FRONT POWER SEAT CONTROL SYSTEM, Diagnostic DTC:B2651

DTC Code DTC Name
B2651 Reclining Sensor Malfunction

DESCRIPTION

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

DTC No. Detection Item DTC Detection Condition Trouble Area
B2651 Reclining Sensor Malfunction The forward and rearward lock detection position of the sensor is the same.

  • Position control ECU assembly

  • No. 2 position control ECU assembly

  • Front seatback frame sub-assembly LH (reclining motor)

  • Front seatback frame sub-assembly RH (reclining motor)

  • Harness or connector

WIRING DIAGRAM


  1. for Driver Seat:

    Figure 1. for LHD:

    B006AMTE11
    *a Reclining Motor
    *b No. 2 Position Control ECU Assembly
    *c Front Seatback Frame Sub-assembly LH

    Figure 2. for RHD:

    B006AMTE12
    *a Reclining Motor
    *b Position Control ECU Assembly
    *c Front Seatback Frame Sub-assembly RH

  2. for Front Passenger Seat:

    Figure 3. for LHD:

    B006AMTE13
    *a Reclining Motor
    *b No. 2 Position Control ECU Assembly
    *c Front Seatback Frame Sub-assembly RH

    Figure 4. for RHD:

    B006AMTE11
    *a Reclining Motor
    *b No. 2 Position Control ECU Assembly
    *c Front Seatback Frame Sub-assembly LH

CAUTION / NOTICE / HINT

Note

Initializing the position control ECU assembly will clear the seat position memory.

Tech Tips


  • Make sure to initialize the position control ECU assembly after replacing the seat assembly or any related parts (including removal and installation).

  • Before initializing the seat ECU, make sure that the D/C CUT fuse is normal.

  • When any of the following conditions are met, the seat position Information in the position control ECU assembly will be cleared.


    • The engine switch is turned off with any of the seat switches being operated and the D/C CUT fuse removed.

    • The engine switch is turned off within 1 second of any of the seat switches being operated with the D/C CUT fuse removed.

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTCs.

      Click here


      Body Electrical > Driver Seat > Clear DTCs
      Body Electrical > Passenger Seat > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  2. CHECK FOR DTC


    1. Check for DTCs.

      Click here


      Body Electrical > Driver Seat > Trouble Codes
      Body Electrical > Passenger Seat > Trouble Codes
      OK
      DTC B2651 is not output.
      Result
      Result Proceed to
      DTC B2651 is not output A
      DTC B2651 output from "Driver Seat" B
      DTC B2651 output from "Front Passenger Seat" C

    A

    USE SIMULATION METHOD TO CHECK Click here

    C

    PERFORM ACTIVE TEST USING GTS (SEAT RECLINING) Click here

    B

  3. PERFORM ACTIVE TEST USING GTS (SEAT RECLINING)


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Driver Seat / Active Test.

    5. Perform the Active Test according to the display on the GTS.


      Body Electrical > Driver Seat > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Seat Reclining Seat reclining operation OFF/Rear/Front -

      Body Electrical > Driver Seat > Active Test
      Tester Display
      Seat Reclining
      OK
      Motor operates normally.
      Result
      Proceed to
      OK
      NG

    NG

    INSPECT FRONT SEATBACK FRAME SUB-ASSEMBLY (RECLINING MOTOR) Click here

    OK

  4. CHECK POSITION CONTROL ECU ASSEMBLY (RECLINING MOTOR CIRCUIT)


    1. for LHD:


      1. Disconnect the front seatback frame sub-assembly LH (reclining motor) connector.

      2. Measure the voltage according to the value(s) in the table below.

        Standard Voltage
        Tester Connection Switch Condition Specified Condition
        S15-2 - S15-3 Reclining switch on 4.8 to 5.1 V

    2. for RHD:


      1. Disconnect the front seatback frame sub-assembly RH (reclining motor) connector.

      2. Measure the voltage according to the value(s) in the table below.

        Standard Voltage
        Tester Connection Switch Condition Specified Condition
        S1-2 - S1-3 Reclining switch on 4.8 to 5.1 V
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE FRONT SEATBACK FRAME SUB-ASSEMBLY Click here

    NG

  5. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU ASSEMBLY - FRONT SEATBACK FRAME SUB-ASSEMBLY (RECLINING MOTOR))


    1. for LHD:


      1. Disconnect the Q28 position control ECU assembly connector.

      2. Disconnect the S15 front seatback frame sub-assembly LH (reclining motor) connector.

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        Q28-24 (SSRR) - S15-2 Always Below 1 Ω
        Q28-24 (SSRR) or S15-2 - Other terminals and body ground Always 10 kΩ or higher
        Q28-16 (SGND) - S15-3 Always Below 1 Ω

    2. for RHD:


      1. Disconnect the Q8 position control ECU assembly connector.

      2. Disconnect the S1 front seatback frame sub-assembly RH (reclining motor) connector.

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        Q8-24 (SSRR) - S1-2 Always Below 1 Ω
        Q8-24 (SSRR) or S1-2 - Other terminals and body ground Always 10 kΩ or higher
        Q8-16 (SGND) - S1-3 Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE POSITION CONTROL ECU ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  6. INSPECT FRONT SEATBACK FRAME SUB-ASSEMBLY (RECLINING MOTOR)


    1. Remove the front seatback frame sub-assembly.

      Click here

    2. Inspect the front seatback frame sub-assembly (reclining motor).

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FRONT SEATBACK FRAME SUB-ASSEMBLY Click here

    OK

  7. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU ASSEMBLY - FRONT SEATBACK FRAME SUB-ASSEMBLY (RECLINING MOTOR))


    1. for LHD:


      1. Disconnect the Q26 position control ECU assembly connector.

      2. Disconnect the S15 front seatback frame sub-assembly LH (reclining motor) connector.

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        Q26-8 (RCL+) - S15-1 Always Below 1 Ω
        Q26-8 (RCL+) or S15-1 - Other terminals and body ground Always 10 kΩ or higher
        Q26-5 (RCL-) - S15-4 Always Below 1 Ω
        Q26-5 (RCL-) or S15-4 - Other terminals and body ground Always 10 kΩ or higher

    2. for RHD:


      1. Disconnect the Q6 position control ECU assembly connector.

      2. Disconnect the S1 front seatback frame sub-assembly RH (reclining motor) connector.

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        Q6-8 (RCL+) - S1-1 Always Below 1 Ω
        Q6-8 (RCL+) or S1-1 - Other terminals and body ground Always 10 kΩ or higher
        Q6-5 (RCL-) - S1-4 Always Below 1 Ω
        Q6-5 (RCL-) or S1-4 - Other terminals and body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE POSITION CONTROL ECU ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  8. PERFORM ACTIVE TEST USING GTS (SEAT RECLINING)


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Passenger Seat / Active Test.

    5. Perform the Active Test according to the display on the GTS.


      Body Electrical > Passenger Seat > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Seat Reclining Seat reclining operation OFF/Rear/Front -

      Body Electrical > Passenger Seat > Active Test
      Tester Display
      Seat Reclining
      OK
      Motor operates normally.
      Result
      Proceed to
      OK
      NG

    NG

    INSPECT FRONT SEATBACK FRAME SUB-ASSEMBLY (RECLINING MOTOR) Click here

    OK

  9. CHECK NO. 2 POSITION CONTROL ECU ASSEMBLY (RECLINING MOTOR CIRCUIT)


    1. for LHD:


      1. Disconnect the front seatback frame sub-assembly RH (reclining motor) connector.

      2. Measure the voltage according to the value(s) in the table below.

        Standard Voltage
        Tester Connection Switch Condition Specified Condition
        S1-2 - S1-3 Reclining switch on 4.8 to 5.1 V

    2. for RHD:


      1. Disconnect the front seatback frame sub-assembly LH (reclining motor) connector.

      2. Measure the voltage according to the value(s) in the table below.

        Standard Voltage
        Tester Connection Switch Condition Specified Condition
        S15-2 - S15-3 Reclining switch on 4.8 to 5.1 V
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE FRONT SEATBACK FRAME SUB-ASSEMBLY Click here

    NG

  10. CHECK HARNESS AND CONNECTOR (NO. 2 POSITION CONTROL ECU ASSEMBLY - FRONT SEATBACK FRAME SUB-ASSEMBLY (RECLINING MOTOR))


    1. for LHD:


      1. Disconnect the Q8 No. 2 position control ECU assembly connector.

      2. Disconnect the S1 front seatback frame sub-assembly RH (reclining motor) connector.

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        Q8-24 (SSRR) - S1-2 Always Below 1 Ω
        Q8-24 (SSRR) or S1-2 - Other terminals and body ground Always 10 kΩ or higher
        Q8-16 (SGND) - S1-3 Always Below 1 Ω

    2. for RHD:


      1. Disconnect the Q28 No. 2 position control ECU assembly connector.

      2. Disconnect the S15 front seatback frame sub-assembly LH (reclining motor) connector.

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        Q28-24 (SSRR) - S15-2 Always Below 1 Ω
        Q28-24 (SSRR) or S15-2 - Other terminals and body ground Always 10 kΩ or higher
        Q28-16 (SGND) - S15-3 Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE NO. 2 POSITION CONTROL ECU ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  11. INSPECT FRONT SEATBACK FRAME SUB-ASSEMBLY (RECLINING MOTOR)


    1. Remove the front seatback frame sub-assembly.

      Click here

    2. Inspect the front seatback frame sub-assembly (reclining motor).

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FRONT SEATBACK FRAME SUB-ASSEMBLY Click here

    OK

  12. CHECK HARNESS AND CONNECTOR (NO. 2 POSITION CONTROL ECU ASSEMBLY - FRONT SEATBACK FRAME SUB-ASSEMBLY (RECLINING MOTOR))


    1. for LHD:


      1. Disconnect the Q6 No. 2 position control ECU assembly connector.

      2. Disconnect the S1 front seatback frame sub-assembly RH (reclining motor) connector.

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        Q6-8 (RCL+) - S1-1 Always Below 1 Ω
        Q6-8 (RCL+) or S1-1 - Other terminals and body ground Always 10 kΩ or higher
        Q6-5 (RCL-) - S1-4 Always Below 1 Ω
        Q6-5 (RCL-) or S1-4 - Other terminals and body ground Always 10 kΩ or higher

    2. for RHD:


      1. Disconnect the Q26 position control ECU assembly connector.

      2. Disconnect the S15 front seatback frame sub-assembly LH (reclining motor) connector.

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        Q26-8 (RCL+) - S15-1 Always Below 1 Ω
        Q26-8 (RCL+) or S15-1 - Other terminals and body ground Always 10 kΩ or higher
        Q26-5 (RCL-) - S15-4 Always Below 1 Ω
        Q26-5 (RCL-) or S15-4 - Other terminals and body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE NO. 2 POSITION CONTROL ECU ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR