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Inspection Procedure

WARNING: This page is about a different car, the 2008 Lexus LS 600hL. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK FOR DTC 
    1. DTC output area check
      1. Using the intelligent tester or Techstream, determine the area that output the DTC.

        Result 

    RESULT REFERENCE

    Result Proceed to
    B2654 output from driver seat ECU A
    B2654 output from passenger seat ECU B

    B:  Go to step  9

    A: Go to Next Step 

  2. PERFORM ACTIVE TEST USING INTELLIGENT TESTER OR TECHSTREAM (POWER SEAT MOTOR FUNCTION) 
    1. Select the ACTIVE TEST, use the intelligent tester or Techstream to generate a control command, and then check the power seat motor function
      1. Intelligent tester

        D-SEAT 

        D-SEAT REFERENCE

        Tester Display Test Part Control Range Diagnostic Note
        HEADREST Seat headrest operation UP / OFF / DOWN -
      2. Techstream

        Driver Seat 

    DRIVER SEAT REFERENCE

    Tester Display Test Part Control Range Diagnostic Note
    Headrest Operation Seat headrest operation Up / OFF / Down -

    OK: Motor operates normally 

    NG:  Go to step  7

    OK: Go to Next Step 

  3. CHECK HARNESS AND CONNECTOR (FRONT POWER SEAT SWITCH LH - FRONT HEADREST MOTOR LH) 
    1. Disconnect the e46 switch connector.
    2. Disconnect the e53 motor connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

    TESTER CONNECTION / SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    e46-8 (PVCC) - e53-2 (VCC) Always Below 1 Ω
    e46-21 (SSRH) - e53-4 (O/P) Always Below 1 Ω
    e46-18 (SGND) - e53-3 (GND) Always Below 1 Ω
    e46-8 (PVCC) - Body ground Always 10 kΩ or higher
    e46-21 (SSRH) - Body ground Always 10 kΩ or higher
    e46-18 (SGND) - Body ground Always 10 kΩ or higher
    Fig 1: Identifying Terminals Of E46 Switch And E53 Motor Connectors
    G05784841Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next Step 

  4. CHECK FRONT SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POSITION CONTROL SENSOR) 
    1. Disconnect the e53 motor connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

    TESTER CONNECTION / SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    e53-2 (VCC) - e53-3 (GND) Headrest switch signal ON 7.2 to 8.8 V
    Fig 2: Identifying Terminals Of E53 Motor Connector
    G05784842Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FRONT POWER SEAT SWITCH LH  (See DISASSEMBLY )

    OK: Go to Next Step 

  5. CHECK FRONT SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POSITION CONTROL SENSOR) 
    1. Reconnect the e53 motor connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

    TESTER CONNECTION / SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    e53-4 (O/P) - Body ground Headrest switch signal ON 0 to 8 V
    Fig 3: Identifying Terminals Of E53 Motor Connector
    G05784843Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FRONT SEAT HEADREST ADJUSTER SUB-ASSEMBLY  (See DISASSEMBLY )

    OK: Go to Next Step 

  6. CHECK FOR DTC 
    1. Recheck for the DTC (see DTC CHECK / CLEAR )

      OK: DTC B2654 is not output. 

      NG: REPLACE FRONT POWER SEAT SWITCH LH  (See DISASSEMBLY )

    OK: USE SIMULATION METHOD TO CHECK  (See HOW TO PROCEED WITH TROUBLESHOOTING )

  7. CHECK FRONT SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POWER SEAT MOTOR) 
    1. Check operation of the power seat motor (headrest motor).
      1. Check if the seat headrest adjuster moves smoothly when the battery is connected to the headrest motor connector terminals.

        OK 

    TERMINALS REFERENCE CHART

    Measurement Condition Operational Direction
    Battery positive (+) → 1
    Battery negative (-) → 5    		 Upward
    Battery positive (+) → 5
    Battery negative (-) → 1    		 Downward
    Fig 4: Identifying Terminals Of Power Seat Motor Connector
    G05784844Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FRONT SEAT HEADREST ADJUSTER SUB-ASSEMBLY  (See DISASSEMBLY )

    OK: Go to Next Step 

  8. CHECK HARNESS AND CONNECTOR (FRONT POWER SEAT SWITCH LH - FRONT HEADREST MOTOR LH) 
    1. Disconnect the e45 switch connector.
    2. Disconnect the e53 motor connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

    TESTER CONNECTION / SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    e45-11 (H+) - e53-1 (UP) Always Below 1 Ω
    e45-8 (H-) - e53-5 (DOWN) Always Below 1 Ω
    Fig 5: Identifying Terminals Of E45 Switch And E53 Motor Connectors
    G05784845Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE FRONT POWER SEAT SWITCH LH  (See DISASSEMBLY )

  9. CHECK VEHICLE 
    1. Check the type of headrest.

      Result 

    RESULT REFERENCE

    Result Proceed to
    w/ Folding headrest A
    w/o Folding headrest B

    B:  Go to step  17

    A: Go to Next Step 

  10. PERFORM ACTIVE TEST USING INTELLIGENT TESTER OR TECHSTREAM (POWER SEAT MOTOR FUNCTION) 
    1. Select the ACTIVE TEST, use the intelligent tester or Techstream to generate a control command, and then check the power seat motor function.
      1. Intelligent tester

        P-SEAT 

        P-SEAT REFERENCE

        Tester Display Test Part Control Range Diagnostic Note
        HEADREST Seat headrest operation UP/OFF/DOWN -
      2. Techstream

        Passenger Seat 

    PASSENGER SEAT REFERENCE

    Tester Display Test Part Control Range Diagnostic Note
    Headrest Operation Seat headrest operation Up / OFF / Down -

    OK: Motor operates normally 

    NG:  Go to step  15

    OK: Go to Next Step 

  11. CHECK HARNESS AND CONNECTOR (FRONT POWER SEAT SWITCH RH - FRONT HEADREST POSITION SENSOR RH) 
    1. Disconnect the e20 switch connector.
    2. Disconnect the e23 sensor connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

    TESTER CONNECTION / SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    e20-8 (PVCC) - e23-3 (VCC) Always Below 1 Ω
    e20-21 (SSRH) - e23-1 (O/P) Always Below 1 Ω
    e20-18 (SGND) - e23-2 (GND) Always Below 1 Ω
    e20-8 (PVCC) - Body ground Always 10 kΩ or higher
    e20-21 (SSRH) - Body ground Always 10 kΩ or higher
    e20-18 (SGND) - Body ground Always 10 kΩ or higher
    Fig 6: Identifying Terminals Of E20 Switch And E23 Sensor Connectors
    G05784846Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next Step 

  12. CHECK FRONT SEAT HEADREST ADJUSTER (POSITION CONTROL SENSOR) 
    1. Disconnect the e23 sensor connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

    TESTER CONNECTION / SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    e23-3 (VCC) - e23-2 (GND) Headrest switch signal ON 7.2 to 8.8 V
    Fig 7: Identifying Terminals Of E23 Sensor Connector
    G05784847Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FRONT POWER SEAT SWITCH RH  (See DISASSEMBLY )

    OK: Go to Next Step 

  13. CHECK FRONT SEAT HEADREST ADJUSTER (POSITION CONTROL SENSOR) 
    1. Reconnect the e23 sensor connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

    TESTER CONNECTION / SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    e23-1 (O/P) - Body ground Headrest switch signal ON 0 to 8 V
    Fig 8: Identifying Terminals Of E23 Sensor Connector
    G05784848Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FRONT SEAT HEADREST ADJUSTER  (See DISASSEMBLY )

    OK: Go to Next Step 

  14. CHECK FOR DTC 
    1. Recheck for the DTC (see DTC CHECK / CLEAR ).

      OK: DTC B2654 is not output. 

      NG: REPLACE FRONT POWER SEAT SWITCH RH  (See DISASSEMBLY )

    OK: USE SIMULATION METHOD TO CHECK  (See HOW TO PROCEED WITH TROUBLESHOOTING )

  15. CHECK POWER SEAT MOTOR ASSEMBLY 
    1. Check operation of the power seat motor (headrest motor)
      1. Check if the seat headrest adjuster moves smoothly when the battery is connected to the headrest motor connector terminals

        OK 

    TERMINALS REFERENCE CHART

    Measurement Condition Operational Direction
    Battery positive (+) → 1
    Battery negative (-) → 2    		 Upward
    Battery positive (+) → 2
    Battery negative (-) → 1    		 Downward
    Fig 9: Identifying Terminals Of Power Seat Motor Connector
    G05784849Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE POWER SEAT MOTOR ASSEMBLY  (See DISASSEMBLY )

    OK: Go to Next Step 

  16. CHECK HARNESS AND CONNECTOR (FRONT POWER SEAT SWITCH RH - POWER SEAT MOTOR) 
    1. Disconnect the e18 switch connector.
    2. Disconnect the e26 motor connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

    TESTER CONNECTION / SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    e18-11 (H+) - e26-1 Always Below 1 Ω
    e18-8 (H-) - e26-2 Always Below 1 Ω
    Fig 10: Identifying Terminals Of E18 Switch And E26 Motor Connectors
    G05784850Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE FRONT POWER SEAT SWITCH RH  (See DISASSEMBLY )

  17. PERFORM ACTIVE TEST USING INTELLIGENT TESTER OR TECHSTREAM (POWER SEAT MOTOR FUNCTION) 
    1. Select the ACTIVE TEST, use the intelligent tester or Techstream to generate a control command, and then check the power seat motor function
      1. Intelligent tester

        P-SEAT 

        P-SEAT REFERENCE

        Item Test Part Diagnostic Note Diagnostic Note
        HEADREST Seat headrest operation UP / OFF / DOWN -
      2. Techstream

        Passenger Seat 

    PASSENGER SEAT REFERENCE

    Item Test Part Diagnostic Note Diagnostic Note
    Headrest Operation Seat headrest operation Up / OFF / Down -

    OK: Motor operates normally 

    NG:  Go to step  22

    OK: Go to Next Step 

  18. CHECK HARNESS AND CONNECTOR (FRONT POWER SEAT SWITCH RH - FRONT HEADREST MOTOR RH) 
    1. Disconnect the e20 switch connector.
    2. Disconnect the e25 motor connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

    TESTER CONNECTION / SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    e20-8 (PVCC) - e25-2 (VCC) Always Below 1 Ω
    e20-21 (SSRH) - e25-4 (O/P) Always Below 1 Ω
    e20-18 (SGND) - e25-3 (GND) Always Below 1 Ω
    e20-8 (PVCC) - Body ground Always 10 kΩ or higher
    e20-21 (SSRH) - Body ground Always 10 kΩ or higher
    e20-18 (SGND) - Body ground Always 10 kΩ or higher
    Fig 11: Identifying Terminals Of E20 Switch And E25 Motor Connectors
    G05784851Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next Step 

  19. CHECK FRONT SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POSITION CONTROL SENSOR) 
    1. Disconnect the e25 sensor connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

    TESTER CONNECTION / SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    e25-2 (VCC) - e25-3 (GND) Headrest switch signal ON 7.2 to 8.8 V
    Fig 12: Identifying Terminals Of E25 Sensor Connector
    G05784852Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FRONT POWER SEAT SWITCH RH  (See DISASSEMBLY )

    OK: Go to Next Step 

  20. CHECK FRONT SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POSITION CONTROL SENSOR) 
    1. Reconnect the e25 sensor connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

    TESTER CONNECTION / SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    e25-4 (O/P) - Body ground Headrest switch signal ON 0 to 8 V
    Fig 13: Identifying Terminals Of E25 Sensor Connector
    G05784853Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FRONT SEAT HEADREST ADJUSTER SUB-ASSEMBLY  (See DISASSEMBLY )

    OK: Go to Next Step 

  21. CHECK FOR DTC 
    1. Recheck for the DTC (see DTC CHECK / CLEAR ).

      OK: DTC B2654 is not output. 

      NG: REPLACE FRONT POWER SEAT SWITCH RH  (See DISASSEMBLY )

      OK: USE SIMULATION METHOD TO CHECK  (See HOW TO PROCEED WITH TROUBLESHOOTING )

  22. CHECK FRONT SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POWER SEAT MOTOR) 
    1. Check operation of the power seat motor (headrest motor)
      1. Check if the seat headrest adjuster moves smoothly when the battery is connected to the headrest motor connector terminals.

        OK 

    TERMINALS REFERENCE CHART

    Measurement Condition Operational Direction
    Battery positive (+) → 1
    Battery negative (-) → 5    		 Upward
    Battery positive (+) → 5
    Battery negative (-) → 1    		 Downward
    Fig 14: Identifying Terminals Of Power Seat Motor Connector
    G05784854Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FRONT SEAT HEADREST ADJUSTER SUB-ASSEMBLY  (See DISASSEMBLY )

    OK: Go to Next Step 

  23. CHECK HARNESS AND CONNECTOR (FRONT POWER SEAT SWITCH RH - FRONT HEADREST MOTOR RH) 
    1. Disconnect the e18 switch connector.
    2. Disconnect the e25 motor connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

    TESTER CONNECTION / SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    e18-11 (H+) - e25-1 (UP) Always Below 1 Ω
    e18-8 (H-) - e25-5 (DOWN) Always Below 1 Ω
    Fig 15: Identifying Terminals Of E18 Switch And E25 Motor Connectors
    G05784855Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE FRONT POWER SEAT SWITCH RH  (See DISASSEMBLY )

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