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 upward or downward movement of the seat by power seat motor operation, this DTC is output.

DTC Code DTC Detection Condition Trouble Area
B2654 Sensor's upward and downward lock detection position is the same

  • Position control ECU

  • Rear No. 1 seat headrest adjuster sub-assembly

  • Harness or connector

WIRING DIAGRAM

A01H1XOE13

INSPECTION PROCEDURE

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

    PERFORM ACTIVE TEST USING INTELLIGENT TESTER (POWER SEAT MOTOR FUNCTION) Click here

    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 Diagnostic Note
      Headrest Operation Seat headrest operation Up / OFF / Down -
      OK
      Motor operates normally.

    NG

    INSPECT REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POWER SEAT MOTOR) Click here

    OK

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


    1. A01GZK3E05

      Disconnect the f43 ECU connector.

    2. Disconnect the f26 motor connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance
      Tester Connection Condition Specified Condition
      f43-17 (PVCC) - f26-4 (PVCC) Always Below 1 Ω
      f43-6 (SSRH) - f26-2 (SSRV) Always Below 1 Ω
      f43-23 (SGND) - f26-3 (GND) Always Below 1 Ω
      f43-17 (PVCC) - Body ground Always 10 kΩ or higher
      f43-6 (SSRH) - Body ground Always 10 kΩ or higher
      f43-23 (SGND) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. A01H18EE02

      Disconnect the f26 motor connector.

    2. Measure the voltage according to the value(s) 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 (except Ottoman) B
      NG (for Ottoman) C

    B

    REPLACE POSITION CONTROL ECU LH Click here

    C

    REPLACE POSITION CONTROL ECU LH Click here

    A

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


    1. A01H27YE04

      Reconnect the f26 motor connector.

    2. Measure the voltage according to the value(s) 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 (except Ottoman) B
      NG (for Ottoman) C

    B

    REPLACE REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY Click here

    C

    REPLACE REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY Click here

    A

  6. CHECK FOR DTC


    1. Clear the DTC Click here.

    2. Recheck for DTC.

      OK
      DTC B2654 is not output.
      Result
      Result Proceed to
      OK A
      NG (except Ottoman) B
      NG (for Ottoman) C

    B

    REPLACE POSITION CONTROL ECU LH Click here

    C

    REPLACE POSITION CONTROL ECU LH Click here

    A

    USE SIMULATION METHOD TO CHECK Click here

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


    1. A01H228E05

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

    2. 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 (except Ottoman) B
      NG (for Ottoman) C

    B

    REPLACE REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY Click here

    C

    REPLACE REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY Click here

    A

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


    1. A01GXFZE01

      Disconnect the f24 ECU connector.

    2. Disconnect the f26 motor connector.

    3. Measure the resistance according to the value(s) 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 (except Ottoman) A
      OK (for Ottoman) B
      NG C

    B

    REPLACE POSITION CONTROL ECU LH Click here

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    A

    REPLACE POSITION CONTROL ECU LH Click here

  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 Diagnostic Note
      Headrest Operation Seat headrest operation Up / OFF / Down -
      OK
      Motor operates normally.

    NG

    INSPECT REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POWER SEAT MOTOR) Click here

    OK

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


    1. A01GZK3E06

      Disconnect the f39 ECU connector.

    2. Disconnect the f6 motor connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance
      Tester Connection Condition Specified Condition
      f39-17 (PVCC) - f6-4 (PVCC) Always Below 1 Ω
      f39-6 (SSRH) - f6-2 (SSRV) Always Below 1 Ω
      f39-23 (SGND) - f6-3 (GND) Always Below 1 Ω
      f39-17 (PVCC) - Body ground Always 10 kΩ or higher
      f39-6 (SSRH) - Body ground Always 10 kΩ or higher
      f39-23 (SGND) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. A01H18EE03

      Disconnect the f6 motor connector.

    2. Measure the voltage according to the value(s) 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 (except Ottoman) B
      NG (for Ottoman) C

    B

    REPLACE POSITION CONTROL ECU RH Click here

    C

    REPLACE POSITION CONTROL ECU RH Click here

    A

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


    1. A01H27YE05

      Reconnect the f6 motor connector.

    2. Measure the voltage according to the value(s) 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 (except Ottoman) B
      NG (for Ottoman) C

    B

    REPLACE REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY Click here

    C

    REPLACE REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY Click here

    A

  13. CHECK FOR DTC


    1. Clear the DTC Click here.

    2. Recheck for DTC.

      OK
      DTC B2654 is not output.
      Result
      Result Proceed to
      OK A
      NG (except Ottoman) B
      NG (for Ottoman) C

    B

    REPLACE POSITION CONTROL ECU RH Click here

    C

    REPLACE POSITION CONTROL ECU RH Click here

    A

    USE SIMULATION METHOD TO CHECK Click here

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


    1. A01H228E06

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

    2. 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 (except Ottoman) B
      NG (for Ottoman) C

    B

    REPLACE REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY Click here

    C

    REPLACE REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY Click here

    A

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


    1. A01GXFZE02

      Disconnect the f4 ECU connector.

    2. Disconnect the f6 motor connector.

    3. Measure the resistance according to the value(s) 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 (except Ottoman) A
      OK (for Ottoman) B
      NG C

    B

    REPLACE POSITION CONTROL ECU RH Click here

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    A

    REPLACE POSITION CONTROL ECU RH Click here