SMART KEY SYSTEM (for Start Function) TERMINALS OF ECU


  1. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    A01HYSPE15

    1. Disconnect the I78 and A43 connectors.

    2. Measure the voltage and resistance according to the value(s) in the table below.

      Tech Tips

      Measure the values on the wire harness side with the connector disconnected.

      Tester Connection Input/Output Wiring Color Terminal Description Condition Specified Condition Related Data List Item
      A43-7 (STA) - Body ground Input V - Body ground When starting the engine, this monitors the voltage sent from terminal STAR to the starter relay to judge whether the engine is "being started". 20°C (68°F) 93.75 to 136.36 Ω -
      A43-5 (STAR) - Body ground Input/Output P - Body ground

      Outputs voltage to the starter relay


      • Outputs voltage (12 V) to the starter relay when starting the engine. (Max. 30 sec. Turns off when an engine speed of 500 rpm or more continues for 500 ms or more.)

      Tech Tips

      When Hi is selected, a start request signal (STAR) will not be output even though a start request signal (STSW) is input.

      		 Shift lever in any position other than P or N → shift lever in P or N (at 20°C (68°F)) 10 kΩ or higher → 93.75 to 136.36 Ω -

      Receives neutral start switch (P, N position detection) signal


      • Monitors whether the neutral start switch is on (P or N) or off (other than P or N). Applies voltage via a resistor (large) in the certification ECU (smart key ECU assembly). When the neutral start switch is on, due to the starter relay coil resistance (small) using some of the voltage, the voltage at terminal STAR will be low (2.7 V or less), and when the neutral start switch is off, the voltage will be high (9 V or more).

      Perform the following operations except while the engine is cranking:


      • Shift lever in any position other than P or N → shift lever in P or N(at 20°C (68°F))

      		 30 kΩ or higher → 93.75 to 136.36 Ω Neutral SW/ Clutch SW
      A43-16 (NE) - Body ground Input G - Body ground Engine speed signal Always 10 kΩ or higher Engine Condition
      A43-9 (IG2D) - Body ground Output R - Body ground IG2 signal 20°C (68°F) Approximately 302.97 Ω IG2 Relay Monitor(Outside)
      A43-18 (STP1) - Body ground Input V - Body ground Stop light switch signal Brake pedal released → Brake pedal depressed 9 V or higher → 1 V or less Stop Light Switch1
      A43-2 (+B) - A43-11 (E) Input W - W Power source Always 11 to 14 V -
      I78-26 (SLP) - A43-11 (E) Input P - W Steering lock position signal Always 10 kΩ or higher Steering Unlock Switch
      A43-11 (E) - Body ground - W - Body ground GND Always Below 1 Ω -
      I78-30 (SSW2) - Body ground Input V - Body ground

      SSW2 contact signal

      Tech Tips

      Backup for SSW1. Behaves the same way as SSW1.

      		 Engine switch pushed → Engine switch not pushed Below 1 Ω → 10 kΩ or higher Start Switch2
      I78-28 (SSW1) - Body ground Input R - Body ground SSW1 contact signal Engine switch pushed → Engine switch not pushed Below 1 Ω → 10 kΩ or higher Start Switch1
      I78-4 (ACCD) - Body ground Output W - Body ground ACC signal 20°C (68°F) 81.49 to 118.98 Ω ACC Relay Monitor
      I78-6 (IG1D) - Body ground Output P - Body ground IG1 signal 20°C (68°F) 40.74 to 59.49 Ω IG1 Relay Monitor(Outside)
      A43-10 (CUTB) - A43-11 (E) Input L - W Dark current cut pin* Always 11 to 14 V -
      I78-27 (SPD) - Body ground Input V - Body ground Vehicle speed signal Always 30 kΩ or higher Vehicle Speed Signal

      • *: In order to prevent the vehicle battery from being depleted when the vehicle is shipped long distances, a fuse that cuts unnecessary electrical load while the vehicle is being shipped is set in the circuit. If the fuse is removed, the circuit becomes open. If the fuse that is between the vehicle battery and terminal CUTB is removed and the circuit is open, the certification ECU (smart key ECU assembly) changes to a certain control mode (example: the transmission of electric waves every 0.25 seconds. that form the detection area stops).

    3. Reconnect the F63 and F65 connectors.

    4. Measure the voltage and check for pulses according to the value(s) in the table below.

      Tester Connection Input/Output Wiring Color Terminal Description Condition Specified Condition Related Data List Item
      A43-7 (STA) - A43-11 (E) Input V - W When starting the engine, this monitors the voltage sent from terminal STAR to the starter relay to judge whether the engine is "being started". With the brake pedal depressed, the engine switch is pressed and held (starter on) → After approx. 1 sec. has elapsed, the engine switch is released (starter off) 6 V or higher*1 → 1.5 V or less -
      A43-5 (STAR) - A43-11 (E) Input/Output P - W

      Outputs voltage to the starter relay


      • Outputs voltage (12 V) to the starter relay when starting the engine. (Max. 30 sec. Turns off when an engine speed of 500 rpm or more continues for 500 ms or more.)

      Tech Tips

      When Hi is selected, a start request signal (STAR) will not be output even though a start request signal (STSW) is input.

      		 With the brake pedal depressed, the engine switch is pressed and held → After approx. 1 sec. has elapsed, the engine switch is released 6 V or higher*1 → 1.5 V or less -

      Receives neutral start switch (P, N position detection) signal


      • Monitors whether the neutral start switch is on (P or N) or off (other than P or N). Applies voltage via a resistor (large) in the certification ECU (smart key ECU assembly). When the neutral start switch is on, due to the starter relay coil resistance (small) using some of the voltage, the voltage at terminal STAR will be low (2.7 V or less), and when the neutral start switch is off, the voltage will be high (9 V or more).

      Perform the following operations except while the engine is cranking:


      • Shift lever in any position other than P or N → shift lever in P or N

      		 9 V or higher → 2.7 V or less Neutral SW/ Clutch SW
      A43-16 (NE) - A43-11 (E) Input G - W Engine speed signal Idling (engine warmed up)

      Pulse generation

      (See waveform 1)

      		 Engine Condition
      A43-9 (IG2D) - A43-11 (E) Output R - W IG2 signal Engine switch on (ACC) → Engine switch on (IG) 1 V or less → 9 V or higher IG2 Relay Monitor(Outside)
      A43-18 (STP1) - A43-11 (E) Input V - W Stop light switch signal Brake pedal released → Brake pedal depressed 1 V or less → 9 V or higher Stop Light Switch1
      I78-26 (SLP) - A43-11 (E) Input P - W Steering lock position signal Steering wheel locked → Steering wheel unlocked*2 11 to 14 V → 1.2 V or less Steering Unlock Switch
      I78-29 (SLR+) - A43-11 (E) Output SB - W

      Steering lock motor operation command signal

      (Steering lock motor operation permission signal sent from the certification ECU (smart key ECU assembly))

      		 Steering lock motor stopped → Steering lock motor operating → Steering lock motor stopped*3

      Pulse generation

      (See waveform 2)

      		 -
      I78-25 (P) - A43-11 (E) Input R - W P position signal Shift lever in P → Shift lever not in P 9 V or higher → 1.5 V or less Shift P Signal
      I78-30 (SSW2) - A43-11 (E) Input V - W

      SSW2 contact signal

      Tech Tips

      Backup for SSW1. Behaves the same way as SSW1.

      		 Engine switch not pushed → Engine switch pushed 9 V or higher → 1 V or less Start Switch2
      I78-28 (SSW1) - A43-11 (E) Input R - W SSW1 contact signal Engine switch not pushed → Engine switch pushed 9 V or higher → 1 V or less Start Switch1
      I78-4 (ACCD) - A43-11 (E) Output W - W ACC signal Engine switch off → Engine switch on (ACC) 1 V or less → 8.5 V or higher ACC Relay Monitor
      I78-6 (IG1D) - A43-11 (E) Output P - W IG1 signal Engine switch on (ACC) → Engine switch on (IG) 1 V or less → 9 V or higher IG1 Relay Monitor(Outside)
      I78-27 (SPD) - A43-11 (E) Input V - W Vehicle speed signal Vehicle being driven at approx. 5 km/h (3 mph)

      Pulse generation

      (See waveform 3)

      		 Vehicle Speed Signal

      Tech Tips


      • *1: While the engine is cranking, the battery voltage may drop to approximately 6 V.

      • *2: When the engine switch is turned off with the shift lever in P and any of the doors are opened or closed, the steering wheel will be locked. When the engine switch is turned on (ACC) or on (IG), the steering wheel will be unlocked.

      • *3: When all of the following conditions are met, open any of the doors to operate the steering lock motor.


        • The shift lever is in P.

        • The engine switch is off.

        • While carrying the electrical key transmitter sub-assembly, the engine switch is turned on (IG) and the steering is unlocked.

    5. Using an oscilloscope, check the waveform of the ECU.


      1. A01I1EBE01

        Waveform 1

        Item Content
        Tester Connection A43-16 (NE) - A43-11 (E)
        Tool Setting 2 V/DIV., 2 ms./DIV.
        Vehicle Condition Idling (engine warmed up)

        Tech Tips

        The wavelength becomes shorter as the engine speed increases.

      2. A01HZOEE01
        Text in Illustration
        *a Steering lock motor not operating
        *b Steering lock motor operating

        Waveform 2

        Item Content
        Tester Connection I78-29 (SLR+) - A43-11 (E)
        Tool Setting 2 V/DIV., 200 ms./DIV.
        Vehicle Condition

        Steering lock motor stopped →

        Steering lock motor operating →

        Steering lock motor stopped

        Tech Tips

        *1: When all of the following conditions are met, open any of the doors to operate the steering lock motor.


        • The shift lever is in P.

        • While carrying the electrical key transmitter sub-assembly, the engine switch is turned on (IG) and the steering is unlocked.

        • The engine switch is off.

      3. A01HYUYE01

        Waveform 3

        Item Content
        Tester Connection I78-27 (SPD) - A43-11 (E)
        Tool Setting 5 V/DIV., 20 ms./DIV.
        Vehicle Condition Engine switch on (IG), vehicle being driven at approx. 5 km/h (3 mph)

        Tech Tips

        The wavelength becomes shorter as the vehicle speed increases.