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Home >> Lexus >> 2007 >> GS 450h >> Repair and Diagnosis >> Accessories & Equipment >> Headlights >> Lighting >> Lighting System >> Stop Light Circuit >> Inspection Procedure
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Inspection Procedure

  1. READ VALUE OF INTELLIGENT TESTER (STOP LIGHT SWITCH) 
    1. Select the DATA LIST, use the intelligent tester (with CAN VIM) to generate a control command, and then check that the stop light illuminates.

      Rear multiplex network ECU 

      DATA LIST

      Item Measurement Item / Display (Range) Normal Condition
      STOP LIGHT SW Stop light switch / ON or OFF ON: Brake pedal depressed
      OFF: Brake pedal released

      OK: Each light illuminates. 

    OK:  GO TO step  5

    NG: GO TO Next Step 

  2. INSPECT FUSE (STOP SW) 
    1. Remove the STOP SW fuse from the main body ECU RH.
    2. Measure the resistance of the fuse.

      Standard resistance: Below 1 Ω 

    NG: REPLACE FUSE 

    OK: GO TO Next Step 

  3. INSPECT STOP LIGHT SWITCH 
    1. Inspect the stop light switch (see INSPECTION  ).

      OK: Stop light switch is normal. 

    NG: REPLACE STOP LIGHT SWITCH 

    OK: GO TO Next Step 

  4. CHECK WIRE HARNESS (ECU - BATTERY) 
    1. Disconnect the LC ECU connector.
    2. Measure the voltage of the wire harness side connector.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      LC-32 (STP1) - Body ground Brake pedal is depressed 10 to 14 V
      Fig 1: Identifying LC ECU Connector Terminals
      G05315607Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: GO TO Next Step 

  5. PERFORM ACTIVE TEST BY INTELLIGENT TESTER (STOP LIGHT AND HIGH MOUNT STOP LIGHT) 
    1. Select the ACTIVE TEST, use the intelligent tester (with CAN VIM) to generate a control command, and then check that the stop light and high mount stop light illuminates.

      Rear multiplex network ECU 

      ACTIVE TEST

      Item Test Details
      STOP LIGHT Stop light ON / OFF
      H-M STOP LIGHT High mount stop light ON / OFF

      Result 

      RESULT REFERENCE CHART

      Result Proceed to
      Both stop light and high mount stop light do not illuminate A
      Stop light does not illuminate B
      High mount stop light does not illuminate C
      OK D

    B:  GO TO step  8

    C:  GO TO step  10

    D: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE 

    A: GO TO Next Step 

  6. INSPECT FUSE (STOP LP L, STOP LP R) 
    1. Remove the STOP LP L and STOP LP R fuses from the rear multiplex network ECU.
    2. Measure the resistance of the fuses.

      Standard resistance: Below 1 Ω 

    NG: REPLACE FUSE 

    OK: GO TO Next Step 

  7. CHECK WIRE HARNESS (ECU - BATTERY) 
    1. Disconnect the LB ECU connector.
    2. Measure the voltage of the wire harness side connector.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      LB-1 - Body ground 10 to 14 V
      Fig 2: Identifying LB ECU Connector Terminals
      G05315608Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE 

  8. CHECK WIRE HARNESS (REAR MULTIPLEX NETWORK ECU - REAR COMBINATION LIGHT AND BODY GROUND) 
    1. Check the wire harness between the rear combination light (stop LH) and rear multiplex network ECU, and the rear combination light (stop LH) and body ground.
      1. Disconnect the LG ECU connector.
      2. Disconnect the X1 light connector.
      3. Measure the resistance of the wire harness side connectors.

        Standard resistance 

        TESTER CONNECTION SPECIFIED CONDITION

        Tester Connection Specified Condition
        LG-7 (STP2) - X1-7 (STP) Below 1 Ω
        LG-7 (STP2) or X1-7 (STP) - Body ground 10 kΩ or higher
      4. Connect the LG ECU connector.
      5. Measure the resistance of the wire harness side connector.

        Standard resistance 

        TESTER CONNECTION SPECIFIED CONDITION

        Tester Connection Specified Condition
        X1-6 (E) - Body ground Below 1 Ω
        Fig 3: Identifying LG ECU And X1 Light Connector Terminals
        G05315609Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check the wire harness between the rear combination light (stop RH) and rear multiplex network ECU, and the rear combination light (stop RH) and body ground.
      1. Disconnect the LG ECU connector.
      2. Disconnect the X3 light connector.
      3. Measure the resistance of the wire harness side connectors.

        Standard resistance 

        TESTER CONNECTION SPECIFIED CONDITION

        Tester Connection Specified Condition
        LG-2 (STP3) - X3-2 (STP) Below 1 Ω
        LG-2 (STP3) or X3-2 (STP) - Body ground 10 kΩ or higher
      4. Connect the LG ECU connector.
      5. Measure the resistance of the wire harness side connector.

        Standard resistance 

        TESTER CONNECTION SPECIFIED CONDITION

        Tester Connection Specified Condition
        X3-6 (E) - Body ground Below 1 Ω
        Fig 4: Identifying LG ECU And X3 Light Connector Terminals
        G05315610Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: GO TO Next Step 

  9. REPLACE REAR COMBINATION LIGHT (STOP LH OR STOP RH) 
    1. Temporarily replace the rear combination light (stop LH or stop RH) with a new or normally functioning one.
    2. Check that the light illuminates.

      OK: Light illuminates. 

    OK: END 

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

  10. REPLACE NOISE FILTER 
    1. Temporarily replace the noise filter with a new or normally functioning one.
    2. Check that the light illuminates.

      OK: Light illuminates. 

    OK: END 

    NG: GO TO Next Step 

  11. REPLACE CENTER STOP LIGHT 
    1. Temporarily replace the center stop light with a new or normally functioning one.
    2. Check that the light illuminates.

      OK: Light illuminates. 

    OK: END 

    NG: GO TO Next Step 

  12. CHECK WIRE HARNESS (ECU - NOISE FILTER) 
    1. Disconnect the LA ECU connector.
    2. Disconnect the V18 noise filter connector.
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      LA-4 (STP1) - V18-2 Below 1 Ω
      LA-4 (STP1) or V18-2 - Body ground 10 kΩ or higher
      Fig 5: Identifying LA Rear Multiplex Network ECU And V18 Noise Filter
      G05315611Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: GO TO Next Step 

  13. CHECK WIRE HARNESS (NOISE FILTER - CENTER STOP LIGHT) 
    1. Disconnect the V18 noise filter connector.
    2. Disconnect the V24 light connector.
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      V18-1 -V24-1 Below 1 Ω
      V18-1 or V24-1 -Body ground 10 kΩ or higher
      Fig 6: Identifying V18 Noise Filter And V24 Center Stop Light Connector Terminals
      G05315612Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: GO TO Next Step 

  14. CHECK WIRE HARNESS (CENTER STOP LIGHT - BODY GROUND) 
    1. Disconnect the V24 light connector.
    2. Measure the resistance of the wire harness side connector.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      V24-2 - Body ground Below 1 Ω
      Fig 7: Identifying V24 Light Connector Terminals
      G05315613Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE 

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