REAR POWER SEAT CONTROL SYSTEM, Diagnostic DTC:B2657

DTC Code DTC Name
B2657 Ottoman 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
B2657 Sensor's forward and backward lock detection position is the same

  • Position control ECU

  • Rear seat adjuster assembly

  • Harness or connector

WIRING DIAGRAM

A01GL7UE02

INSPECTION PROCEDURE

PROCEDURE


  1. 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 (for LHD)
      Tester Display Test Part Control Range
      Ottoman Seat ottoman operation UP / DOWN
      Rear Left Seat (for RHD)
      Tester Display Test Part Control Range
      Ottoman Seat ottoman operation UP / DOWN
      OK
      Motor operates normally.

    NG

    INSPECT REAR SEAT ADJUSTER ASSEMBLY (POWER SEAT MOTOR) Click here

    OK

  2. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU - REAR POWER SEAT MOTOR AND BODY GROUND)

    A01GMJPE01

    1. for LHD:


      1. Disconnect the f38 ECU connector.

      2. Disconnect the f16 motor connector.

    2. for RHD:


      1. Disconnect the f41 ECU connector.

      2. Disconnect the f33 motor connector.

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

      Standard resistance
      for LHD
      Tester Connection Condition Specified Condition
      f38-17 (PVCC) - f16-4 (PVCC) Always Below 1 Ω
      f38-9 (SSRO) - f16-2 (SSRO) Always Below 1 Ω
      f38-23 (SGND) - f16-3 (GND) Always Below 1 Ω
      f38-17 (PVCC) - Body ground Always 10 kΩ or higher
      f38-9 (SSRO) - Body ground Always 10 kΩ or higher
      f38-23 (SGND) - Body ground Always 10 kΩ or higher
      for RHD
      Tester Connection Condition Specified Condition
      f41-17 (PVCC) - f33-4 (PVCC) Always Below 1 Ω
      f41-9 (SSRO) - f33-2 (SSRO) Always Below 1 Ω
      f41-23 (SGND) - f33-3 (GND) Always Below 1 Ω
      f41-17 (PVCC) - Body ground Always 10 kΩ or higher
      f41-9 (SSRO) - Body ground Always 10 kΩ or higher
      f41-23 (SGND) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK REAR SEAT ADJUSTER ASSEMBLY (POSITION CONTROL SENSOR)

    A01GI5BE01

    1. for LHD:

      Disconnect the f16 motor connector.

    2. for RHD:

      Disconnect the f33 motor connector.

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

      Standard voltage
      for LHD
      Tester Connection Switch Condition Specified Condition
      f16-4 (PVCC) - f16-3 (GND) Ottoman switch ON 7.2 to 8.8 V
      for RHD
      Tester Connection Switch Condition Specified Condition
      f33-4 (PVCC) - f33-3 (GND) Ottoman switch ON 7.2 to 8.8 V

    NG

    REPLACE POSITION CONTROL ECU Click here

    OK

  4. CHECK REAR SEAT ADJUSTER ASSEMBLY (POSITION CONTROL SENSOR)

    A01GNX8E02

    1. for LHD:

      Reconnect the f16 motor connector.

    2. for RHD:

      Reconnect the f33 motor connector.

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

      Standard voltage
      for LHD
      Tester Connection Switch Condition Specified Condition
      f16-2 (SSRO) - Body ground Ottoman switch ON 0 to 8 V
      for RHD
      Tester Connection Switch Condition Specified Condition
      f33-2 (SSRO) - Body ground Ottoman switch ON 0 to 8 V

    NG

    REPLACE REAR SEAT ADJUSTER ASSEMBLY Click here

    OK

  5. CHECK FOR DTC


    1. Clear the DTC Click here.

    2. Recheck the DTC.

      OK
      DTC B2657 is not output.

    NG

    REPLACE POSITION CONTROL ECU Click here

    OK

    END (SYSTEM RETURN TO NORMAL)

  6. INSPECT REAR SEAT ADJUSTER ASSEMBLY (POWER SEAT MOTOR)

    A01GMZQE08

    1. Disconnect the motor connector.

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


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

        OK
        Measurement Condition Operational Direction

        Battery positive (+) → 5

        Battery negative (-) → 1

        		 Upward

        Battery positive (+) → 1

        Battery negative (-) → 5

        		 Downward

    NG

    REPLACE REAR SEAT ADJUSTER ASSEMBLY Click here

    OK

  7. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU - REAR POWER SEAT MOTOR)

    A01GHKRE02

    1. for LHD:


      1. Disconnect the f4 ECU connector.

      2. Disconnect the f16 motor connector.

    2. for RHD


      1. Disconnect the f24 ECU connector.

      2. Disconnect the f33 motor connector.

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

      Standard resistance
      for LHD
      Tester Connection Condition Specified Condition
      f4-4 (OTO+) - f16-5 (ROUP) Always Below 1 Ω
      f4-11 (OTO-) - f16-1 (RODW) Always Below 1 Ω
      for RHD
      Tester Connection Condition Specified Condition
      f24-4 (OTO+) - f33-5 (LOUP) Always Below 1 Ω
      f24-11 (OTO-) - f33-1 (LODW) Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE POSITION CONTROL ECU Click here