REAR POWER SEAT CONTROL SYSTEM, Diagnostic DTC:B2654

DTC Code DTC Name
B2654 Headrest Sensor Malfunction

DESCRIPTION

When the position control ECU does not receive a sensor signal despite forward or backward movement of the seat by power seat motor operation, this DTC is output.

DTC Code DTC Detection Condition Trouble Area
B2654 Sensor's forward and backward lock detection position is the same
  • Position control ECU

  • Rear No. 1 seat headrest adjuster sub-assembly

  • Harness or connector

WIRING DIAGRAM

A0018VVE07

PROCEDURE


  1. CHECK FOR DTC


    1. DTC output area check


      1. Using the intelligent tester, determine the area that output the DTC.

        Result
        Result Proceed to
        B2654 output from rear left seat ECU A
        B2654 output from rear right seat ECU B

    B
    A
  2. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (POWER SEAT MOTOR FUNCTION)


    1. Select the Active Test, use the intelligent tester to generate a control command, and then check the power seat motor function.

      Rear Left Seat
      Tester Display Test Part Control Range
      Headrest Operation Seat headrest operation UP / DOWN
      OK
      Motor operates normally.

    NG
    OK
  3. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU LH - REAR HEADREST MOTOR LH AND BODY GROUND)


    1. A001DF3E02
      *1 Front view of wire harness connector: (to Position Control ECU LH)
      *2 SSRH
      *3 Front view of wire harness connector: (to Rear Headrest Motor LH)
      *4 SSRV

      Disconnect the f41 ECU connector.

    2. Disconnect the f26 motor connector.

    3. Measure the resistance according to the values in the table below.

      Standard resistance
      Tester Connection Condition Specified Condition
      f41-17 (PVCC) - f26-4 (PVCC) Always Below 1 Ω
      f41-6 (SSRH) - f26-2 (SSRV) Always Below 1 Ω
      f41-23 (SGND) - f26-3 (GND) Always Below 1 Ω
      f41-17 (PVCC) - Body ground Always 10 kΩ or higher
      f41-6 (SSRH) - Body ground Always 10 kΩ or higher
      f41-23 (SGND) - Body ground Always 10 kΩ or higher

    NG
    OK
  4. CHECK REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POSITION CONTROL SENSOR)


    1. A00196IE01
      Front view of wire harness connector
      *1 (to Rear Headrest Motor LH)

      Disconnect the f26 motor connector.

    2. Measure the voltage according to the values in the table below.

      Standard voltage
      Tester Connection Switch Condition Specified Condition
      f26-4 (PVCC) - f26-3 (GND) Headrest switch ON 7.2 to 8.8 V
      Result
      Result Proceed to
      OK A
      NG (w/o Ottoman) B
      NG (w/ Ottoman) C

    B
    C
    A
  5. CHECK REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POSITION CONTROL SENSOR)


    1. A001F15E02
      *1 Component with harness connected: (Rear Headrest Motor LH)
      *2 SSRV

      Reconnect the f26 motor connector.

    2. Measure the voltage according to the value in the table below.

      Standard voltage
      Tester Connection Switch Condition Specified Condition
      f26-2 (SSRV) - Body ground Headrest switch ON 0 to 8 V
      Result
      Result Proceed to
      OK A
      NG (w/o Ottoman) B
      NG (w/ Ottoman) C

    B
    C
    A
  6. CHECK FOR DTC


    1. Clear the DTC Click here.

    2. Recheck the DTC.

      OK
      DTC B2654 is not output.
      Result
      Result Proceed to
      OK A
      NG (w/o Ottoman) B
      NG (w/ Ottoman) C

    A
    B
    C
  7. INSPECT REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POWER SEAT MOTOR)

    A001DAGE05
    *1 Component without harness connected: (Rear Headrest Motor LH)

    1. Disconnect the motor connector.

    2. Check operation of the power seat motor (headrest motor).

    3. Check if the seat headrest adjuster moves smoothly when the battery is connected to the headrest motor connector terminals.

      OK
      Measurement Condition Operational Direction

      Battery positive (+) → 5

      Battery negative (-) → 1

      Upward

      Battery positive (+) → 1

      Battery negative (-) → 5

      Downward
      Result
      Result Proceed to
      OK A
      NG (w/o Ottoman) B
      NG (w/ Ottoman) C

    B
    C
    A
  8. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU LH - REAR HEADREST MOTOR LH)


    1. A001AEUE03

      Disconnect the f24 ECU connector.

    2. Disconnect the f26 motor connector.

    3. Measure the resistance according to the values in the table below.

      Standard resistance
      Tester Connection Condition Specified Condition
      f24-5 (HUP) - f26-5 (UP) Always Below 1 Ω
      f24-12 (HDWN) - f26-1 (DOWN) Always Below 1 Ω
      Result
      Result Proceed to
      OK (w/o Ottoman) A
      OK (w/ Ottoman) B
      NG C

    A
    B
    C
  9. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (POWER SEAT MOTOR FUNCTION)


    1. Select the Active Test, use the intelligent tester to generate a control command, and then check the power seat motor function.

      Rear Right Seat
      Tester Display Test Part Control Range
      Headrest Operation Seat headrest operation UP / DOWN
      OK
      Motor operates normally.

    NG
    OK
  10. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU RH - REAR HEADREST MOTOR RH AND BODY GROUND)


    1. A001AGSE02
      *1 Front view of wire harness connector: (to Position Control ECU RH)
      *2 SSRH
      *3 Front view of wire harness connector: (to Rear Headrest Motor RH)
      *4 SSRV

      Disconnect the f38 ECU connector.

    2. Disconnect the f6 motor connector.

    3. Measure the resistance according to the values in the table below.

      Standard resistance
      Tester Connection Condition Specified Condition
      f38-17 (PVCC) - f6-4 (PVCC) Always Below 1 Ω
      f38-6 (SSRH) - f6-2 (SSRV) Always Below 1 Ω
      f38-23 (SGND) - f6-3 (GND) Always Below 1 Ω
      f38-17 (PVCC) - Body ground Always 10 kΩ or higher
      f38-6 (SSRH) - Body ground Always 10 kΩ or higher
      f38-23 (SGND) - Body ground Always 10 kΩ or higher

    NG
    OK
  11. CHECK REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POSITION CONTROL SENSOR)


    1. A0019W8E01
      Front view of wire harness connector
      *1 (to Rear Headrest Motor RH)

      Disconnect the f6 motor connector.

    2. Measure the voltage according to the values in the table below.

      Standard voltage
      Tester Connection Switch Condition Specified Condition
      f6-4 (PVCC) - f6-3 (GND) Headrest switch ON 7.2 to 8.8 V
      Result
      Result Proceed to
      OK A
      NG (w/o Ottoman) B
      NG (w/ Ottoman) C

    B
    C
    A
  12. CHECK REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POSITION CONTROL SENSOR)


    1. A001EGIE01
      *1 Component with harness connected: (Rear Headrest Motor RH)
      *2 SSRV

      Reconnect the f6 motor connector.

    2. Measure the voltage according to the value in the table below.

      Standard voltage
      Tester Connection Switch Condition Specified Condition
      f6-2 (SSRV) - Body ground Headrest switch ON 0 to 8 V
      Result
      Result Proceed to
      OK A
      NG (w/o Ottoman) B
      NG (w/ Ottoman) C

    B
    C
    A
  13. CHECK FOR DTC


    1. Clear the DTC Click here.

    2. Recheck the DTC.

      OK
      DTC B2654 is not output.
      Result
      Result Proceed to
      OK A
      NG (w/o Ottoman) B
      NG (w/ Ottoman) C

    A
    B
    C
  14. INSPECT REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POWER SEAT MOTOR)

    A001DAGE06
    *1 Component without harness connected: (Rear Headrest Motor RH)

    1. Disconnect the motor connector.

    2. Check operation of the power seat motor (headrest motor).

    3. Check if the seat headrest adjuster moves smoothly when the battery is connected to the headrest motor connector terminals.

      OK
      Measurement Condition Operational Direction

      Battery positive (+) → 5

      Battery negative (-) → 1

      Upward

      Battery positive (+) → 1

      Battery negative (-) → 5

      Downward
      Result
      Result Proceed to
      OK A
      NG (w/o Ottoman) B
      NG (w/ Ottoman) C

    B
    C
    A
  15. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU RH - REAR HEADREST MOTOR RH)


    1. A0019YJE04

      Disconnect the f4 ECU connector.

    2. Disconnect the f6 motor connector.

    3. Measure the resistance according to the values in the table below.

      Standard resistance
      Tester Connection Condition Specified Condition
      f4-5 (HUP) - f6-5 (UP) Always Below 1 Ω
      f4-12 (HDWN) - f6-1 (DOWN) Always Below 1 Ω
      Result
      Result Proceed to
      OK (w/o Ottoman) A
      OK (w/ Ottoman) B
      NG C

    A
    B
    C