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DTC B2659: Side Support Sensor Circuit [09/2014 - ]: Procedure

  1. CHECK FOR DTC 
    1. Check the parts which the DTCs have been output from (See page. Refer to DTC CHECK / CLEAR [09/2014 - ] ).
      RESULT

      Result Proceed to
      DTC output from "Driver Seat" A
      DTC output from "Passenger Seat" B

    Result:  B

    B 

    See step  8

    Result:  A

    A 

    See step  2

  2. PERFORM ACTIVE TEST USING TECHSTREAM (SIDE SUPPORT OPERATION) 
    1. Turn the power switch off.
    2. Connect the Techstream to the DLC3.
    3. Turn the power switch on (IG).
    4. Turn the Techstream on.
    5. Enter the following menus: Body Electrical / Driver Seat / Active Test.
    6. Perform the Active Test according to the display on the Techstream.
      DRIVER SEAT

      Tester Display Test Part Control Range Diagnostic Note
      Side Support Operation Side support operation Open / OFF / Close -

      OK

      Motor operates normally.

    Result:  NG

    NG 

    See step  6

    Result:  OK

    OK 

    See step  3

  3. CHECK POSITION CONTROL ECU ASSEMBLY (SIDE SUPPORT MOTOR CIRCUIT) 
    1. Disconnect the side support motor connector.
      GTY522407Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      d30-2 (SISR) - d30-3 (ISRE) Side support switch on 4.8 to 5.1 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Front Seat Back Support LH [Side Support Motor])

    Result:  NG

    NG 

    See step  5

    Result:  OK

    OK 

    See step  4

  4. CHECK FRONT SEAT BACK SUPPORT LH (SIDE SUPPORT MOTOR) 
    1. Reconnect the side support motor connector.
      GTY533012Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      d30-2 (SISR) - Body ground Side support switch on 4.5 to 4.8 V
      RESULT

      Result Proceed to
      OK (for Sports Seat Type) A
      OK (for Luxury Seat Type) B
      NG (for Sports Seat Type) C
      NG (for Luxury Seat Type) D
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Front Seat Back Support LH [Side Support Motor])

    Result:  A

    A 

    REPLACE POSITION CONTROL ECU ASSEMBLY 

    (See page. Refer to REMOVAL [09/2014 - ] )

    Result:  B

    B 

    REPLACE POSITION CONTROL ECU ASSEMBLY 

    (See page. Refer to REMOVAL [09/2014 - ] )

    Result:  C

    C 

    REPLACE FRONT SEAT BACK SUPPORT LH (SIDE SUPPORT MOTOR) 

    (See page. Refer to DISASSEMBLY [09/2014 - ] )

    Result:  D

    D 

    REPLACE FRONT SEAT BACK SUPPORT LH (SIDE SUPPORT MOTOR) 

    (See page. Refer to DISASSEMBLY [09/2014 - ] )

  5. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU ASSEMBLY - FRONT SEAT BACK SUPPORT LH) 
    1. Disconnect the d4 and d5 position control ECU assembly connectors.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      d4-16 (SSIR) - d30-2 (SISR) Always Below 1 Ω
      d5-20 (SGND) - d30-3 (ISRE) Always Below 1 Ω
      d4-16 (SSIR) - Body ground Always 10 kΩ or higher
      d5-20 (SGND) - Body ground Always 10 kΩ or higher
      RESULT

      Result Proceed to
      OK (for Sports Seat Type) A
      OK (for Luxury Seat Type) B
      NG C

    Result:  A

    A 

    REPLACE POSITION CONTROL ECU ASSEMBLY 

    (See page. Refer to REMOVAL [09/2014 - ] )

    Result:  B

    B 

    REPLACE POSITION CONTROL ECU ASSEMBLY 

    (See page. Refer to REMOVAL [09/2014 - ] )

    Result:  C

    C 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  6. INSPECT FRONT SEAT BACK SUPPORT LH (SIDE SUPPORT MOTOR) 
    1. Disconnect the d30 side support motor connector.
      GTY411181Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check if the side support motor moves smoothly when the battery is connected to the side support motor connector terminals.

      OK

      Measurement Condition Operational Direction
      Battery positive (+) → 4 (ISR+)
      Battery negative (-) → 1 (ISR-)      		 Paddle Open
      Battery positive (+) → 1 (ISR-)
      Battery negative (-) → 4 (ISR+)      		 Paddle Close
      RESULT

      Result Proceed to
      OK A
      NG (for Sports Seat Type) B
      NG (for Luxury Seat Type) C
      TEXT IN ILLUSTRATION

      *a Component without harness connected
      (Front Seat Back Support LH [Side Support Motor])

    Result:  B

    B 

    REPLACE FRONT SEAT BACK SUPPORT LH (SIDE SUPPORT MOTOR) 

    (See page. Refer to DISASSEMBLY [09/2014 - ] )

    Result:  C

    C 

    REPLACE FRONT SEAT BACK SUPPORT LH (SIDE SUPPORT MOTOR) 

    (See page. Refer to DISASSEMBLY [09/2014 - ] )

    Result:  A

    A 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU ASSEMBLY - FRONT SEAT BACK SUPPORT LH) 
    1. Disconnect the d3 position control ECU assembly connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      d3-3 (ISR+) - d30-4 (ISR+) Always Below 1 Ω
      d3-6 (ISR-) - d30-1 (ISR-) Always Below 1 Ω
      d3-3 (ISR+) - Body ground Always 10 kΩ or higher
      d3-6 (ISR-) - Body ground Always 10 kΩ or higher
      RESULT

      Result Proceed to
      OK (for Sports Seat Type) A
      OK (for Luxury Seat Type) B
      NG C

    Result:  A

    A 

    REPLACE POSITION CONTROL ECU ASSEMBLY 

    (See page. Refer to REMOVAL [09/2014 - ] )

    Result:  B

    B 

    REPLACE POSITION CONTROL ECU ASSEMBLY 

    (See page. Refer to REMOVAL [09/2014 - ] )

    Result:  C

    C 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  8. PERFORM ACTIVE TEST USING TECHSTREAM (SIDE SUPPORT OPERATION) 
    1. Turn the power switch off.
    2. Connect the Techstream to the DLC3.
    3. Turn the power switch on (IG).
    4. Turn the Techstream on.
    5. Enter the following menus: Body Electrical / Passenger Seat / Active Test.
    6. Perform the Active Test according to the display on the Techstream.
      PASSENGER SEAT

      Tester Display Test Part Control Range Diagnostic Note
      Side Support Operation Side support operation Open / OFF / Close -

      OK

      Motor operates normally.

    Result:  NG

    NG 

    See step  12

    Result:  OK

    OK 

    See step  9

  9. CHECK POSITION CONTROL ECU ASSEMBLY (SIDE SUPPORT MOTOR CIRCUIT) 
    1. Disconnect the side support motor connector.
      GTY530547Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      c28-2 (SISR) - c28-3 (ISRG) Side support switch on 4.8 to 5.1 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Front Seat Back Support RH [Side Support Motor])

    Result:  NG

    NG 

    See step  11

    Result:  OK

    OK 

    See step  10

  10. CHECK FRONT SEAT BACK SUPPORT RH (SIDE SUPPORT MOTOR) 
    1. Reconnect the side support motor connector.
      GTY527252Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      c28-2 (SISR) - Body ground Side support switch on 4.5 to 4.8 V
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Front Seat Back Support RH [Side Support Motor])

    Result:  OK

    OK 

    REPLACE POSITION CONTROL ECU ASSEMBLY 

    (See page. Refer to REMOVAL [09/2014 - ] )

    Result:  NG

    NG 

    REPLACE FRONT SEAT BACK SUPPORT RH (SIDE SUPPORT MOTOR) 

    (See page. Refer to DISASSEMBLY [09/2014 - ] )

  11. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU ASSEMBLY - FRONT SEAT BACK SUPPORT RH) 
    1. Disconnect the c2 and c3 position control ECU assembly connectors.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      c3-16 (SSIR) - c28-2 (SISR) Always Below 1 Ω
      c2-20 (SGND) - c28-3 (ISRG) Always Below 1 Ω
      c3-16 (SSIR) - Body ground Always 10 kΩ or higher
      c2-20 (SGND) - Body ground Always 10 kΩ or higher

    Result:  OK

    OK 

    REPLACE POSITION CONTROL ECU ASSEMBLY 

    (See page. Refer to REMOVAL [09/2014 - ] )

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  12. INSPECT FRONT SEAT BACK SUPPORT RH (SIDE SUPPORT MOTOR) 
    1. Disconnect the c28 side support motor connector.
      GTY419291Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check if the side support motor moves smoothly when the battery is connected to the side support motor connector terminals.

      OK

      Measurement Condition Operational Direction
      Battery positive (+) → 4 (ISR+)
      Battery negative (-) → 1 (ISR-)      		 Paddle Open
      Battery positive (+) → 1 (ISR+)
      Battery negative (-) → 4 (ISR-)      		 Paddle Close
      TEXT IN ILLUSTRATION

      *a Component without harness connected
      (Front Seat Back Support RH [Side Support Motor])

    Result:  NG

    NG 

    REPLACE FRONT SEAT BACK SUPPORT RH (SIDE SUPPORT MOTOR) 

    (See page. Refer to DISASSEMBLY [09/2014 - ] )

    Result:  OK

    OK 

    See step  13

  13. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU ASSEMBLY - FRONT SEAT BACK SUPPORT RH) 
    1. Disconnect the c4 position control ECU assembly connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      c4-3 (ISR+) - c28-4 (ISR+) Always Below 1 Ω
      c4-6 (ISR-) - c28-1 (ISR-) Always Below 1 Ω
      c4-3 (ISR+) - Body ground Always 10 kΩ or higher
      c4-6 (ISR-) - Body ground Always 10 kΩ or higher

    Result:  OK

    OK 

    REPLACE POSITION CONTROL ECU ASSEMBLY 

    (See page. Refer to REMOVAL [09/2014 - ] )

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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