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Inspection Procedure

WARNING: This page is about a different car, the 2008 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: When replacing the ABS & TRACTION actuator assembly, perform zero point calibration (See CALIBRATION  ).

HINT:

After steps  1,  2 and  3 are completed, start the inspection from step  4 when using Telecaster and start from step  5 when not using Telecaster.

  1. CHECK STOP LIGHT SWITCH OPERATION 
    1. Check that the stop light comes on when the brake pedal is depressed, and goes off when the brake pedal is released.

      OK: 

      Stop light switch function is normal. 

      HINT:

      Check the stop light bulb as it may have burnt out.

    NG:  Go to step  9

    OK: Go to next step 

  2. INSPECT SKID CONTROL ECU (STP1 TERMINAL VOLTAGE) 
    1. Disconnect the skid control ECU connector.
    2. Measure the voltage according to the value(s) in the table below.

      Voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      A34-27 (STP1) - Body ground Stop light switch ON (Brake pedal depressed) 8 to 14 V
      A34-27 (STP1) - Body ground Stop light switch OFF (Brake pedal released) Below 1.5 V
      Fig 1: Identifying Skid Control ECU Connector Terminals (STP1 Terminal Voltage)
      G05406732Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Result 

      RESULT CHART

      Result Proceed to
      OK (w/ Dynamic radar cruise control) A
      OK (w/o Dynamic radar cruise control) B
      NG C

    B:  Go to step  8

    C : REPAIR OR REPLACE HARNESS OR CONNECTOR (STP1 CIRCUIT) 

    A: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (STP1 TO STP2 CIRCUIT) 
    1. Measure the resistance according to the value(s) in the table below.

      Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      A34-27 (STP1) - A34-21 (STP2) Below 1 Ω
      A34-27 (STP1) - Body ground 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (STP1 TO STP2 CIRCUIT) 

    Fig 2: Identifying Skid Control ECU Connector Terminals (STP1 To STP2 Circuit)
    G05406733Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  4. PERFORM ACTIVE TEST BY TECHSTREAM (STOP LIGHT RELAY) 
    1. Reconnect the skid control ECU connector.
    2. Connect Telecaster to the DLC3.
    3. Turn the ignition switch on (IG) and turn Telecaster main switch on.
    4. Select "ACTIVE TEST" on Telecaster.

      ACTIVE LIST: ABS / VSC / TRAC 

      ACTIVE LIST

      Item Vehicle Condition / Test Details Diagnostic Note
      Stop Light Relay Turns stop light operation relay ON/OFF Observe rear combination light (Does not come on for 5 sec. or more)
    5. Check that "ON" and "OFF" of the stop light can be shown on the rear combination light by Telecaster.

      OK: 

      The stop light turns on or off in accordance with Telecaster. 

      HINT:

      Reinstall the sensors, connectors, etc. and restore the vehicle to its prior conditions before rechecking for DTCs.

    OK:  Go to step  8

    NG: Go to next step 

  5. INSPECT ENGINE ROOM R/B (BRK RELAY POWER SOURCE TERMINAL VOLTAGE) 
    1. Remove the BRK relay.
    2. Turn the ignition switch on (IG).
    3. Measure the voltage according to the value(s) in the table below.

      Voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      2 - Body ground IG switch on (IG) 8 to 14 V
      5 - Body ground IG switch on (IG) 8 to 14 V

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT) 

    Fig 3: Identifying BRK Relay Terminal
    G05406734Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  6. INSPECT BRK RELAY 
    1. Measure the resistance according to the value(s) in the table below.

      Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      3 - 4 Below 1 Ω
      3 - 5 10 kΩ or higher
      3 - 4 10 kΩ or higher (When battery positive voltage is applied to terminal 1 and battery negative voltage to terminal 2.)
      3 - 5 Below 1 Ω (When battery positive voltage is applied to terminal 1 and battery negative voltage to terminal 2.)

    NG: REPLACE BRK RELAY 

    Fig 4: Inspecting BRK Relay
    G05406735Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  7. INSPECT SKID CONTROL ECU CONNECTOR (STPO TERMINAL VOLTAGE) 
    1. Install the stop light operation (DAC) relay.
    2. Disconnect the skid control ECU connector.
    3. Turn the ignition switch on (IG).
    4. Measure the voltage according to the value(s) in the table below.

      Voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      A34-16 (STPO) -Body ground IG switch on (IG) 10 to 14 V

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

    Fig 5: Identifying Skid Control ECU Connector Terminals (STPO Terminal Voltage)
    G05406736Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  8. RECONFIRM DTC 
    1. Clear the DTC.
    2. Depress the brake pedal several times to test the stop light circuit.
    3. Check if the same DTC is detected.

      HINT:

      Reinstall the sensors, connectors, etc. and restore the vehicle to its prior conditions before rechecking for DTCs.

      Result 

      RESULT CHART

      Result Proceed to
      DTC is output A
      DTC is not output B

    B : END 

    A : REPLACE ABS & TRACTION ACTUATOR ASSEMBLY 

  9. INSPECT STOP LIGHT SWITCH ASSEMBLY (POWER SOURCE TERMINAL VOLTAGE) 
    1. Disconnect the stop light switch connector.
    2. Measure the voltage according to the value(s) in the table below.

      Voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      A23-2 - Body ground Always 10 to 14 V

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT) 

    Fig 6: Identifying Stop Light Switch Connector
    G05406737Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  10. INSPECT STOP LIGHT SWITCH ASSEMBLY 
    1. Disconnect the stop light switch assembly connector.
    2. Measure the resistance according to the value(s) in the table below.

      Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Switch Condition Tester Connection Specified Condition
      Switch pin free 1 - 2 Below 1 Ω
      Switch pin pushed in 1 - 2 10 kΩ or higher
      Fig 7: Inspecting Stop Light Switch Assembly
      G05406738Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Result 

      RESULT CHART

      Result Proceed to
      OK (w/ Dynamic radar cruise control) A
      OK (w/o Dynamic radar cruise control) B
      NG C

    B:  Go to step  14

    C : REPLACE STOP LIGHT SWITCH ASSEMBLY 

    A: Go to next step 

  11. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH TO BRK RELAY) 
    1. Remove the BRK relay.
    2. Measure the resistance according to the value(s) in the table below.

      Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      A23-1 -BRK relay 4 Below 1 Ω
      A23-1 - Body ground 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT SWITCH TO BRK RELAY) 

    Fig 8: Identifying Stop Light Switch Connector Terminal
    G05406739Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  12. INSPECT BRK RELAY 
    1. Measure the resistance according to the value(s) in the table below.

      Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      3 - 4 Below 1 Ω

    NG: REPLACE BRK RELAY 

    Fig 9: Inspecting BRK Relay Terminal
    G05406740Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  13. CHECK HARNESS AND CONNECTOR (BETWEEN REAR COMBINATION LIGHT, BODY GROUND AND BRK RELAY) 
    1. Disconnect the rear combination light connector.
    2. Measure the resistance according to the value(s) in the table below.

      Resistance 

      LH: 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      K25-2 - BRK relay 3 Below 1 Ω
      K25-1 - Body ground 10 kΩ or higher
      K25-3 - Body ground Below 1 Ω

      RH: 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      K29-2 - BRK relay 3 Below 1 Ω
      K29-1 - Body ground 10 kΩ or higher
      K29-3 - Body ground Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT CIRCUIT) 

    Fig 10: Identifying Rear Combination Light Connector
    G05406741Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : END 

  14. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH TO SKID CONTROL ECU) 
    1. Disconnect the stop light switch connector and skid control ECU connector.
    2. Measure the resistance according to the value(s) in the table below.

      Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      A34-27 (STP1) - A23-1 (STP) Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT SWITCH TO SKID CONTROL ECU) 

    Fig 11: Identifying Stop Light Switch Connector And Skid Control ECU Connector
    G05406742Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT CIRCUIT) 

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