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Home >> Lexus >> 2009 >> IS 250 AWD >> Repair and Diagnosis >> Body & Frame >> Seats >> Front Power Seat Control System (With Memory) (Inspection) >> FRONT POWER SEAT CONTROL SYSTEM (w/ Seat Position Memory System) >> Driver Side Seat Memory Switch Circuit >> Procedure
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Driver Side Seat Memory Switch Circuit: Procedure

  1. READ VALUE USING TECHSTREAM (SEAT MEMORY SWITCH LH) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Read the Data List.
      DRIVER SEAT

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      M3 Switch M3 switch signal / ON or OFF ON: M3 switch is ON
      OFF: M3 switch is OFF      		 -
      M2 Switch M2 switch signal / ON or OFF ON: M2 switch is ON
      OFF: M2 switch is OFF      		 -
      M1 Switch M1 switch signal / ON or OFF ON: M1 switch is ON
      OFF: M1 switch is OFF      		 -
      SET Switch SET switch signal / ON or OFF ON: SET switch is ON
      OFF: SET switch is OFF      		 -

      OK

      On the tester screen, each item changes between ON and OFF according to the above chart.

    NG → Go to next step 

    OK → PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN  PROBLEM SYMPTOMS TABLE  

  2. INSPECT SEAT MEMORY SWITCH LH 
    1. Remove the seat memory switch LH.
      Fig 1: Identifying Seat Memory Switch LH & Connector Terminals
      GTY140208Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Switch Position Specified Condition
      1 (MRY) - 5 E) SET switch is pressed Below 1 Ω
      2 (M1) - 5 (E) M1 switch is pressed Below 1 Ω
      3 (M2) - 5 (E) M2 switch is pressed Below 1 Ω
      4 (M3) - 5 (E) M3 switch is pressed Below 1 Ω
      1 (MRY) - 5 E) SET switch is not pressed 10 kΩ or higher
      2 (M1) - 5 (E) M1 switch is not pressed 10 kΩ or higher
      3 (M2) - 5 (E) M2 switch is not pressed 10 kΩ or higher
      4 (M3) - 5 (E) M3 switch is not pressed 10 kΩ or higher

    NG → REPLACE SEAT MEMORY SWITCH LH 

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (SEAT MEMORY SWITCH LH CIRCUIT) 
    1. Measure the resistance according to the value(s) in the table below.
      Fig 2: Identifying Seat Memory Switch LH Connector Terminals
      GTY120006Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard resistance

      Tester Connection Specified Condition
      M6-2 (M1) - M6-5 (E) 10 kΩ or higher
      M6-3 (M2) - M6-5 (E) 10 kΩ or higher
      M6-4 (M3) - M6-5 (E) 10 kΩ or higher
      M6-1 (MRY) - M6-5 (E) 10 kΩ or higher
      M6-5 (E) - Body ground Below 1 Ω

    NG → Go to next step 

    OK → PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN  PROBLEM SYMPTOMS TABLE  

  4. CHECK HARNESS AND CONNECTOR (OUTER MIRROR CONTROL ECU - SEAT MEMORY SWITCH, BODY GROUND) 
    1. Disconnect the outer mirror control ECU LH connector.
      Fig 3: Identifying Outer Mirror Control ECU & Seat Memory Switch Connector Terminals
      GTY139932Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Specified Condition
      M10-22 (M1) - M6-2 (M1) Below 1 Ω
      M10-23 (M2) - M6-3 (M2) Below 1 Ω
      M10-24 (M3) - M6-4 (M3) Below 1 Ω
      M10-25 (MM) - M6-1 (MRY) Below 1 Ω
      M10-26 (MSWE) - M6-5 (E) Below 1 Ω
      M10-26 (MSWE) - Body ground Below 1 Ω
      M6-5 (E) - Body ground Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → REPLACE OUTER MIRROR CONTROL ECU LH 

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