REAR POWER SEAT CONTROL SYSTEM, Diagnostic DTC:B2657

DTC Code DTC Name
B2657 Ottoman Sensor Malfunction

DESCRIPTION

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

DTC No. Detection Item DTC Detection Condition Trouble Area
B2657 Ottoman Sensor Malfunction The upward and downward lock detection position of the sensor is the same.

  • Position control ECU assembly LH

  • Position control ECU assembly RH

  • Rea No. 2 rear seat adjuster assembly (Ottoman up/down motor)

  • Harness or connector

WIRING DIAGRAM


  1. for Rear Seat RH:

    B006AMTE02

  2. for Rear Seat LH:

    B006AMTE03

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 > Rear Right Seat > Clear DTCs
      Body Electrical > Rear Left Seat > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  2. CHECK FOR DTC


    1. Check for DTCs.

      Click here


      Body Electrical > Rear Right Seat > Trouble Codes
      Body Electrical > Rear Left Seat > Trouble Codes
      OK
      DTC B2657 is not output.
      Result
      Result Proceed to
      DTC B2657 is not output A
      DTC B2657 output from "Rear Right Seat" B
      DTC B2657 output from "Rear Left Seat" C

    A

    USE SIMULATION METHOD TO CHECK Click here

    C

    PERFORM ACTIVE TEST USING GTS (OTTOMAN) Click here

    B

  3. PERFORM ACTIVE TEST USING GTS (OTTOMAN)


    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 / Rear Right Seat / Active Test.

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


      Body Electrical > Rear Right Seat > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Ottoman Ottoman up/down operation OFF/Up/Down -

      Body Electrical > Rear Right Seat > Active Test
      Tester Display
      Ottoman
      OK
      Motor operates normally.
      Result
      Proceed to
      OK
      NG

    NG

    INSPECT REAR NO.2 SEAT ADJUSTER ASSEMBLY (OTTOMAN UP/DOWN MOTOR) Click here

    OK

  4. CHECK POSITION CONTROL ECU ASSEMBLY RH (OTTOMAN MOTOR CIRCUIT)


    1. Disconnect the rear No. 2 seat adjuster assembly (ottoman up/down motor) connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      T15-2 - T15-3 Ottoman switch on 4.8 to 5.1 V
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE REAR NO.2 SEAT ADJUSTER ASSEMBLY Click here

    NG

  5. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU ASSEMBLY RH - REAR NO. 2 SEAT ADJUSTER ASSEMBLY (OTTOMAN UP/DOWN MOTOR))


    1. Disconnect the R7 position control ECU assembly RH connector.

    2. Disconnect the T15 rear No. 2 seat adjuster assembly (ottoman up/down motor) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      R7-27 (SOTG) - T15-2 Always Below 1 Ω
      R7-27 (SOTG) or T15-2 - Other terminals and body ground Always 10 kΩ or higher
      R7-7 (SGND) - T15-3 Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE POSITION CONTROL ECU ASSEMBLY RH Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  6. INSPECT REAR NO.2 SEAT ADJUSTER ASSEMBLY (OTTOMAN UP/DOWN MOTOR)


    1. Remove the rear No. 2 seat adjuster assembly (ottoman up/down motor).

      Click here

    2. Inspect the rear No. 2 seat adjuster assembly (ottoman up/down motor).

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE REAR NO.2 SEAT ADJUSTER ASSEMBLY Click here

    OK

  7. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU ASSEMBLY RH - REAR NO. 2 SEAT ADJUSTER ASSEMBLY (OTTOMAN UP/DOWN MOTOR))


    1. Disconnect the R4 and R5 position control ECU assembly RH connectors.

    2. Disconnect the T15rear No. 2 seat adjuster assembly (ottoman up/down motor) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      R5-8 (OTG+) - T15-4 Always Below 1 Ω
      R5-8 (OTG+) or T15-4 - Other terminals and body ground Always 10 kΩ or higher
      R4-4 (OTG-) - T15-1 Always Below 1 Ω
      R4-4 (OTG-) or T15-1 - Other terminals and body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE POSITION CONTROL ECU ASSEMBLY RH Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  8. PERFORM ACTIVE TEST USING GTS (OTTOMAN)


    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 / Rear left Seat / Active Test.

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


      Body Electrical > Rear Left Seat > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Ottoman Ottoman up/down operation OFF/Up/Down -

      Body Electrical > Rear Left Seat > Active Test
      Tester Display
      Ottoman
      OK
      Motor operates normally.
      Result
      Proceed to
      OK
      NG

    NG

    INSPECT REAR NO.2 SEAT ADJUSTER ASSEMBLY (OTTOMAN UP/DOWN MOTOR) Click here

    OK

  9. CHECK POSITION CONTROL ECU ASSEMBLY RH (OTTOMAN MOTOR CIRCUIT)


    1. Disconnect the rear No. 2 seat adjuster assembly (ottoman up/down motor) connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      T13-2 - T13-3 Ottoman switch on 4.8 to 5.1 V
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE REAR NO.2 SEAT ADJUSTER ASSEMBLY Click here

    NG

  10. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU ASSEMBLY LH - REAR NO. 2 SEAT ADJUSTER ASSEMBLY (OTTOMAN UP/DOWN MOTOR))


    1. Disconnect the R41 position control ECU assembly LH connector.

    2. Disconnect the T13 rear No. 2 seat adjuster assembly (ottoman up/down motor) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      R41-27 (SOTG) - T13-2 Always Below 1 Ω
      R41-27 (SOTG) or T13-2 - Other terminals and body ground Always 10 kΩ or higher
      R41-7 (SGND) - T13-3 Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE POSITION CONTROL ECU ASSEMBLY LH Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  11. INSPECT REAR NO.2 SEAT ADJUSTER ASSEMBLY (OTTOMAN UP/DOWN MOTOR)


    1. Remove the rear No. 2 seat adjuster assembly (ottoman up/down motor).

      Click here

    2. Inspect the rear No. 2 seat adjuster assembly (ottoman up/down motor).

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE REAR NO.2 SEAT ADJUSTER ASSEMBLY Click here

    OK

  12. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU ASSEMBLY LH - REAR NO. 2 SEAT ADJUSTER ASSEMBLY (OTTOMAN UP/DOWN MOTOR))


    1. Disconnect the R38 and R39 position control ECU assembly LH connectors.

    2. Disconnect the T13 rear No. 2 seat adjuster assembly (ottoman up/down motor) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      R39-8 (OTG+) - T13-4 Always Below 1 Ω
      R39-8 (OTG+) or T13-4 - Other terminals and body ground Always 10 kΩ or higher
      R38-4 (OTG-) - T13-1 Always Below 1 Ω
      R38-4 (OTG-) or T13-1 - Other terminals and body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE POSITION CONTROL ECU ASSEMBLY LH Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR