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Terminals Of Ecu

WARNING: This page is about a different car, the 2012 Toyota Corolla. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK MAIN BODY ECU (INSTRUMENT PANEL JUNCTION BLOCK) 
    Fig 1: Main Body ECU (Instrument Panel Junction Block) Connector Terminal Identification (1 Of 2)
    GTY197839Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    Fig 2: Main Body ECU (Instrument Panel Junction Block) Connector Terminal Identification (2 Of 2)
    GTY197840Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E50, E51, E52, 2E and 2C ECU connectors.
    2. Measure the voltage and resistance of the wire harness side connector.
      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      E51-1 (AM1) - Body ground L - Body ground +B power supply Always 11 to 14 V
      E50-6 (AM2) - Body ground L - Body ground +B power supply Always 11 to 14 V
      E51-9 (SSW2) - Body ground R - Body ground Engine switch signal Engine switch pushed Below 1 Ω
      E51-9 (SSW2) - Body ground R - Body ground Engine switch signal Engine switch not pushed 10 kΩ or higher
      E51-10 (SSW1) - Body ground W - Body ground Engine switch signal Engine switch pushed Below 1 Ω
      E51-10 (SSW1) - Body ground W - Body ground Engine switch signal Engine switch not pushed 10 kΩ or higher
      E51-4 (GND2) - Body ground W-B - Body ground Ground Always Below 1 Ω
      E52-15 (CANH) - Body ground R - Body ground CAN Line Always 10 kΩ or higher
      E52-16 (CANL) - Body ground W - Body ground CAN Line Always 10 kΩ or higher
      E51-12 (CANN) - Body ground W - Body ground CAN Line Always 10 kΩ or higher
      E51-11 (CANP) - Body ground R - Body ground CAN Line Always 10 kΩ or higher
      2E-17 (GND1) - Body ground W-B - Body ground Ground Always Below 1 Ω
      2C-12 (LIN1) - Body ground V - Body ground LIN line Always 10 kΩ or higher

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

    3. Reconnect the ECU connectors.
    4. Measure the voltage of the connector.
      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      E52-11 (ACCR) - E51-4 (GND2) P - W-B Starter assist signal
      (ACC cut signal)      		 Brake pedal depressed, shift lever P, engine switch is pushed once → on (IG) 0.1 to 0.8 V*1
      → Output voltage at terminal AM1 or AM2 is -2 V or more.
      E51-5 (IG2D) - E51-4 (GND2) BR - W-B IG2 signal Engine switch on (IG) Output voltage at terminal AM1 or AM2 is -2 V or more.
      E51-5 (IG2D) - E51-4 (GND2) BR - W-B IG2 signal Engine switch on (ACC) Below 1 V
      E51-6 (IG1D) - E51-4 (GND2) G - W-B IG1 signal Engine switch on (IG) Output voltage at terminal AM1 or AM2 is -2 V or more.
      E51-6 (IG1D) - E51-4 (GND2) G - W-B IG1 signal Engine switch on (ACC) Below 1 V
      E52-3 (STR) - E51-4 (GND2) W - W-B Park/Neutral position switch signal Engine switch on (IG), shift lever except P or N → P or N Below 2 V → Pulse generation*3
      E50-18 (SLP) - E51-4 (GND2) BR - W-B Steering lock actuator position signal Steering lock is locked Pulse generation
      (See waveform 3)
      E50-18 (SLP) - E51-4 (GND2) BR - W-B Steering lock actuator position signal Steering lock is released Pulse generation
      (See waveform 3)
      E50-7 (SLR+) - E51-4 (GND2) LG - W-B Steering lock motor signal Steering lock motor operating Below 1 V
      E50-7 (SLR+) - E51-4 (GND2) LG - W-B Steering lock motor signal Steering lock motor does not operate Output voltage at terminal AM1 or AM2 is -2 V or more.
      E50-4 (ACCD) - E51-4 (GND2) GR - W-B ACC signal Engine switch on (ACC) Output voltage at terminal AM1 or AM2 is -2 V or more.
      E50-4 (ACCD) - E51-4 (GND2) GR - W-B ACC signal Engine switch off Below 1 V
      E51-8 (SWIL) - E51-4 (GND2) L - W-B Illumination signal Light control switch TAIL or HEAD Output voltage at terminal AM1 or AM2 is -2 V or more.
      E52-2 (TACH) - E51-4 (GND2) GR - W-B Tachometer signal Engine running Pulse generation
      (See waveform 2)
      2C-8 (SPD) - E51-4 (GND2) V - W-B Vehicle speed signal Engine switch on (IG), rotate rear wheel slowly Pulse generation
      (See waveform 1)
      E52-4 (STSW) - E51-4 (GND2) B - W-B Starter activation request signal Brake pedal depressed, engine switch held on (ST) Output voltage at terminal AM1 or AM2 is -2 V or more.
      E52-14 (STR2) - E51-4 (GND2) Y - W-B Starter signal (Sub) Brake pedal depressed, shift lever P or N, engine switch on (ST) Output voltage at terminal AM1 or AM2 is -3.5 V or more.*2
      2F-5 (ACC) - Body ground L - Body ground ACC power supply Always 11 to 14 V
      2G-1 (IG) - Body ground W - Body ground IG power supply Always 11 to 14 V
      E50-14 (STP) - E51-4 (GND2) L - W-B Stop light signal Brake pedal depressed Output voltage at terminal AM1 or AM2 is -2 V or more.
      E50-14 (STP) - E51-4 (GND2) L - W-B Stop light signal Brake pedal released Below 1 V

      HINT: 

      *1: Voltage is output only when the engine is cranking.

      *2: Voltage is output for 0.3 seconds when the engine is cranking to start. Disconnect the B31 connector from the ECM and starter cut relay before measuring the voltage.

      *3: Remove the starter cut relay 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
        Fig 3: Identifying Waveform 1
        GTY138951Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        WAVEFORM 1 (REFERENCE)

        Terminal No. 2C-8 (SPD) - E51-4 (GND2)
        Tool Setting 5 V/DIV., 10 ms./DIV.
        Vehicle Condition Driving at approx. 20 km/h (12 mph)

        HINT: 

        As the vehicle speed increases, the wavelength shortens.

      2. Waveform 2
        Fig 4: Identifying Waveform 2
        GTY121939Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        WAVEFORM 2 (REFERENCE)

        Terminal No. E52-2 (TACH) - E51-4 (GND2)
        Tool Setting 5 V/DIV., 10 ms./DIV.
        Vehicle Condition Engine idling

        HINT: 

        As the engine revolution speed increases, the wavelength shortens.

      3. Waveform 3
        Fig 5: Identifying Waveform 3
        GTY131752Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        WAVEFORM 3 (REFERENCE)

        Terminal No. E50-18 (SLP) - E51-4 (GND2)
        Tool Setting 2 V/DIV., 100 ms./DIV.
        Vehicle Condition Steering lock/unlock
  2. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 
    Fig 6: Certification ECU E36 Connector Terminals Identification
    GTY195990Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E36 ECU connector.
    2. Measure the voltage and resistance of the wire harness side connector.
      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      E36-1 (+B) - Body ground GR - Body ground +B power supply Always 11 to 14 V
      E36-10 (LIN) - Body ground V - Body ground LIN line Always 10 kΩ or higher
      E36-17 (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. Reconnect the ECU connector.
    4. Measure the voltage of the connector.
      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      E36-18 (IG) - Body ground B - Body ground Ignition power supply Engine switch on (IG) 11 to 14 V
      E36-18 (IG) - Body ground B - Body ground Ignition power supply Engine switch off Below 1 V

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

  3. CHECK ECM 
    Fig 7: B31 And A50 ECM Connector Terminals Identification
    GTY191812Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the B31 and A50 ECM connectors.
    2. Measure the voltage and resistance of the wire harness side connectors.
      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      A50-1 (+B2) - Body ground B - Body ground Power source of ECM Engine switch on (IG) 11 to 14 V
      A50-2 (+B) - Body ground B - Body ground Power source of ECM Engine switch on (IG) 11 to 14 V
      A50-27 (IGSW) - Body ground B - Body ground Engine switch signal Engine switch on (IG) 11 to 14 V
      B31-44 (ME01) - Body ground W-B - Body ground Ground Always Below 1 Ω
      B31-45 (E02) - Body ground W-B - Body ground Ground Always Below 1 Ω
      B31-46 (E01) - Body ground W-B - Body ground Ground Always Below 1 Ω
      B31-41 (E04) - Body ground W-B - Body ground Ground Always Below 1 Ω
      A50-32 (EC) - Body ground W-B - Body ground Ground Always Below 1 Ω
      B31-105 (E1) - Body ground BR - Body ground Ground Always Below 1 Ω
      B31-81 (E03) - Body ground W-B - Body ground Ground Always Below 1 Ω
    3. Reconnect the ECM connectors.
    4. Measure the voltage of the connectors.
      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      A50-13 (ACCR) - B31-105 (E1) L-Y - BR ACC relay cut signal (output) Brake pedal depressed, shift lever P or N, engine switch is pushed once → on (IG) 0.1 to 0.8 V* → Output voltage at terminal AM1 or AM2 is -2 V or more.
      A50-14 (STSW) - B31-105 (E1) W-G - BR Starter activation request signal Brake pedal depressed, engine switch held (IG) Output voltage at terminal AM1 or AM2 is -2 V or more.
      A50-15 (TACH) - B31-105 (E1) GR - BR Engine revolution signal (output) Idling Pulse generation (see waveform 1)
      A50-36 (STP) - B31-105 (E1) L - BR Stop light switch signal (input) Brake pedal depressed 7.5 to 14 V
      A50-36 (STP) - B31-105 (E1) L - BR Stop light switch signal (input) Brake pedal released Below 1.5 V
      A50-48 (STA) - B31-105 (E1) LG - BR Starter relay operation signal Cranking 11 to 14 V
      A50-25 (STAR) - B31-105 (E1) W - BR Starter signal (Main) Brake pedal depressed, shift lever P or N, engine switch on (ST) 11 to 14 V

      HINT: 

      *: Voltage is output only when the engine is cranking.

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

    5. Using an oscilloscope, check the signal waveform of the ECM.
      Fig 8: Identifying Waveform 1
      GTY121939Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      WAVEFORM 1 (REFERENCE)

      Terminal No. A50-15 (TACH) - B31-105 (E1)
      Tool Setting 5 V/DIV., 10 ms./DIV.
      Vehicle Condition Engine idling
  4. CHECK STEERING LOCK ECU 
    Fig 9: Steering Lock E39 ECU Connector Terminals Identification
    GTY200858Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E39 ECU connector.
    2. Measure the voltage and resistance of the wire harness side connector.
      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      E39-1 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω
      E39-2 (SGND) - Body ground W-B - Body ground Ground Always Below 1 Ω
      E39-6 (IG2) - Body ground B - Body ground Ignition power supply Engine switch on (IG) 11 to 14 V
      E39-6 (IG2) - Body ground B - Body ground Ignition power supply Engine switch off Below 1 V
      E39-7 (B) - Body ground L - 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 E39 ECU connector.
    4. Measure the voltage of the connector.
      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      E39-4 (SLP1) - E39-1 (GND) BR - W-B Steering lock actuator position signal Steering is locked 11 to 14 V
      E39-4 (SLP1) - E39-1 (GND) BR - 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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