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HOMESERVICE MANUALSTOYOTA2013SIENNA LE, AWDREPAIR AND DIAGNOSISACCESSORIES & EQUIPMENTSEATSAUTO ACCESS SEAT SYSTEM (DIAGNOSTIC CODES & SYMPTOM TESTS)AUTO ACCESS SEAT SYSTEMDTC 21: RECLINING PULSE ABNORMALPROCEDURE
2013 Toyota Sienna LE, AWD

DTC 21: Reclining Pulse Abnormal: Procedure

2013 Toyota Sienna LE, AWDSECTION Procedure
  1. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU ASSEMBLY) 
    1. Disconnect the R5 rear seat with adjuster frame assembly LH (reclining motor) connector.
      Fig 1: Identifying R5 LH (Reclining Motor) Connector Terminals
      GTY294788Courtesy 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
      R5-4 - Body ground Power seat switch assembly (up switch) off → on Below 1 V → 11 to 14 V
      No. 2 power seat switch assembly (up switch) off → on Below 1 V → 11 to 14 V
      R5-3 - Body ground Power seat switch assembly (down switch) off → on Below 1 V → 11 to 14 V
      No. 2 power seat switch assembly (down switch) off → on Below 1 V → 11 to 14 V
      R5-5 - Body ground Power seat switch assembly (up or down switch) on
      (During seat reclining operation)      		 5.5 to 6.5 V
      No. 2 power seat switch assembly (up or down switch) on
      (During seat reclining operation)      		 5.5 to 6.5 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Rear Seat with Adjuster Frame Assembly LH (Reclining Motor))
    3. Reconnect the rear seat with adjuster frame assembly LH (reclining motor) connector.

    NG → See step   6 

    OK: Go to next step 

  2. INSPECT REAR SEAT WITH ADJUSTER FRAME ASSEMBLY LH (RECLINING MOTOR) 
    1. Using an oscilloscope, check the waveform.
      Fig 2: Inspecting Rear Seat With Adjuster Frame Assembly LH (Reclining Motor)
      GTY295312Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK

      Tester Connection Switch Condition Specified Condition
      Q3-14 (RCP)- Body ground Power seat switch assembly (up or down switch) on
      (During seat reclining operation)      		 Pulse generation
      No. 2 power seat switch assembly (up or down switch) on
      (During seat reclining operation)      		 Pulse generation
      TEXT IN ILLUSTRATION

      *1 Component with harness connected
      (Position Control ECU Assembly)

    NG → See step   3 

    OK → See step   7 

  3. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU ASSEMBLY - RECLINING MOTOR) 
    1. Disconnect the Q3 position control ECU assembly connector.
    2. Disconnect the R5 rear seat with adjuster frame 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
      Q3-14 (RCP) - R5-2 Always Below 1 Ω
      R5-6 - Body ground Always Below 1 Ω
      Q3-14 (RCP) - Body ground Always 10 kΩ or higher
    4. Reconnect the rear seat with adjuster frame assembly LH (reclining motor) connector.
    5. Reconnect the position control ECU assembly connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  4. REPLACE REAR SEAT WITH ADJUSTER FRAME ASSEMBLY LH (RECLINING MOTOR) 
    1. Temporarily replace the rear seat with adjuster frame assembly (reclining motor) with a new or normally functioning one. Refer to DISASSEMBLY .

    NEXT: Go to next step 

  5. CHECK OPERATION 
    1. Confirm that the auto access seat operates correctly. Refer to OPERATION CHECK .

      OK

      Auto access seat operates correctly.

    NG → See step   8 

    OK → END 

  6. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU ASSEMBLY - RECLINING MOTOR) 
    1. Disconnect the Q3 and Q2 position control ECU assembly connectors.
    2. Disconnect the R5 rear seat with adjuster frame assembly (reclining motor) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      Q3-2 (RCUP) - R5-4 Always Below 1 Ω
      Q3-5 (RCDN) - R5-3 Always Below 1 Ω
      Q2-6 (SP6) - R5-5 Always Below 1 Ω
      Q3-2 (RCUP) - Body ground Always 10 kΩ or higher
      Q3-5 (RCDN) - Body ground Always 10 kΩ or higher
      Q2-6 (SP6) - Body ground Always 10 kΩ or higher
    4. Reconnect the rear seat with adjuster frame assembly (reclining motor) connector.
    5. Reconnect the position control ECU assembly connectors.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   9 

  7. REPLACE POSITION CONTROL ECU ASSEMBLY. Refer to  DISASSEMBLY 
  8. REPLACE POSITION CONTROL ECU ASSEMBLY. Refer to  DISASSEMBLY 
  9. REPLACE POSITION CONTROL ECU ASSEMBLY. Refer to  DISASSEMBLY 
RENDER: 1.0x

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