LEMON Manuals: Even more car manuals for everyone
Home >> Lexus >> 2010 >> GS 350 RWD >> Repair and Diagnosis >> Accessories & Equipment >> Exterior Lights >> Lighting (Diagnostic Codes & Circuit Tests) >> Lighting System >> Turn Signal Light Circuit >> Procedure

Turn Signal Light Circuit: Procedure

  1. CHECK OPERATION OF TURN SIGNAL LIGHT 
    1. When the turn signal light switch is operated, check that the appropriate turn signal light flashes.

      Result

      Result Proceed to
      All lights do not flash A
      Headlight assembly (turn LH or turn RH) does not flash B
      Side turn signal light assembly (LH or RH) does not flash C
      Rear combination light (turn LH or turn RH) does not flash D

    D → See step   11 

    C → See step   9 

    B → See step   7 

    A: Go to next step 

  2. PERFORM ACTIVE TEST USING TECHSTREAM 
    1. Select the Active Test, use the Techstream to generate a control command, and then check that the turn signal light flashes.

      Cowl side junction block ECU LH

      Item Test Details Diagnostic Note
      Turn Lamp RH Turn signal light operation ON / OFF -
      Turn Lamp LH Turn signal light operation ON / OFF -

      OK

      Turn signal light flashes.

    NG → See step   3 

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

  3. INSPECT FUSE (TURN-HAZ, LH-IG) 
    1. Remove the LH-IG fuse from the cowl side junction block LH.
    2. Remove the TURN-HAZ fuse from the engine room No. 1 junction block.
    3. Measure the resistance of the fuses.

      Standard resistance

      Below 1 Ω

    NG → REPLACE FUSE 

    OK: Go to next step 

  4. CHECK WIRE HARNESS (TURN SIGNAL FLASHER - BATTERY AND BODY GROUND) 
    1. Disconnect the K25 flasher connector.
      Fig 1: Checking Wire Harness (Turn Signal Flasher - Battery And Body Ground)
      GTY108288Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance of the wire harness side connector.

      Standard voltage

      Tester Connection Condition Specified Condition
      K25-1 (IG) - Body ground Engine switch on (IG) 10 to 14 V
      K25-4 (B) - Body ground Always 10 to 14 V

      Standard resistance

      Tester Connection Specified Condition
      K25-7 (E) - Body ground Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  5. CHECK WIRE HARNESS (TURN SIGNAL FLASHER - COWL SIDE JUNCTION BLOCK LH) 
    1. Disconnect the K25 flasher connector.
      Fig 2: Checking Wire Harness (Turn Signal Flasher - Cowl Side Junction Block LH)
      GTY103940Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the PA junction block connector.
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance

      Tester Connection Specified Condition
      K25-5 (EL) - PA-16 (TL) Below 1 Ω
      K25-6 (ER) - PA-15 (TR) Below 1 Ω
      K25-5 (EL) or PA-16 (TL) - Body ground 10 kΩ or higher
      K25-6 (ER) or PA-15 (TR) - Body ground 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  6. REPLACE TURN SIGNAL FLASHER 
    1. Temporarily replace the turn signal flasher with a new or normally functioning one.
    2. Check that the turn signal flasher operates.

      OK

      Front turn signal light bulb (turn LH) flashes.

    OK → END 

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

  7. REPLACE FRONT TURN SIGNAL LIGHT BULB (TURN LH OR TURN RH) 
    1. Temporarily replace the front turn signal light bulb (turn LH or turn RH) with a new or normally functioning one.
    2. Check that the front turn signal light bulb (turn LH or turn RH) flashes.

      OK

      Front turn signal light bulb (turn LH or turn RH) flashes.

    OK → END 

    NG: Go to next step 

  8. CHECK WIRE HARNESS (TURN SIGNAL FLASHER - HEADLIGHT ASSEMBLY (TURN LH OR TURN RH) - BODY GROUND) 
    1. Check the wire harness between the headlight (turn LH) and turn signal flasher, and the headlight (turn LH) and body ground.
      Fig 3: Identifying Turn Signal Flasher - Headlight Assembly (Turn LH) Connector Terminals
      GTY108199Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Disconnect the K25 flasher connector.
      2. Disconnect the B11 headlight connector.
      3. Measure the resistance of the wire harness side connectors.

        Standard resistance

        Tester Connection Specified Condition
        K25-3 (LL) - B11-9 Below 1 Ω
        K25-3 (LL) or B11-9 - Body ground 10 kΩ or higher
        B11-8 - Body ground Below 1 Ω
    2. Check the wire harness between the headlight (turn RH) and turn signal flasher, and the headlight (turn RH) and body ground.
      Fig 4: Identifying Turn Signal Flasher - Headlight Assembly (Turn RH) Connector Terminals
      GTY100125Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Disconnect the K25 flasher connector.
      2. Disconnect the B2 headlight connector.
      3. Measure the resistance of the wire harness side connectors.

        Standard resistance

        Tester Connection Specified Condition
        K25-2 (LR) - B2-9 Below 1 Ω
        K25-2 (LR) or B2-9 - Body ground 10 kΩ or higher
        B2-8 - Body ground Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS AND CONNECTOR 

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

  9. REPLACE SIDE TURN SIGNAL LIGHT ASSEMBLY (LH OR RH) 
    1. Temporarily replace the side turn signal light assembly (LH or RH) with a new or normally functioning one.
    2. Check that the side turn signal light assembly (LH or RH) flashes.

      OK

      Side turn signal light assembly (LH or RH) flashes.

    OK → END 

    NG: Go to next step 

  10. CHECK WIRE HARNESS (TURN SIGNAL FLASHER - SIDE TURN SIGNAL LIGHT ASSEMBLY (LH OR RH) - BODY GROUND) 
    1. Check the wire harness between the side turn signal light assembly (LH) and turn signal flasher, and the side turn signal light assembly (LH) and body ground.
      Fig 5: Identifying K25 Flasher Connector And Side Turn Signal Light Assembly Connector
      GTY102565Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Disconnect the K25 flasher connector.
      2. Disconnect the side turn signal light assembly connector.
      3. Measure the resistance of the wire harness side connectors.

        Standard resistance

        Tester Connection Specified Condition
        K25-3 (LL) - 2 (Side turn signal light assembly) Below 1 Ω
        K25-3 (LL) - Body ground 10 kΩ or higher
        1 (Side turn signal light assembly) - Body ground Below 1 Ω
    2. Check the wire harness between the side turn signal light assembly (RH) and turn signal flasher, and the side turn signal light assembly (RH) and body ground.
      Fig 6: Identifying K25 Flasher Connector And Side Turn Signal Light Assembly Connector
      GTY108452Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Disconnect the K25 flasher connector.
      2. Disconnect the side turn signal light assembly connector.
      3. Measure the resistance of the wire harness side connectors.

        Standard resistance

        Tester Connection Specified Condition
        K25-2 (LR) - 2 (Side turn signal light assembly) Below 1 Ω
        K25-2 (LR) - Body ground 10 kΩ or higher
        1 (Side turn signal light assembly) - Body ground Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS AND CONNECTOR 

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

  11. REPLACE REAR COMBINATION LIGHT BULB (TURN LH OR TURN RH) 
    1. Temporarily replace the rear combination light bulb (turn LH or turn RH) with a new or normally functioning one.
    2. Check that the rear combination light bulb (turn LH or turn RH) flashes.

      OK

      Rear combination light bulb (turn LH or turn RH) flashes.

    OK → END 

    NG: Go to next step 

  12. CHECK WIRE HARNESS (TURN SIGNAL FLASHER - REAR COMBINATION LIGHT (TURN LH OR TURN RH) - BODY GROUND) 
    1. Check the wire harness between the rear combination light (turn LH) and turn signal flasher, and the rear combination light (turn LH) and body ground.
      Fig 7: Identifying Turn Signal Flasher - Rear Combination Light (Turn LH) Connector Terminals
      GTY108201Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Disconnect the K25 flasher connector.
      2. Disconnect the X1 combination light connector.
      3. Measure the resistance of the wire harness side connectors.

        Standard resistance

        Tester Connection Specified Condition
        K25-3 (LL) - X1-4 (TRN) Below 1 Ω
        K25-3 (LL) or X1-4 (TRN) - Body ground 10 kΩ or higher
        X1-6 (E) - Body ground Below 1 Ω
    2. Check the wire harness between the rear combination light (turn RH) and turn signal flasher, and the rear combination light (turn RH) and body ground.
      1. Disconnect the K25 flasher connector.
        Fig 8: Identifying Turn Signal Flasher - Rear Combination Light (Turn RH) Connector Terminals
        GTY108200Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Disconnect the X3 combination light connector.
      3. Measure the resistance of the wire harness side connectors.

        Standard resistance

        Tester Connection Specified Condition
        K25-2 (LR) - X3-8 (TRN) Below 1 Ω
        K25-2 (LR) or X3-8 (TRN) - Body ground 10 kΩ or higher
        X3-6 (E) - Body ground Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS AND CONNECTOR 

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

scientia non olet · About LEMON Manuals