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DTC B265B: Lumbar 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 (LUMBAR SLIDE) 
    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
      Lumbar Slide Lumbar sliding operation Front / OFF / Rear -

      OK

      Motor operates normally.

    Result:  NG

    NG 

    See step  6

    Result:  OK

    OK 

    See step  3

  3. CHECK POSITION CONTROL ECU ASSEMBLY (LUMBAR MOTOR CIRCUIT) 
    1. Disconnect the lumbar motor connector.
      GTY524427Courtesy 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
      d31-2 (VCC) - d31-3 (GND) Lumbar switch on 4.8 to 5.1 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Lumbar Support Adjuster Assembly LH [Lumbar Motor])

    Result:  NG

    NG 

    See step  5

    Result:  OK

    OK 

    See step  4

  4. CHECK LUMBAR SUPPORT ADJUSTER ASSEMBLY LH (LUMBAR MOTOR) 
    1. Reconnect the lumbar motor connector.
      GTY538038Courtesy 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
      d31-2 (VCC) - Body ground Lumbar 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
      (Lumbar Support Adjuster Assembly LH [Lumbar 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 LUMBAR SUPPORT ADJUSTER ASSEMBLY LH (LUMBAR MOTOR) 

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

    Result:  D

    D 

    REPLACE LUMBAR SUPPORT ADJUSTER ASSEMBLY LH (LUMBAR MOTOR) 

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

  5. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU ASSEMBLY - LUMBAR SUPPORT ADJUSTER ASSEMBLY 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
      d4-13 (SSLB) - d31-2 (VCC) Always Below 1 Ω
      d5-20 (SGND) - d31-3 (GND) Always Below 1 Ω
      d4-13 (SSLB) - 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 LUMBAR SUPPORT ADJUSTER ASSEMBLY LH (LUMBAR MOTOR) 
    1. Disconnect the d31 lumbar motor connector.
      GTY411281Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check if the lumbar motor moves smoothly when the battery is connected to the lumbar motor connector terminals.

      OK

      Measurement Condition Operational Direction
      Battery positive (+) → 1 (H)
      Battery negative (-) → 4 (R)      		 Forward
      Battery positive (+) → 4 (R)
      Battery negative (-) → 1 (H)      		 Backward
      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
      (Lumbar Support Adjuster Assembly LH [Lumbar Motor])

    Result:  B

    B 

    REPLACE LUMBAR SUPPORT ADJUSTER ASSEMBLY LH (LUMBAR MOTOR) 

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

    Result:  C

    C 

    REPLACE LUMBAR SUPPORT ADJUSTER ASSEMBLY LH (LUMBAR MOTOR) 

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

    Result:  A

    A 

    See step  7

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      d4-5 (L+) - d31-1 (H) Always Below 1 Ω
      d5-3 (L-) - d31-4 (R) Always Below 1 Ω
      d4-5 (L+) - Body ground Always 10 kΩ or higher
      d5-3 (L-) - 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 (LUMBAR SLIDE) 
    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
      Lumbar Slide Lumbar sliding operation Front / OFF / Rear -

      OK

      Motor operates normally.

    Result:  NG

    NG 

    See step  12

    Result:  OK

    OK 

    See step  9

  9. CHECK POSITION CONTROL ECU ASSEMBLY (LUMBAR MOTOR CIRCUIT) 
    1. Disconnect the lumbar motor connector.
      GTY528054Courtesy 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
      c26-2 (VCC) - d26-3 (GND) Lumbar switch on 4.8 to 5.1 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Lumbar Support Adjuster Assembly RH [Lumbar Motor])

    Result:  NG

    NG 

    See step  11

    Result:  OK

    OK 

    See step  10

  10. CHECK LUMBAR SUPPORT ADJUSTER ASSEMBLY RH (LUMBAR MOTOR) 
    1. Reconnect the lumbar motor connector.
      GTY526811Courtesy 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
      c26-2 (VCC) - Body ground Lumbar switch on 4.5 to 4.8 V
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Lumbar Support Adjuster Assembly RH [Lumbar Motor])

    Result:  OK

    OK 

    REPLACE POSITION CONTROL ECU ASSEMBLY 

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

    Result:  NG

    NG 

    REPLACE LUMBAR SUPPORT ADJUSTER ASSEMBLY RH (LUMBAR MOTOR) 

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

  11. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU ASSEMBLY - LUMBAR SUPPORT ADJUSTER ASSEMBLY 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
      c3-13 (SSLB) - c26-2 (VCC) Always Below 1 Ω
      c2-20 (SGND) - c26-3 (GND) Always Below 1 Ω
      c3-13 (SSLB) - 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 LUMBAR SUPPORT ADJUSTER ASSEMBLY RH (LUMBAR MOTOR) 
    1. Disconnect the c26 lumbar motor connector.
      GTY411282Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check if the lumbar motor moves smoothly when the battery is connected to the lumbar motor connector terminals.

      OK

      Measurement Condition Operational Direction
      Battery positive (+) → 1 (H1)
      Battery negative (-) → 4 (R1)      		 Forward
      Battery positive (+) → 4 (R1)
      Battery negative (-) → 1 (H1)      		 Backward
      TEXT IN ILLUSTRATION

      *a Component without harness connected
      (Lumbar Support Adjuster Assembly RH [Lumbar Motor])

    Result:  NG

    NG 

    REPLACE LUMBAR SUPPORT ADJUSTER ASSEMBLY RH (LUMBAR MOTOR) 

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

    Result:  OK

    OK 

    See step  13

  13. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU ASSEMBLY - LUMBAR SUPPORT ADJUSTER ASSEMBLY 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
      c3-5 (L+) - c26-1 (H1) Always Below 1 Ω
      c2-3 (L-) - c26-4 (R1) Always Below 1 Ω
      c3-5 (L+) - Body ground Always 10 kΩ or higher
      c2-3 (L-) - 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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