PRE-COLLISION SYSTEM TERMINALS OF ECU

  1. CHECK PRE-COLLISION CITY SENSOR

    U184792E02

    1. Disconnect the Q12 pre-collision city sensor connector.

      Note:

      • DTCs may be output when connectors are disconnected during inspection. Therefore, be sure to clear the DTCs using the GTS once the inspection has been completed.

      • Do not apply excessive force to the Q12 pre-collision city sensor connector.

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

      Terminal No. (Symbol)

      Wiring Color

      Terminal Description

      Condition

      Specified Condition

      Q12-8 (BUZ) - Q12-10 (GND)

      GR - W-B

      Pre-collision city buzzer operation signal

      Ignition switch ON, pre-collision city buzzer not operating

      11 to 14 V

      Ignition switch ON, pre-collision city buzzer operating

      0 to 1.5 V

      Q12-9 (PCSW) - Q12-10 (GND)

      B - W-B

      Pre-collision system cancel switch signal

      Pre-collision system cancel switch being pressed

      Below 1 Ω

      Pre-collision system cancel switch not being pressed

      100 kΩ or higher

      Q12-7 (IG1) - Q12-10 (GND)

      L - W-B

      Power source

      Ignition switch ON

      11 to 14 V

      Ignition switch off

      Below 1 V

      Q12-10 (GND) - Body ground

      W-B - Body ground

      Ground

      Always

      Below 1 Ω
      Tip:

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

    3. Reconnect the Q12 pre-collision city sensor connector.

    4. Check for pulses according to the value(s) in the table below.

      Terminal No. (Symbol)

      Wiring Color

      Terminal Description

      Condition

      Specified Condition

      Q12-5 (CA1P) - Q12-10 (GND)

      R - W-B

      CAN communication signal

      Ignition switch ON

      Pulse generation

      (See waveform 1)

      Q12-11 (CA1N) - Q12-10 (GND)

      W - W-B

      CAN communication signal

      Ignition switch ON

      Pulse generation

      (See waveform 1)
    5. E318038E06

      Waveform 1

      1. CAN communication signal

        Item

        Content

        Tester Connection

        • CH1: Q12-5 (CA1P) - Q12-10 (GND)

        • CH2: Q12-11 (CA1N) - Q12-10 (GND)

        Tool Setting

        1 V/DIV., 50 μsec./DIV.

        Condition

        Ignition switch ON
        Tip:

        If the result is not as specified, the CAN bus line, terminating resistor circuit (or part with this circuit) or pre-collision city sensor is malfunctioning.