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Inspection Procedure

  1. CHECK FOR DTC 
    1. Check for DTCs.
      1. Using the Techstream, check which ECU output the DTC.

        Result 

        RESULT CHART

        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 TECHSTREAM (POWER SEAT MOTOR FUNCTION) 
    1. Select the Active Test, use the Techstream to generate a control command, and then check the power seat motor function.

      Driver Seat 

      DIAGNOSTIC NOTE

      Tester Display Test Part Control Range Diagnostic Note
      Headrest Operation Seat headrest operation UP/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
      646-18 (SGND) - Body ground Always 10 kΩ or higher
      Fig 1: Checking Harness And Connector (Front Power Seat Switch LH - Front Headrest Motor LH)
      G04952467Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

      OK: Go to next step 

  4. CHECK FRONT POWER SEAT SWITCH LH 
    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 Switch Condition Specified Condition
      e53-2 (VCC) - e53-3 (GND) Headrest switch signal ON 7.2 to 8.8 V
      Fig 2: Identifying e53 Motor Connector Terminals
      G04952468Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

      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 Switch Condition Specified Condition
      e53-4 (O/P) - Body ground Headrest switch signal ON 0 to 8 V
      Fig 3: Identifying e53 Motor Connector Terminals
      G06194175Courtesy 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. Clear the DTCs (see DTC CHECK/CLEAR  ).
    2. Recheck for DTCs.

      OK: 

      DTC B2654 is not output. 

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

      OK: END (SYSTEM RETURNS TO NORMAL) 

  7. CHECK FRONT SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POWER SEAT MOTOR) 
    1. Check the 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 

        MEASUREMENT CONDITION CHART

        Measurement Condition Operation Direction
        Battery positive (+) → 1
        Battery negative (-) → 5        		 Seat headrest adjuster moves upward
        Battery positive (+) → 5
        Battery negative (-) → 1        		 Seat headrest adjuster moves downward
        Fig 4: Identifying Power Seat Motor Connector Terminals
        G04952470Courtesy 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: Checking Harness And Connector (Front Power Seat Switch LH - Front Headrest Motor LH)
      G04952471Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

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

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

      Result 

      RESULT CHART

      Result Proceed to
      w/ Folding Headrest A
      w/ Normal Headrest B

      B:  Go to step  17

      A: Go to next step 

  10. PERFORM ACTIVE TEST USING TECHSTREAM (POWER SEAT MOTOR FUNCTION) 
    1. Select the Active Test, use the Techstream to generate a control command, and then check the power seat motor function.

      Passenger Seat 

      DIAGNOSTIC NOTE

      Tester Display Test Part Control Range Diagnostic Note
      Headrest Operation Seat headrest operation UP/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: Checking Harness And Connector (Front Power Seat Switch RH - Front Headrest Position Sensor RH)
      G04952472Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

      OK: Go to next step 

  12. CHECK FRONT POWER SEAT SWITCH RH 
    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 Switch Condition Specified Condition
      e23-3 (VCC) - e23-2 (GND) Headrest switch signal ON 7.2 to 8.8 V
      Fig 7: Identifying e23 Sensor Connector Terminals
      G04952473Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

      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 Switch Condition Specified Condition
      e23-1 (O/P) - Body ground Headrest switch signal ON 0 to 8 V
      Fig 8: Identifying e23 Sensor Connector Terminals
      G06194180Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      NG: REPLACE FRONT SEAT HEADREST ADJUSTER (See  DISASSEMBLY   ) 

      OK: Go to next step 

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

      OK: 

      DTC B2654 is not output. 

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

      OK: END (SYSTEM RETURNS TO NORMAL) 

  15. CHECK POWER SEAT MOTOR ASSEMBLY 
    1. Check the 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 

        MEASUREMENT CONDITION CHART

        Measurement Condition Operation Direction
        Battery positive (+) → 1
        Battery negative (-) → 2        		 Seat headrest adjuster moves upward
        Battery positive (+) → 2
        Battery negative (-) → 1        		 Seat headrest adjuster moves downward
        Fig 9: Identifying Power Seat Motor Connector Terminals
        G04952427Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        NG: REPLACE POWER SEAT MOTOR ASSEMBLY (See REMOVAL   ) 

        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: Checking Harness And Connector (Front Power Seat Switch RH - Power Seat Motor)
      G04952476Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

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

  17. PERFORM ACTIVE TEST USING TECHSTREAM (POWER SEAT MOTOR FUNCTION) 
    1. Select the Active Test, use the Techstream to generate a control command, and then check the power seat motor function.

      Passenger Seat 

      DIAGNOSTIC NOTE

      Tester Display Test Part Control Range Diagnostic Note
      Headrest Operation Seat headrest operation UP/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) - e25-4 (VCC) Always Below 1 Ω
      e20-21 (SSRH) - e25-2 (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: Checking Harness And Connector (Front Power Seat Switch RH - Front Headrest Motor RH)
      G06194183Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

      OK: Go to next step 

  19. CHECK FRONT POWER SEAT SWITCH RH 
    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 Switch Condition Specified Condition
      e25-4 (VCC) - e25-3 (GND) Headrest switch signal ON 7.2 to 8.8 V
      Fig 12: Identifying e25 Sensor Connector Terminals
      G06194184Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

      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 Switch Condition Specified Condition
      e25-2 (O/P) - Body ground Headrest switch signal ON 0 to 8 V
      Fig 13: Identifying e25 Sensor Connector Terminals
      G06194185Courtesy 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. Clear the DTCs (see DTC CHECK/CLEAR  ).
    2. Recheck for DTCs.

      OK: 

      DTC B2654 is not output. 

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

      OK: END (SYSTEM RETURNS TO NORMAL) 

  22. CHECK FRONT SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POWER SEAT MOTOR) 
    1. Check the 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 

        MEASUREMENT CONDITION CHART

        Measurement Condition Operation Direction
        Battery positive (+) → 5
        Battery negative (-) → 1        		 Seat headrest adjuster moves upward
        Battery positive (+) → 1
        Battery negative (-) → 5        		 Seat headrest adjuster moves downward
        Fig 14: Identifying Power Seat Motor Connector Terminals
        G04952470Courtesy 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+) - e25-5 (UP) Always Below 1 Ω
      e18-8 (H-) - e25-1 (DOWN) Always Below 1 Ω
      Fig 15: Checking Harness And Connector (Front Power Seat Switch RH - Front Headrest Motor RH)
      G06194187Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

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

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