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Inspection Procedure

WARNING: This page is about a different car, the 2008 Toyota Yaris. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK WHETHER LIGHTS ILLUMINATE 
    1. Check whether the following lights illuminate: Front position lights, Rear taillights and License plate light.

      Result 

      RESULT CHART

      Illumination Condition Proceed To
      All lights do not Illuminate A
      Front position lights do not Illuminate B
      Front marker lights do not Illuminate C
      Rear taillights do not illuminate D
      License plate light does not illuminate E

    B: Go to step  10

    C: Go to step  12

    D: Go to step  14

    E: Go to step  16

    A: GO TO NEXT STEP 

  2. CHECK VEHICLE SPECIFICATIONS 
    1. Check the vehicle type.

      Result 

      RESULT CHART

      Vehicle Type Proceed To
      Hatchback, Sedan with front fog light (w/T-LP relay) A
      Sedan without front fog light (w/b T-LP relay) B

    B: Go to step  7

    A: GO TO NEXT STEP 

  3. INSPECT FUSE (TAIL) 
    1. Remove the TAIL fuse from the main body ECU.
    2. Measure the resistance.

      Standard resistance: Below 1 Ω 

    3. Reconnect the TAIL fuse.

    NG: REPLACE FUSE 

    OK: GO TO NEXT STEP 

  4. PERFORM ACTIVE TEST USING TECHSTREAM (TAIL LIGHT) 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch ON.
    3. Turn the tester on.
    4. Enter the following menus: Body Electrical / Main Body / Active Test / Taillight Relay
    5. Check the taillights while operating the taillight relay using the tester.

    Main Body ECU 

    ACTIVE TEST

    Tester Display Test Part Control Range
    Taillight Relay Taillight relay ON / OFF

    OK: Taillight comes on. 

    NG: PROCEED TO NEXT INSPECTION PROCEDURE SHOWN IN PROBLEM SYMPTOMS TABLE 

    OK: GO TO NEXT STEP 

  5. INSPECT HEADLIGHT DIMMER SWITCH 
    1. Remove the headlight dimmer switch.
    2. Inspect the light control switch.
    3. Measure the resistance.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      10(T1)-13(B1) TAIL Below 1 Ω
      10(T1)-13(B1) OFF 10 kΩ or higher
      10(T1)-13(B1) HEAD Below 1 Ω
      10(T1)-13(B1) OFF 10 kΩ or higher
    4. Reinstall the headlight dimmer switch.
      Fig 1: Identifying Terminals Of Headlight Dimmer Switch Connector
      G04832710Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE HEADLIGHT DIMMER SWITCH 

    OK: GO TO NEXT STEP 

  6. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - HEADLIGHT DIMMER SWITCH) 
    1. Disconnect the D4 headlight dimmer switch connector.
    2. Measure the voltage.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      D4-13(B1)-Body Ground 11 to 14 V
    3. Reconnect the headlight dimmer switch connector.
      4. Fig 2: Identifying Terminals Of D4 Headlight Dimmer Switch Connector
      G04832711Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (HEADLIGHT DIMMER SWITCH - BODY GROUND) 

  7. INSPECT FUSE (TAIL) 
    1. Remove the TAIL fuse from the main body ECU.
    2. Measure the resistance.

      Standard resistance: Below 1 Ω 

    3. Reconnect the TAIL fuse.

    NG: REPLACE FUSE 

    OK: GO TO NEXT STEP 

  8. INSPECT HEADLIGHT DIMMER SWITCH 
    1. Remove the headlight dimmer switch.
    2. Inspect the light control switch.
    3. Measure the resistance.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      10(T1)-13(B1) TAIL Below 1 Ω
      10(T1)-13(B1) OFF 10 kΩ or higher
      10(T1)-13(B1) HEAD Below 1 Ω
      10(T1)-13(B1) OFF 10 kΩ or higher
    4. Reinstall the headlight dimmer switch.
      5. Fig 3: Identifying Terminals Of Headlight Dimmer Switch Connector
      G04832710Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE HEADLIGHT DIMMER SWITCH 

    OK: GO TO NEXT STEP 

  9. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - HEADLIGHT DIMMER SWITCH) 
    1. Disconnect the D4 headlight dimmer switch connector.
    2. Disconnect the 4M and 4E main body ECU connectors.
    3. Measure the resistance.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      D4-13(B1)-4M-4 Below 1 Ω
      D4-10(T1)-4E-10 Below 1 Ω
      D4-13 (B1) or 4M-4 - Body Ground 10 kΩ or higher
      D4-10 (T1) or 4E-10 - Body Ground 10 kΩ or higher
    4. Reconnect the headlight dimmer switch connector.
    5. Reconnect the main body ECU connectors.
      6. Fig 4: Identifying Terminals Of D4 Headlight Dimmer Switch Connector
      G04832713Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE MAIN BODY ECU 

  10. INSPECT BULB (FRONT POSITION LIGHT BULB) 
    1. Hatchback:
      1. Remove the front position light.
      2. Apply battery voltage to the terminals and check that the front position light illuminates.

        Standard 

        TERMINALS VOLTAGES CHART

        Measurement Condition Standard
        Positive battery - Terminal 1
        Negative battery - Terminal 2        		 Front position light Illuminates
      3. Reinstall the front position light.
        Fig 5: Identifying Terminals Of Front Position Light Connector
        G04832714Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Sedan:
      1. Remove the front position light.
      2. Apply battery voltage to the terminals and check that the front position light illuminates.

        Standard 

        TERMINALS VOLTAGES CHART

        Measurement Condition Standard
        Positive battery - Terminal 3
        Negative battery - Terminal 2        		 Front position light illuminates
      3. Reinstall the front position light.
      3. Fig 6: Identifying Terminals Of Front Position Light Connector
      G04832715Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE BULB 

    OK: GO TO NEXT STEP 

  11. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - FRONT POSITION LIGHT) 
    1. Hatchback:
      1. Disconnect the B3 and B4 front position light connectors.
      2. Disconnect the 4B main body ECU connector.
      3. Measure the resistance.

        Standard resistance 

        TESTER CONNECTION SPECIFIED CONDITION CHART

        Tester Connection Specified Condition
        4B-33 - B3-1 Below 1 Ω
        4B-33 - B7-1 Below 1 Ω
        4B-33 or B3-1 - Body ground 10 kΩ or higher
        4B-33 or B7-1 - Body ground 10 kΩ or higher
      4. Reconnect the front position light connectors.
      5. Reconnect the main body ECU connector.
        Fig 7: Identifying Terminals Of 4B Main Body ECU Connector
        G04832716Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Sedan:
      1. Disconnect the B14 and B15 front position light connectors.
      2. Disconnect the 4B main body ECU connector.
      3. Measure the resistance.

        Standard resistance 

        TESTER CONNECTION SPECIFIED CONDITION CHART

        Tester Connection Specified Condition
        4B-33 - B14-3 Below 1 Ω
        4B-33-B15-3 Below 1 Ω
        4B-33 or B14-3 - Body ground 10 kΩ or higher
        4B-33 or B15-3 - Body ground 10 kΩ or higher
      4. Reconnect the front position light connectors.
      5. Reconnect the main body ECU connector.
        6. Fig 8: Identifying Terminals Of 4B Main Body ECU Connector
        G04832717Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (FRONT POSITION LIGHT - BODY GROUND) 

  12. INSPECT BULB (FRONT MARKER LIGHT) 
    1. Hatchback:
      1. Remove the front marker light.
      2. Apply battery voltage to the terminals and check that the front marker light illuminates.

        Standard 

        TERMINALS VOLTAGES CHART

        Measurement Condition Standard
        Positive battery - Terminal 2
        Negative battery - Terminal 1        		 Front marker light Illuminates
      3. Reinstall the front marker light.
        Fig 9: Identifying Terminals Of Front Marker Light Connector
        G04832718Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Sedan:
      1. Remove the front marker light.
      2. Apply battery voltage to the terminals and check that the front marker light illuminates.

        Standard 

        TERMINALS VOLTAGES CHART

        Measurement Condition Standard
        Positive battery - Terminal 4
        Negative battery - Terminal 2        		 Front marker light illuminates
      3. Reinstall the front marker light.
      3. Fig 10: Identifying Terminals Of Front Marker Light Connector
      G04832719Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE BULB 

    OK: GO TO NEXT STEP 

  13. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - FRONT MARKER LIGHT) 
    1. Hatchback:
      1. Disconnect the B11 and B12 front marker light connectors.
      2. Disconnect the 4B main body ECU connector.
      3. Measure the resistance.

        Standard resistance 

        TESTER CONNECTION SPECIFIED CONDITION CHART

        Tester Connection Specified Condition
        4B-33-B11-2 Below 1 Ω
        4B-33-B12-2 Below 1 Ω
        4B-33 or B11-2 - Body ground 10 kΩ or higher
        4B-33 or B12-2 - Body ground 10 kΩ or higher
      4. Reconnect the front marker light connectors.
      5. Reconnect the main body ECU connector.
        Fig 11: Identifying Terminals Of 4B Main Body ECU Connector
        G04832720Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Sedan:
      1. Disconnect the B14 and B15 front marker light connectors.
      2. Disconnect the 4B main body ECU connector.
      3. Measure the resistance.

        Standard resistance 

        TESTER CONNECTION SPECIFIED CONDITION CHART

        Tester Connection Specified Condition
        4B-33 - B14-4 Below 1 Ω
        4B-33-B15-4 Below 1 Ω
        4B-33 or B14-4 - Body ground 10 kΩ or higher
        4B-33 or B15-4 - Body ground 10 kΩ or higher
      4. Reconnect the front marker light connectors.
      5. Reconnect the main body ECU connector.
      3. Fig 12: Identifying Terminals Of 4B Main Body ECU Connector
      G04832721Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (FRONT MARKER LIGHT - BODY GROUND) 

  14. INSPECT BULB (REAR TAILLIGHT BULB) 
    1. Hatchback:
      1. Remove the rear combination light assembly.
      2. Apply battery voltage to the terminals and check that the rear taillight illuminates.

        Standard 

        TERMINALS VOLTAGES CHART

        Measurement Condition Standard
        Positive battery - Terminal 4
        Negative battery - Terminal 6        		 Rear taillight Illuminates
      3. Reinstall the rear combination light assembly.
        Fig 13: Identifying Terminals Of Rear Combination Light Assembly Connector
        G04832722Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Sedan:
      1. Remove the rear combination light assembly.
      2. Apply battery voltage to the terminals and check that the rear taillight illuminates.

        Standard 

        TERMINALS VOLTAGES CHART

        Measurement Condition Standard
        Positive battery - Terminal 4
        Negative battery - Terminal 6        		 Rear taillight Illuminates
      3. Reinstall the rear combination light assembly.
      3. Fig 14: Identifying Terminals Of Rear Combination Light Assembly Connector
      G04832723Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE BULB 

    OK: GO TO NEXT STEP 

  15. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - REAR TAILLIGHT) 
    1. Hatchback:
      1. Disconnect the J3 and J4 rear combination light assembly connectors.
      2. Disconnect the 4A main body ECU connector.
      3. Measure the resistance.

        Standard resistance 

        TESTER CONNECTION SPECIFIED CONDITION CHART

        Tester Connection Specified Condition
        4A-10-J3-4 Below 1 Ω
        4A-29-J4-4 Below 1 Ω
        4A-10 or J3-4-Body ground 10 kΩ or higher
        4A-29 or J4-4 Body ground 10 kΩ or higher
      4. Reconnect the rear combination light assembly connectors.
      5. Reconnect the main body ECU connector.
        Fig 15: Identifying Terminals Of 4A Main Body ECU Connector
        G04832724Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Sedan:
      1. Disconnect the J34 and J35 rear combination light assembly connectors.
      2. Disconnect the 4A main body ECU connector.
      3. Measure the resistance.

        Standard resistance 

        TESTER CONNECTION SPECIFIED CONDITION CHART

        Tester Connection Specified Condition
        4A-10-J34-4 Below 1 Ω
        4A-29 J35-4 Below 1 Ω
        4A-10 or J34-4 - Body ground 10 kΩ or higher
        4A-29 or J35-4 - Body ground 10 kΩ or higher
      4. Reconnect the rear combination light assembly connectors.
      5. Reconnect the main body ECU connector.
      3. Fig 16: Identifying Terminals Of 4A Main Body ECU Connector
      G04832725Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (REAR TAILLIGHT - BODY GROUND) 

  16. INSPECT BULB (LICENSE PLATE LIGHT BULB) 
    1. Hatchback:
      1. Remove the license plate light assembly.
      2. Apply battery voltage to the terminals and check that the license plate light illuminates.

        Standard 

        TERMINALS VOLTAGES CHART

        Measurement Condition Standard
        Positive battery - Terminal 2
        Negative battery - Terminal 1        		 License plate light illuminates
      3. Reinstall the license plate light assembly.
        Fig 17: Identifying Terminals Of License Plate Light Assembly Connector
        G04832726Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Sedan:
      1. Remove the license plate light assembly.
      2. Apply battery voltage to the terminals and check that the license plate light illuminates.

        Standard 

        TERMINALS VOLTAGES CHART

        Measurement Condition Standard
        Positive battery - Terminal 2
        Negative battery - Terminal 1        		 License plate light Illuminates
      3. Reinstall the license plate light assembly.
      3. Fig 18: Identifying Terminals Of License Plate Light Assembly Connector
      G04832727Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE BULB 

    OK: GO TO NEXT STEP 

  17. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - LICENSE PLATE LIGHT ASSEMBLY) 
    1. Hatchback:
      1. Disconnect the L1 license plate light assembly connector.
      2. Disconnect the 4A main body ECU connector.
      3. Measure the resistance.

        Standard resistance 

        TESTER CONNECTION SPECIFIED CONDITION CHART

        Tester Connection Specified Condition
        4A-29-L1-2 Below 1 Ω
        4A-29 or L1-2 - Body ground 10 kΩ or higher
      4. Reconnect the license plate light assembly connector.
      5. Reconnect the main body ECU connector.
        Fig 19: Identifying Terminals Of L1 License Plate Light Assembly Connector
        G04832728Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Sedan:
      1. Disconnect the J36 and J37 license plate light assembly connectors.
      2. Disconnect the 4A main body ECU connector.
      3. Measure the resistance.

        Standard resistance 

        TESTER CONNECTION SPECIFIED CONDITION CHART

        Tester Connection Specified Condition
        4A-29 - J36-2 Below 1 Ω
        4A-29 - J37-2 Below 1 Ω
        4A-29 or J36-2 - Body ground 10 kΩ or higher
        4A-29 or J37-2 - Body ground 10 kΩ or higher
      4. Reconnect the license plate light assembly connectors.
      5. Reconnect the main body ECU connector.
      3. Fig 20: Identifying Terminals Of 4A Main Body ECU Connector
      G04832729Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (LICENSE PLATE LIGHT ASSEMBLY - BODY GROUND) 

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