2012 Toyota Prius Plug-inFACTORY OEM SERVICE PROCEDURE

Terminals Of Ecu

  1. CHECK POWER MANAGEMENT CONTROL ECU 
    Fig 1: Management Control ECU Connector Terminal Identification
    GTY335323Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A86, L135 and L136 connectors.
    2. Measure the voltage and resistance according to the value(s) in the table below.
      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      A86-2 (IG2D) - Body ground V - Body ground IG2 relay operation signal Always 131 to 230 Ω
      A86-23 (STP) - Body ground L - Body ground Stop light switch signal Brake pedal depressed 11 to 14 V
      A86-23 (STP) - Body ground L - Body ground Stop light switch signal Brake pedal released Below 1 V
      L135-1 (AM22) - Body ground W - Body ground +B power supply Always 9.5 to 16 V
      L136-7 (AM21) - Body ground W - Body ground +B power supply Always 9.5 to 16 V
      L135-6 (E1) - Body ground BR - Body ground Ground Always Below 1 Ω
      L136-4 (E12) - Body ground BR - Body ground Ground Always Below 1 Ω
      L136-24 (CA1L) - Body ground W - Body ground CAN communication line Always 10 kΩ or higher
      L136-25 (CA1H) - Body ground B - Body ground CAN communication line Always 10 kΩ or higher
      L136-17 (SSW2) - Body ground Y - Body ground Power switch signal Power switch pushed Below 1 Ω
      L136-17 (SSW2) - Body ground Y - Body ground Power switch signal Power switch not pushed 10 kΩ or higher
      L135-7 (SSW1) - Body ground B - Body ground Power switch signal Power switch pushed Below 1 Ω
      L135-7 (SSW1) - Body ground B - Body ground Power switch signal Power switch not pushed 10 kΩ or higher
      L136-1 (ACCD) - Body ground G - Body ground ACC relay operation signal Always 50.625 to 61.875 Ω
      L136-2 (IG1D) - Body ground B - Body ground IG1 relay operation signal Always 50.625 to 61.875 Ω
      L136-11 (LIN2) - Body ground L - Body ground LIN communication line Always 10 kΩ or higher

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

    3. Reconnect the A86, L135 and L136 connectors.
    4. Measure the voltage and check for pulses according to the value(s) in the table below.
      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      A86-2 (IG2D) - L135-6 (E1) V - BR IG2 signal Power switch on (IG) Output voltage at terminal AM21 or AM22 is -2 V or more
      A86-2 (IG2D) - L135-6 (E1) V - BR IG2 signal Power switch on (ACC) Below 1 V
      L135-9 (INDW) - L135-6 (E1) G - BR Warning signal Brake pedal depressed, park (P) selected, power switch on (ACC, IG) 8 to 14 V
      A86-22 (PCON) - L135-6 (E1) LG - BR P position signal Park (P) selected Pulse generation
      (See waveform 1)
      A86-28 (PPOS) - L135-6 (E1) W - BR P position signal Park (P) selected Pulse generation
      (See waveform 1)
      L136-17 (SSW2) - L135-6 (E1) Y - BR Power switch signal Power switch not pushed Output voltage at terminal AM21 or AM22 is -2 V or more
      L136-17 (SSW2) - L135-6 (E1) Y - BR Power switch signal Power switch pushed Below 1 V
      L135-7 (SSW1) - L135-6 (E1) B - BR Power switch signal Power switch not pushed Output voltage at terminal AM21 or AM22 is -2 V or more
      L135-7 (SSW1) - L135-6 (E1) B - BR Power switch signal Power switch pushed Below 1 V
      L136-1 (ACCD) - L135-6 (E1) G - BR ACC signal Power switch on (ACC) Output voltage at terminal AM21 or AM22 is -2 V or more
      L136-1 (ACCD) - L135-6 (E1) G - BR ACC signal Power switch off Below 1 V
      L136-2 (IG1D) - L135-6 (E1) B - BR IG1 signal Power switch on (IG) Output voltage at terminal AM21 or AM22 is -2 V or more
      L136-2 (IG1D) - L135-6 (E1) B - BR IG1 signal Power switch on (ACC) Below 1 V
      L135-8 (INDS) - L135-6 (E1) R - BR Vehicle condition signal Brake pedal depressed, park (P) selected 8 to 14 V
      L135-14 (SPDI) - L135-6 (E1) V - BR Vehicle speed signal Power switch on (IG), wheel rotated slowly Pulse generation
      (See waveform 2)
      L136-20 (IMO) - L135-6 (E1) L - BR Immobiliser communication status Immobiliser communicating Pulse generation
      (See waveform 3)
      L136-21 (IMI) - L135-6 (E1) R - BR Immobiliser communication status Immobiliser communicating Pulse generation
      (See waveform 4)

      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 2: Identifying Waveform 1
        GTY308625Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        Tester Connection CH1: A86-22 (PCON) - L135-6 (E1)
        CH2: A86-28 (PPOS) - L135-6 (E1)
        Tool Setting 10 V/DIV., 10 ms./DIV.
        Vehicle Condition Power switch on (IG)
      2. Waveform 2
        Fig 3: Identifying Waveform 2
        GTY108735Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        Tester Connection L135-14 (SPDI) - L135-6 (E1)
        Tool Setting 5 V/DIV., 10 ms./DIV.
        Vehicle Condition Driving at approx. 20 km/h (12 mph)

        HINT: 

        The wavelength becomes shorter as the vehicle speed increases.

      3. Waveform 3
        Fig 4: Identifying Waveform 3
        GTY323602Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        Tester Connection L136-20 (IMO) - L135-6 (E1)
        Tool Setting 5 V/DIV., 500 ms./DIV.
        Vehicle Condition Within 3 seconds after power switch on (READY), or within 3 seconds after power switch first turned on (IG) after battery disconnected and connected
      4. Waveform 4
        Fig 5: Identifying Waveform 4
        GTY180510Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        Tester Connection L136-21 (IMI) - L135-6 (E1)
        Tool Setting 5 V/DIV., 50 ms./DIV.
        Vehicle Condition Power switch on (IG)
  2. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 
    Fig 6: Certification ECU (Smart Key ECU Assembly) Connector Terminal Identification
    GTY327811Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the L62 connector.
    2. Measure the voltage and resistance according to the value(s) in the table below.
      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      L62-1 (+B) - Body ground B - Body ground +B power supply Always 11 to 14 V
      L62-9 (CANH) - Body ground BE - Body ground CAN communication line Always 10 kΩ or higher
      L62-10 (CANL) - Body ground P - Body ground CAN communication line Always 10 kΩ or higher
      L62-15 (E) - Body ground W-B - Body ground Ground Always Below 1 Ω
      L62-16 (IG) - Body ground BE - Body ground IG power supply Power switch on (IG) 11 to 14 V
      L62-29 (LIN) - Body ground L - Body ground LIN communication line Always 10 kΩ or higher

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

    3. Reconnect the L62 connector.
    4. Check for pulses according to the value(s) in the table below.
      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      L62-34 (EFII) - L62-15 (E)*1 L - W-B Immobiliser communication status Immobiliser communicating Pulse generation
      (See waveform 1)
      L62-35 (EFIO) - L62-15 (E)*1 R - W-B Immobiliser communication status Immobiliser communicating Pulse generation
      (See waveform 1)
      • *1: for Canada

      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 7: Identifying Waveform 1
        GTY335665Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        Tester Connection CH1: L62-34 (EFII) - L62-15 (E)
        CH2: L62-35 (EFIO) - L62-15 (E)
        Tool Setting 5 V/DIV., 200 ms./DIV.
        Vehicle Condition Power switch off → Power switch on (IG) → Power switch on (READY)
  3. CHECK TRANSMISSION CONTROL ECU ASSEMBLY 
    Fig 8: Transmission Control ECU Assembly Connector Terminal Identification
    GTY323619Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A23 and A24 connectors.
    2. Measure the voltage and resistance according to the value(s) in the table below.
      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      A24-1 (E1) - Body ground BR - Body ground Ground Always Below 1 Ω
      A24-5 (E02) - Body ground W-B - Body ground Ground Always Below 1 Ω
      A24-6 (E01) - Body ground W-B - Body ground Ground Always Below 1 Ω
      A23-16 (+B) - Body ground L - Body ground Ignition power supply Power switch on (IG) 11 to 14 V
      A23-16 (+B) - Body ground L - Body ground Ignition power supply Power switch off Below 1 V
      A23-15 (BATT) - Body ground SB - Body ground +B power supply Except power switch on (READY) 11 to 14 V
      A23-15 (BATT) - Body ground SB - Body ground +B power supply Power switch on (READY) 11 to 15.5 V
      A24-15 (CA1L) - Body ground P - Body ground CAN communication line Always 10 kΩ or higher
      A24-16 (CA1H) - Body ground BE - Body ground CAN communication line Always 10 kΩ or higher
      A24-24 (LIN) - Body ground L - Body ground LIN communication line Always 10 kΩ or higher
      • If the result is not as specified, there may be a malfunction in the wire harness.
  4. CHECK ID CODE BOX (IMMOBILISER CODE ECU) [for Canada] 
    Fig 9: L10 Connector Terminal Identification
    GTY325172Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the L10 connector.
    2. Measure the resistance and voltage according to the value(s) in the table below.
      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      L10-1 (+B) - L10-8 (GND) B - W-B +B power supply Always 11 to 14 V
      L10-8 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω
      L10-3 (LIN1) - Body ground L - Body ground LIN communication line Always 10 kΩ or higher

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

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Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
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  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
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