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Home >> Lexus >> 2007 >> RX 400h FWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 307 (Brake Control System) >> Vehicle Stability Control System >> DTC C1380/64 Stop Light Control Relay Malfunction >> Inspection Procedure
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Inspection Procedure

WARNING: This page is about a different car, the 2008 Toyota FJ Cruiser. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: When replacing the master cylinder solenoid, perform zero point calibration (See CALIBRATION  ).
  1. CHECK STOP LIGHT SWITCH OPERATION 
    1. Check that the stop lights come on when the brake pedal is depressed and go off when the brake pedal is released.

      OK 

      STOP LIGHT SWITCH OPERATION CHART

      Pedal Condition Illumination Condition
      Brake pedal depressed ON
      Brake pedal released OFF

      HINT:

      Check the stop light bulbs as they may have burnt out.

    NG: CHECK STOP LIGHT SWITCH CIRCUIT 

    OK: Go to next step 

  2. INSPECT SKID CONTROL ECU TERMINAL VOLTAGE (STP) 
    1. Disconnect the skid control ECU connector.
      2. Fig 1: Identifying Skid Control ECU Connector Terminal
      G05579863Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage.

      Standard voltage 

      VOLTAGE SPECIFICATION

      Tester Connection Switch condition Specified Condition
      A4-7 (STP) - Body ground Brake pedal depressed 8 to 14 V
      A4-7 (STP) - Body ground Brake pedal released Below 1.5 V

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT) 

    OK: Go to next step 

  3. INSPECT SKID CONTROL ECU TERMINAL VOLTAGE (STP2) 
    1. Disconnect the skid control ECU connector.
      2. Fig 2: Identifying Skid Control ECU Connector Terminals
      G05112324Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the ignition switch to ON.
    3. Measure the resistance.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      A4-7 (STP) - A4-45 (STP2) Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (STP2 CIRCUIT) 

    OK: Go to next step 

  4. PERFORM ACTIVE TEST USING TECHSTREAM (STOP LIGHT RELAY) 
    1. Connect a Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the tester on.
    4. Select the following menu items: Chassis / ABS/VSC/ TRAC/ Active Test

      Select the "Stop Light Relay" in the Active Test and operate the stop light relay using the Techstream.

      ACTIVE TEST: ABS/VSC/TRAC 

      ABS/VSC/TRAC ACTIVE TEST REFERENCE

      Tester Display Test Part Control Range Diagnostic Note
      Stop Light Relay Stop light relay Stop light relay ON or OFF Observe stop lights
    5. Check that the stop lights turn on and off on the rear combination light when using the Techstream.

      OK: 

      The stop lights turn on and off according to the Techstream operations. 

    NG:  Go to step  6

    OK: Go to next step 

  5. RECONFIRM DTC 
    1. Clear the DTC (See DTC CHECK/CLEAR  ).
    2. Check if the same DTC is recorded (See DTC CHECK/CLEAR  ).

      Result 

      RESULT CHART

      Result Proceed to
      DTC output A
      DTC not output B

    B: END 

    A: REPLACE MASTER CYLINDER SOLENOID  (See DISASSEMBLY )

  6. CHECK STOP LP CTRL RELAY 
    1. Disconnect the STOP LP CTRL relay.
      2. Fig 3: Identifying STOP LP CTRL Relay Terminal
      G05199280Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the ignition switch to ON.
    3. Measure the voltage.

      Standard voltage 

      VOLTAGE SPECIFICATION

      Tester Connection Condition Specified Condition
      Terminal 5 - Body ground Always 8 to 14 V
      Terminal 1 - Body ground Always 8 to 14 V

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  7. INSPECT STOP CTRL LP RELAY 
    1. Remove the STOP LP CTRL relay from the engine room R/B No. 2.
      2. Fig 4: Identifying STOP LP CTRL Relay Terminals
      G04965497Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      3-4 Below 1 Ω
      3-5 10 kΩ or higher
    3. Measure the resistance.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Condition Specified Condition
      3-4 Battery voltage applied between terminals 1 (+) and 2 (-) 10 kΩ or higher
      3-5 Battery voltage applied between terminals 1 (+) and 2 (-) Below 1 Ω

    NG: REPLACE STOP LP CTRL RELAY 

    OK: Go to next step 

  8. INSPECT SKID CONTROL ECU TERMINAL VOLTAGE (STPO) 
    1. Disconnect the skid control ECU connector.
      2. Fig 5: Identifying Skid Control ECU Terminal Voltage (STPO)
      G05112328Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the ignition switch to ON.
    3. Measure the voltage.

      Standard voltage 

      VOLTAGE SPECIFICATION

      Tester Connection Condition Specified Condition
      A4-16 (STPO) - Body ground Brake pedal depressed 11 to 14 V

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (STPO CIRCUIT) 

    OK: Go to next step 

  9. RECONFIRM DTC 
    1. Clear the DTC (See DTC CHECK/CLEAR  ).
    2. Check if the same DTC is recorded (See DTC CHECK/CLEAR  ).

      Result 

      RESULT CHART

      Result Proceed to
      DTC output A
      DTC not output B

    B: END 

    A: REPLACE MASTER CYLINDER SOLENOID  (See DISASSEMBLY )

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