work: Diagnosis

  1. STEP 1. Check the power supply system. 

    With the ignition switch in the "LOCK" (OFF) position, check if the following function operates normally:

    • Hazard warning light

    Q: Is the check result normal? 

    YES:  Go to Step  2.

    NO:  Refer to Inspection Procedure A-1: Check the battery power supply circuit to the ETACS-ECU .

  2. STEP 2. Using scan tool (M.U.T-III), read the diagnostic trouble code. 
    CAUTION: To prevent damage to scan tool (M.U.T-III), always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool (M.U.T-III).
    1. Connect scan tool (M.U.T-III). Refer to "HOW TO CONNECT SCAN TOOL (M.U.T.-III) ."
    2. Turn the ignition switch to the "ON" position.
    3. Check whether the ETACS-ECU related DTC is set.
    4. Turn the ignition switch to the "LOCK" (OFF) position.

      Q: Is the DTC set? 

      YES:  Diagnose the ETACS-ECU. Refer to DIAGNOSTIC TROUBLE CODE CHART .

      NO:  Go to Step  3.

  3. STEP 3. Check the operation of the central door locking system. 

    Check that the central door locking system works normally.

    Q: Is the check result normal? 

    YES:  Go to Step  4.

    NO:  Refer to TROUBLE SYMPTOM CHART .

  4. STEP 4. Using scan tool (M.U.T-III), check data list. 

    Check the signals related to the power window operation.

    CAUTION: To prevent damage to scan tool (M.U.T-III), always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool (M.U.T-III).
    1. Connect scan tool (M.U.T-III). Refer to "HOW TO CONNECT SCAN TOOL (M.U.T.-III) ."
    2. Turn the ignition switch to the "ON" position.
    3. Check the data list of the ETACS.
      • Turn the ignition switch to the "LOCK" (OFF) position.
      • Remove the ignition key from the ignition key cylinder.
      • Close the driver's door.
      • Close the front passenger's doors.
      • Close the RH-side rear door.
      • Close the LH-side rear door.
    Item No. Item name Normal condition
    19 Driver's door switch OFF
    20 Driver's door unlock switch ON→OFF
    21 Driver's door lock switch OFF→ON
    28 Steering lock switch OFF
    48 Passenger's door switch OFF
    49 Rear door switch OFF

    OK: Normal condition are displayed. 

    Q: Are the check result normal? 

    YES <Normal conditions are displayed for all the items.>:  Go to Step  5.

    NO <Normal condition is not displayed for item No. 19.>:  Refer to INSPECTION PROCEDURE 5 "THE FRONT DOOR SWITCH (DRIVER'S SIDE) SIGNAL IS NOT RECEIVED ".

    NO <Normal condition is not displayed for item No. 20, 21.>:  Refer to INSPECTION PROCEDURE 4 "THE FRONT DOOR LOCK ACTUATOR (DRIVER'S SIDE) SIGNAL IS NOT RECEIVED ".

    NO <Normal condition is not displayed for item No. 28.>:  Refer to INSPECTION PROCEDURE 3: "THE KEY REMINDER SWITCH SIGNAL IS NOT RECEIVED ".

    NO <Normal condition is not displayed for item No. 48.>:  Refer to INSPECTION PROCEDURE 6 "THE FRONT DOOR SWITCH (PASSENGER'S SIDE) SIGNAL IS NOT RECEIVED . ".

    NO <Normal condition is not displayed for item No. 49.>:  Refer to INSPECTION PROCEDURE 7 "ONE OF THE DOOR SWITCH SIGNALS IS NOT RECEIVED ".

  5. STEP 5. Retest the system. 

    Check the keyless entry system works normally.

    Q: Is the check result normal? 

    YES:  The trouble can be an intermittent malfunction (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).

    NO:  Replace the ETACS-ECU.