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Terminals Of Ecu

WARNING: This page is about a different car, the 2008 Lexus IS F. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK POWER SOURCE CONTROL ECU 
    Fig 1: Identifying J55 Connector Terminal
    G05754403Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the J55 ECU connector
    2. Measure the voltage and resistance according to the value (s) in the table below
      VOLTAGE SPECIFICATION

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      J55-6 (GND2) - Body ground W-B - Body ground Ground Always Below 1 Ω
      J55-7 (MPX1) - Body ground GR - Body ground MPX line Always 10 kΩ or higher
      J55-12 (AM2) - Body ground O - Body ground +B power supply Always 11 to 14 V
      J55-14 (SSW1) - Body ground B - Body ground Engine switch signal Engine switch pushed Below 1 Ω
      J55-14 (SSW1) - Body ground B - Body ground Engine switch signal Engine switch not pushed 10 kΩ or higher
      J55-24 (MPX2) - Body ground GR - Body ground MPX line Always 10 kΩ or higher
      J55-30 (LIN1) - Body ground V - Body ground LIN line Always 10 kΩ or higher
      J55-33 (AM1) - Body ground O - Body ground +B power supply Always 11 to 14 V
      J55-37 (SSW2) - Body ground SB - Body ground Engine switch signal Engine switch pushed Below 1 Ω
      J55-37 (SSW2) - Body ground SB - Body ground Engine switch signal Engine switch not pushed 10 kΩ or higher

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

    3. Reconnect the J55 ECU connector
    4. Measure the voltage according to the value (s) in the table below
      VOLTAGE SPECIFICATION

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      J55-1 (STP) - J55-6 (GND2) R - W-B Stop light signal Brake pedal depressed 8 to 14 V
      J55-1 (STP) - J55-6 (GND2) R - W-B Stop light signal Brake pedal released Below 1 V
      J55-2 (TACH) - J55-6 (GND2) W - W-B Tachometer signal Engine running Pulse generation (See  2waveform 2)
      J55-4 (INDS) - J55-6 (GND2) L - W-B Vehicle condition signal Brake pedal depressed, shift lever in P 8 to 14 V
      J55-5 (P) - J55-6 (GND2) BR - W-B Shift lock signal Shift lever in P 8 to 14 V
      J55-5 (P) - J55-6 (GND2) BR - W-B Shift lock signal Shift lever not in P Below 1 V
      J55-11 (ACCD) - J55-6 (GND2) LG - W-B ACC signal Engine switch on (ACC) 8 to 14 V
      J55-11 (ACCD) - J55-6 (GND2) LG - W-B ACC signal Engine switch off Below 1 V
      J55-13 (INDW) - J55-6 (GND2) BR - W-B Warning signal Brake pedal depressed, shift lever in P position, engine switch on (ACC, IG) 8 to 14 V
      J55-15 (STR2) - J55-6 (GND2) V - W-B Starter signal Brake pedal depressed, shift lever in P or N, engine switch on (ST) 8 to 14 V(2)
      J55-17 (STR1) - J55-6 (GND2) SB - W-B Park/neutral position switch Shift lever in P or N Below 1 V
      J55-19 (SPD) - J55-6 (GND2) P - W-B Vehicle speed signal Engine switch on (IG), rotate rear wheel slowly Pulse generation (See  1waveform 1)
      J55-26 (SLP) - J55-6 (GND2) R - W-B Steering lock actuator position signal Steering lock is released Pulse generation (See  3waveform 3)
      J55-26 (SLP) - J55-6 (GND2) R - W-B Steering lock actuator position signal Steering lock is locked Pulse generation (See  3waveform 3)
      J55-28 (SKSW) - J55-6 (GND2) B - W-B Key in vehicle signal Engine switch on (ACC, IG) Below 1 V
      J55-31 (CTSW) - J55-6 (GND2) LG - W-B Starter assist signal Brake pedal depressed, shift lever in P, engine switch is pushed once → on (IG) 0 1 to 0 8 V(1) → 11 to 14 V
      J55-32 (SLR+) - J55-6 (GND2) W - W-B Steering lock motor signal Steering lock motor operating Below 1 V
      J55-32 (SLR+) - J55-6 (GND2) W - W-B Steering lock motor signal Steering lock motor does not operate 11 to 14 V
      J55-34 (IG1D) - J55-6 (GND2) P - W-B IG1 signal Engine switch on (IG) 8 to 14 V
      J55-34 (IG1D) - J55-6 (GND2) P - W-B IG1 signal Engine switch on (ACC) Below 1 V
      J55-35 (IG2D) - J55-6 (J55-6) LG - W-B IG2 signal Engine switch on (IG) 8 to 14 V
      J55-35 (IG2D) - J55-6 (GND2) LG - W-B IG2 signal Engine switch on (ACC) Below 1 V
      J55-36 (SWIL) - J55-6 (GND2) Y - W-B Illumination signal Light control switch TAIL or HEAD 8 to 14 V
      J55-39 (STSW) - J55-6 (GND2) L - W-B Starter activation request signal Brake pedal depressed, engine switch hold on (ST) 8 to 14 V(2)
      (1) Voltage is output only when the engine is cranking.
      (2) Voltage is output for 0 3 seconds when engine is cranking start Disconnect the A5 connector from the ECM before measuring the voltage

      If the result is not as specified, the ECU may have a malfunction.

    5. Using an oscilloscope, check the signal waveform of the ECU
      1. Waveform 1

        Waveform 1 (Reference) 

        WAVEFORM REFERENCE

        Tester Connection J55-19- Body ground
        Tool Setting 5V/DIV, 10ms/DIV
        Vehicle Condition Driving at approx 20 km/h (12 mph)
        Fig 2: Identifying Waveform 1
        G04975562Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        HINT

        As the engine revolution speed increases, the wavelength shortens

      2. Waveform 2

        Waveform 2 (Reference) 

        WAVEFORM REFERENCE

        Tester Connection J55-2 - Body ground
        Tool Setting 5V/DIV, 10ms/DIV
        Vehicle Condition Engine idling
        Fig 3: Identifying Waveform 2
        G04975563Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        HINT

        As the vehicle speed increases, the wavelength shortens

      3. Waveform 3

        Waveform 3 (Reference) 

        WAVEFORM REFERENCE

        Tester Connection J55-26 - Body ground
        Tool Setting 2V/DIV, 100ms/DIV
        Vehicle Condition Steering lock / unlock

        HINT

        As the steering lock increases, the wavelength shortens

        Fig 4: Identifying Waveform 3
        G04975564Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 
    Fig 5: Identifying ECM Connector Terminal
    G05754407Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the P33 ECU connector.
    2. Measure the voltage and resistance according to the value (s) in the table below
      VOLTAGE SPECIFICATION

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      P33-1 (+B1) - Body ground L - Body ground +B power supply Always 11 to 14 V
      P33-10 (LIN) - Body ground V - Body ground LIN line Always 10 kΩ or higher
      P33-17 (E) - Body ground W-B - Body ground Ground Always Below 1 Ω

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

  3. CHECK ECM 
    Fig 6: Identifying ECM Connector Terminal
    G05754408Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A5, E3, E4, E5 and E6 ECM connectors
    2. Measure the voltage and resistance according to the value (s) in the table below
      VOLTAGE SPECIFICATION

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      E5-1 (E02) - Body ground W-B - Body ground Ground Always Below 1 Ω
      E5-2 (E01) - Body ground W-B - Body ground Ground Always Below 1 Ω
      A5-2 (EC) - Body ground W-B - Body ground Ground Always Below 1 Ω
      A5-5 (+B2) - Body ground B-R - Body ground Power source of ECM Engine switch on (IG) 11 to 14 V
      A5-6 (+B) - Body ground B-R - Body ground Power source of ECM Engine switch on (IG) 11 to 14 V
      A5-17 (IGSW) - Body ground B - W - Body ground Ignition switch signal Engine switch on (IG) 11 to 14V
      E3-4 (ME01) - Body ground W-B - Body ground Ground Always Below 1 Ω
      E3-6 (E03) - Body ground W-B - Body ground Ground Always Below 1 Ω
      E4-7 (E1) - Body ground W-B - Body ground Ground Always Below 1 Ω
      E6-3 (E05) - Body ground W-B - Body ground Ground Always Below 1 Ω
      E6-5 (E04) - Body ground W-B - Body ground Ground Always Below 1 Ω

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

    3. Reconnect the A5, E3, E4, E5 and E6 ECM connectors
    4. Measure the voltage according to the value (s) in the table below
      VOLTAGE SPECIFICATION

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      A5-11 (ACCR) - E4-7 (E1) W-L - W-B ACC relay cut signal (output) Engine switch on (IG) 11 to 14 V
      A5-12 (STA) - E4-7 (E1) L-R - W-B Starter relay operation signal Cranking 11 to 14 V
      A5-31 (KSW) - E4-7 (E1) L-R - W-B Engine switch signal (input) Engine switch off 4 to 6 V
      A5-31 (KSW) - E4-7 (E1) L-R - W-B Engine switch signal (input) When engine switch is pushed once 11 to 14 V
      A5-31 (KSW) - E4-7 (E1) L-R - W-B Engine switch signal (input) Engine switch on (ACC) Below 1 5 V
      A6-4 (STP) - E4-7 (E1) R-B - W-B Stop light switch signal (input) Brake pedal depressed 7 5 to 14 V
      A6-4 (STP) - E4-7 (E1) R-B - W-B Stop light switch signal (input) Brake pedal released Below 1 5 V
      A6-16 (TACH) - E4-7 (E1) R-W - W-B Engine revolution signal (output) Idling Pulse generation (see WAVEFORM REFERENCE waveform 1)
      E4-4 (STAR) - E4-7 (E1) L-Y - W-B PNP switch signal (input) Engine switch on (IG), shift position P or N 11 to 14 V

      If the result is not as specified, the ECM may have a malfunction

    5. Using an oscilloscope, check the signal waveform of the ECM

      Waveform 1 (Reference) 

      WAVEFORM REFERENCE

      Tester Connection A6-16 (TACH) - E4-7 (E1)
      Tool Setting 5V/DIV, 10ms/DIV
      Vehicle Condition Engine idling

      HINT

      As the vehicle speed increases, the wavelength shortens.

      Fig 7: Identifying Waveform 1
      G04975563Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. CHECK STEERING LOCK ECU 
    Fig 8: Identifying J29 Connector Terminal
    G05754410Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the J29 ECU connector
    2. Measure the voltage and resistance according to the value (s) in the table below.
      VOLTAGE SPECIFICATION

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      J29-1 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω
      J29-2 (SGND) - Body ground W-B - Body ground Ground Always Below 1 Ω
      J29-6 (IG2) - Body ground LG - Body ground Ignition power supply Engine switch on (IG) 11 to 14 V
      J29-6 (IG2) - Body ground LG - Body ground Ignition power supply Engine switch off Below 1 V
      J29-7 (B) - Body ground O - Body ground +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 J29 ECU connector
    4. Measure the voltage according to the value (s) in the table below.
      VOLTAGE SPECIFICATION

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      J29-4 (SLP1) - J29-1 (GND) R - W-B Steering lock actuator position signal Steering is locked 11 to 14 V
      J29-4 (SLP1) - J29-1 (GND) R - W-B Steering lock actuator position signal Steering is released Below 1 V

      If the result is not as specified, the ECU may have a malfunction

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