2008 Lexus IS FFACTORY OEM SERVICE PROCEDURE

Terminals Of Ecu

  1. CHECK MULTIPLEX NETWORK MASTER SWITCH ASSEMBLY 
    1. Disconnect the M7 multiplex network master switch assembly connector
      Fig 1: Identifying M7 Multiplex Network Master Switch Assembly Connector
      G05755719Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance according to the value(s) in the table below.
      TERMINAL DESCRIPTION

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      M7-2 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω
      M7-4 (KL) - M7-2 (GND) L - W-B Key linked power window lock signal Using key, operate driver door lock cylinder to FREE 10 kΩ or higher
      M7-4 (KL) - M7-2 (GND) L - W-B Key linked power window lock signal Using key, operate driver door lock cylinder to LOCK Below 1 Ω
      M7-9 (CPUB) - M7-2 (GND) G - W-B +B power supply Always 11 to 14 V
      M7-10 (BDR) - M7-2 (GND) L - W-B +B power supply Always 11 to 14 V
      M7-14 (KUL) - M7-2 (GND) W - W-B Key linked power window unlock signal Using key, operate driver door lock cylinder to FREE 10 kΩ or higher
      M7-14 (KUL) - M7-2 (GND) W - W-B Key linked power window unlock signal Using key, operate driver door lock cylinder to UNLOCK Below 1 Ω
      M7-20 (SIG) - M7-2 (GND) B - W-B Ignition power supply Engine switch off Below 1 V
      M7-20 (SIG) - M7-2 (GND) B - W-B Ignition power supply Engine switch on (IG) 11 to 14 V

      If the result is not as specified, there may be a malfunction on the wire harness side.

    3. Reconnect the M7 multiplex network master switch assembly connector
    4. Reset the power window regulator motor (See CUSTOMIZE PARAMETERS  )
    5. Measure the voltage according to the value(s) in the table below.
      TERMINAL DESCRIPTION

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      M7-1 (UP) - M7-2 (GND) R - W-B Power window motor UP output Engine switch on (IG), driver side power window switch OFF Below 1 V
      M7-1 (UP) - M7-2 (GND) R - W-B Power window motor UP output Engine switch on (IG), driver side power window switch UP (Manual operation) 11 to 14 V
      M7-1 (UP) - M7-2 (GND) R - W-B Power window motor UP output Engine switch on (IG), driver side power window fully open Below 1 V
      M7-1 (UP) - M7-2 (GND) R - W-B Power window motor UP output Engine switch on (IG), driver side power window switch UP (AUTO operation) 11 to 14 V
      M7-1 (UP) - M7-2 (GND) R - W-B Power window motor UP output Engine switch on (IG), driver side power window fully closed Below 1 V
      M7-4 (KL) - M7-2 (GND) L - W-B Key linked power window lock signal Using key, operate driver door lock cylinder to FREE 11 to 14 V
      M7-4 (KL) - M7-2 (GND) L - W-B Key linked power window lock signal Using key, operate driver door lock cylinder to LOCK Below 1 V
      M7-6 (PWS) - M7-2 (GND) P - W-B Power window lock switch output Engine switch on (IG), power window lock switch UNLOCK 11 to 14 V
      M7-6 (PWS) - M7-2 (GND) P - W-B Power window lock switch output Engine switch on (IG), power window lock switch LOCK Below 1 V
      M7-14 (KUL) - M7-2 (GND) W - W-B Key linked power window unlock signal Using key, operate driver door lock cylinder to FREE 11 to 14 V
      M7-14 (KUL) - M7-2 (GND) W - W-B Key linked power window unlock signal Using key, operate driver door lock cylinder to UNLOCK Below 1 V
      M7-11 (DN) - M7-2 (GND) G - W-B Power window motor DOWN output Engine switch on (IG), driver side power window switch OFF Below 1 V
      M7-11 (DN) - M7-2 (GND) G - W-B Power window motor DOWN output Engine switch on (IG), driver side power window switch DOWN (Manual operation) 11 to 14 V
      M7-11 (DN) - M7-2 (GND) G - W-B Power window motor DOWN output Engine switch on (IG), driver side power window fully closed Below 1 V
      M7-11 (DN) - M7-2 (GND) G - W-B Power window motor DOWN output Engine switch on (IG), driver side power window switch DOWN (AUTO operation) 11 to 14 V
      M7-11 (DN) - M7-2 (GND) G - W-B Power window motor DOWN output Engine switch on (IG), driver side power window fully open Below 1 V
      M7-19 (VCC) - M7-2 (GND) LG - W-B Power window motor power source Engine switch on (IG), driver side power window switch OFF Below 1 V
      M7-19 (VCC) - M7-2 (GND) LG - W-B Power window motor power source Engine switch on (IG), driver side power window switch UP or DOWN 11 to 14 V

      If the result is not as specified, the multiplex network master switch assembly may have a malfunction.

  2. CHECK MULTIPLEX NETWORK SWITCH ASSEMBLY (for Front Passenger Side) 
    1. Disconnect the L13 multiplex network switch assembly connector.
      Fig 2: Identifying L13 Multiplex Network Switch Assembly Connector
      G05755720Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance according to the value(s) in the table below
      TERMINAL DESCRIPTION

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      L13-7 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω
      L13-12 (BDR) - L13-7 (GND) L - W-B +B power supply Always 11 to 14 V

      If the result is not as specified, there may be a malfunction on the wire harness side

    3. Reconnect the L13 multiplex network switch assembly connector
    4. Reset the power window regulator motor (See CUSTOMIZE PARAMETERS  ).
    5. Measure the voltage according to the value(s) in the table below
      TERMINAL DESCRIPTION

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      L13-1 (DN) - L13-7 (GND) G - W-B Power window motor DOWN output Engine switch on (IG), front passenger side power window switch OFF Below 1 V
      L13-1 (DN) - L13-7 (GND) G - W-B Power window motor DOWN output Engine switch on (IG), front passenger side power window switch DOWN (Manual operation) 11 to 14 V
      L13-1 (DN) - L13-7 (GND) G - W-B Power window motor DOWN output Engine switch on (IG), front passenger side power window fully closed Below 1 V
      L13-1 (DN) - L13-7 (GND) G - W-B Power window motor DOWN output Engine switch on (IG), front passenger side power window switch DOWN (AUTO operation) 11 to 14 V
      L13-1 (DN) - L13-7 (GND) G - W-B Power window motor DOWN output Engine switch on (IG), front passenger side power window fully open Below 1 V
      L13-5 (VCC) - L13-8 (SGND) W - L Power window motor power source Engine switch on (IG), front passenger side power window switch OFF Below 1 V
      L13-5 (VCC) - L13-8 (SGND) W - L Power window motor power source Engine switch on (IG), front passenger side power window switch UP or DOWN 11 to 14 V
      L13-6 (UP) - L13-7 (GND) R - W-B Power window motor UP output Engine switch on (IG), front passenger side power window switch OFF Below 1 V
      L13-6 (UP) - L13-7 (GND) R - W-B Power window motor UP output Engine switch on (IG), front passenger side power window switch UP (Manual operation) 11 to 14 V
      L13-6 (UP) - L13-7 (GND) R - W-B Power window motor UP output Engine switch on (IG), front passenger side power window fully open Below 1 V
      L13-6 (UP) - L13-7 (GND) R - W-B Power window motor UP output Engine switch on (IG), front passenger side power window UP (AUTO operation) 11 to 14 V
      L13-6 (UP) - L13-7 (GND) R - W-B Power window motor UP output Engine switch on (IG), front passenger side power window fully closed Below 1 V
      L13-11 (PCT) - L13-7 (GND) P - W-B Power window lock switch output Engine switch on (IG), power window lock switch UNLOCK 11 to 14 V
      L13-11 (PCT) - L13-7 (GND) P - W-B Power window lock switch output Engine switch on (IG), power window lock switch LOCK Below 1 V

      If the result is not as specified, the multiplex network switch assembly may have a malfunction.

  3. CHECK MULTIPLEX NETWORK SWITCH ASSEMBLY (REAR LH) 
    1. Disconnect the O1 multiplex network switch assembly connector
      Fig 3: Identifying O1 Multiplex Network Switch Assembly Connector
      G05755721Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance according to the value(s) in the table below
      TERMINAL DESCRIPTION

      Taster Connection Wiring Color Terminal Description Condition Specified Condition
      O1-7 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω
      O1-10 (SEL2) - O1-7 (GND) W-B - W-B Rear LH side detection signal Always Below 1 Ω
      O1-12 (BDR) - O1-7 (GND) O - W-B +B power supply Always 11 to 14 V

      If the result is not as specified, there may be a malfunction on the wire harness side

    3. Reconnect the O1 multiplex network switch assembly connector.
    4. Reset the power window regulator motor (See CUSTOMIZE PARAMETERS  ).
    5. Measure the voltage according to the value(s) in the table below.
      TERMINAL DESCRIPTION

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      O1-1 (DN) - O1-7 (GND) G - W-B Power window motor DOWN output Engine switch on (IG), rear LH power window switch OFF Below 1 V
      O1-1 (DN) - O1-7 (GND) G - W-B Power window motor DOWN output Engine switch on (IG), rear LH power window switch DOWN (Manual operation) 11 to 14 V
      O1-1 (DN) - O1-7 (GND) G - W-B Power window motor DOWN output Engine switch on (IG), rear LH power window fully closed Below 1 V
      O1-1 (DN) - O1-7 (GND) G - W-B Power window motor DOWN output Engine switch on (IG), rear LH power window switch DOWN (AUTO operation) 11 to 14 V
      O1-1 (DN) - O1-7 (GND) G - W-B Power window motor DOWN output Engine switch on (IG), rear LH power window fully open Below 1 V
      O1-5 (VCC) - O1-8 (SGND) W - LG Power window motor power source Engine switch on (IG), rear LH side power window switch OFF Below 1 V
      O1-5 (VCC) - O1-8 (SGND) W - LG Power window motor power source Engine switch on (IG), rear LH side power window switch UP or DOWN 11 to 14 V
      O1-6 (UP) - O1-7 (GND) R - W-B Power window motor UP output Engine switch on (IG), rear LH power window switch OFF Below 1 V
      O1-6 (UP) - O1-7 (GND) R - W-B Power window motor UP output Engine switch on (IG), rear LH power window switch UP (Manual operation) 11 to 14 V
      O1-6 (UP) - O1-7 (GND) R - W-B Power window motor UP output Engine switch on (IG), rear LH power window fully open Below 1 V
      O1-6 (UP) - O1-7 (GND) R - W-B Power window motor UP output Engine switch on (IG), rear LH power window switch UP (AUTO operation) 11 to 14 V
      O1-6 (UP) - O1-7 (GND) R - W-B Power window motor UP output Engine switch on (IG), rear LH power window fully closed Below 1 V
      O1-11 (PCT1) - O1-7 (GND) V - W-B Power window lock switch output Engine switch on (IG), power window lock switch UNLOCK 11 to 14 V
      O1-11 (PCT1) - O1-7 (GND) V - W-B Power window lock switch output Engine switch on (IG), power window lock switch LOCK Below 1 V

      If the result is not as specified, the multiplex network switch assembly may have a malfunction

  4. CHECK MULTIPLEX NETWORK SWITCH ASSEMBLY (REAR RH) 
    1. Disconnect the N1 multiplex network switch assembly connector.
      Fig 4: Identifying N1 Multiplex Network Switch Assembly Connector
      G05755722Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance according to the value(s) in the table below
      TERMINAL DESCRIPTION

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      N1-7 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω
      N1-9 (SEL1) - N1-7 (GND) W-B - W-B Rear RH side detection signal Always Below 1 Ω
      N1-12 (BDR) - N1-7 (GND) O - W-B +B power supply Always 11 to 14 V

      If the result is not as specified, there may be a malfunction on the wire harness side

    3. Reconnect the N1 multiplex network switch assembly connector.
    4. Reset the power window regulator motor (See CUSTOMIZE PARAMETERS  ).
    5. Measure the voltage according to the value(s) in the table below.
      TERMINAL DESCRIPTION

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      N1-1 (DN) - N1-7 (GND) G - W-B Power window motor DOWN output Engine switch on (IG), rear RH power window switch OFF Below 1 V
      N1-1 (DN) - N1-7 (GND) G - W-B Power window motor DOWN output Engine switch on (IG), rear RH power window switch DOWN (Manual operation) 11 to 14 V
      N1-1 (DN) - N1-7 (GND) G - W-B Power window motor DOWN output Engine switch on (IG), rear RH power window fully closed Below 1 V
      N1-1 (DN) - N1-7 (GND) G - W-B Power window motor DOWN output Engine switch on (IG), rear RH power window switch DOWN (AUTO operation) 11 to 14 V
      N1-1 (DN) - N1-7 (GND) G - W-B Power window motor DOWN output Engine switch on (IG), rear RH power window fully open Below 1 V
      N1-5 (VCC) - N1-8 (SGND) W - LG Power window motor power source Engine switch on (IG), rear RH side power window switch OFF Below 1 V
      N1-5 (VCC) - N1-8 (SGND) W - LG Power window motor power source Engine switch on (IG), rear RH side power window switch UP or DOWN 11 to 14 V
      N1-6 (UP) - N1-7 (GND) R - W-B Power window motor UP output Engine switch on (IG), rear RH power window switch OFF Below 1 V
      N1-6 (UP) - N1-7 (GND) R - W-B Power window motor UP output Engine switch on (IG), rear RH power window switch UP (Manual operation) 11 to 14 V
      N1-6 (UP) - N1-7 (GND) R - W-B Power window motor UP output Engine switch on (IG), rear RH power window fully open Below 1 V
      N1-6 (UP) - N1-7 (GND) R - W-B Power window motor UP output Engine switch on (IG), rear RH power window switch UP (AUTO operation) 11 to 14 V
      N1-6 (UP) - N1-7 (GND) R - W-B Power window motor UP output Engine switch on (IG), rear RH power window fully closed Below 1 V
      N1-11 (PCT1) - N1-7 (GND) P - W-B Power window lock switch output Engine switch on (IG), power window lock switch UNLOCK 11 to 14 V
      N1-11 (PCT1) - N1-7 (GND) P - W-B Power window lock switch output Engine switch on (IG), power window lock switch LOCK Below 1 V

      If the result is not as specified, the multiplex network switch assembly may have a malfunction.

  5. CHECK MAIN BODY ECU RH (COWL SIDE JUNCTION BLOCK RH) 
    1. Disconnect the RK, RN and RD junction block connectors
      Fig 5: Identifying RK, RN And RD Junction Block Connector
      G05755723Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance according to the value(s) in the table below
      TERMINAL DESCRIPTION

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      RK-5 (BECU) - Body ground G-R - Body ground Battery power supply Always 11 to 14 V
      RN-1 (BATB) - Body ground R - Body ground Battery power supply Always 11 to 14 V
      RD-7 (GND2) - Body ground W-B - Body ground Ground Always Below 1 Ω
      RD-17 (GND1) - Body ground W-B - Body ground Ground Always Below 1 Ω

      If the result is not as specified, there may be a malfunction in the wire harness side

    3. Reconnect the RK, RN, and RD junction block connectors
    4. Measure the voltage according to the value(s) in the table below
      TERMINAL DESCRIPTION

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      P1-14 (DCTY) - Body ground W - Body ground Driver side door courtesy switch input Driver side door open Below 1 V
      P1-14 (DCTY) - Body ground W - Body ground Driver side door courtesy switch input Driver side door closed 11 to 14 V
      J75-23 (PCTY) - Body ground B - Body ground Front passenger side door courtesy switch input Front passenger side door open Below 1 V
      J75-23 (PCTY) - Body ground B - Body ground Front passenger side door courtesy switch input Front passenger side door closed 11 to 14 V
      RA-11 (LCTY) - Body ground BR - Body ground Rear door LH courtesy light switch input Rear door LH open Below 1 V
      RA-11 (LCTY) - Body ground BR - Body ground Rear door LH courtesy light switch input Rear LH side door closed 11 to 14 V
      P1-16 (RCTY) - Body ground O - Body ground Rear door RH courtesy light switch input Rear door RH open Below 1 V
      P1-16 (RCTY) - Body ground O - Body ground Rear door RH courtesy light switch input Rear RH side door closed 11 to 14 V
      J75-25 (LGCY) - Body ground L - Body ground Luggage compartment door courtesy light switch input Luggage compartment door open Below 1 V
      J75-25 (LGCY) - Body ground L - Body ground Luggage compartment door courtesy light switch input Luggage compartment door closed 11 to 14 V

      If the result is not as specified, the main body ECU RH (cowl side junction block RH) may have a malfunction

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  • • You are missing required tools, torque specs, or safe lifting equipment.
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