LEXUS PARKING ASSIST-SENSOR SYSTEM TERMINALS OF ECU


  1. CLEARANCE WARNING ECU ASSEMBLY

    A01MTJ3N11

    1. Disconnect the K44 clearance warning ECU assembly connector.

    2. Measure the voltage and resistance on the wire harness side connector according to the value(s) in the table below.

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      K44-12 (IG) - K44-27 (E) R - BR IG power source signal Power switch off Below 1 V
      Power switch on (IG) 11 to 14 V
      K44-27 (E) - Body ground BR - Body ground Ground Always Below 1 Ω
      K44-38 (CLSW) - K44-27 (E) SB - BR Back sonar or clearance sonar switch assembly power source signal

      • Power switch on (IG)

      • Back sonar or clearance sonar switch assembly off

      		 Below 1 V

      • Power switch on (IG)

      • Back sonar or clearance sonar switch assembly on

      		 11 to 14 V

    3. Reconnect the K44 clearance warning ECU assembly connector.

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

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      K44-1 (S1) - K44-2 (E1) B - W Sensor communication signal (Rear right sensor)

      • Power switch on (IG)

      • Back sonar or clearance sonar switch assembly on

      • Shift lever in R

      Pulse generation

      (See waveform 1)
      K44-2 (E1) - K44-27 (E) W - BR Ground for sensor (Rear right sensor) Always Below 1 V
      K44-3 (S2) - K44-4 (E2) BE - R Sensor communication signal (Rear left sensor)

      • Power switch on (IG)

      • Back sonar or clearance sonar switch assembly on

      • Shift lever in R

      Pulse generation

      (See waveform 1)
      K44-4 (E2) - K44-27 (E) R - BR Ground for sensor (Rear left sensor) Always Below 1 V
      K44-6 (S3) - K44-7 (E3) SB - LG Sensor communication signal (Rear right center sensor)

      • Power switch on (IG)

      • Back sonar or clearance sonar switch assembly on

      • Shift lever in R

      Pulse generation

      (See waveform 1)
      K44-7 (E3) - K44-27 (E) LG - BR Ground for sensor (Rear right center sensor) Always Below 1 V
      K44-8 (S4) - K44-9 (E4) G - L Sensor communication signal (Rear left center sensor)

      • Power switch on (IG)

      • Back sonar or clearance sonar switch assembly on

      • Shift lever in R

      Pulse generation

      (See waveform 1)
      K44-9 (E4) - K44-27 (E) L - BR Ground for sensor (Rear left center sensor) Always Below 1 V
      K44-11 (CBZ) - K44-10 (EF) BE - V Clearance warning buzzer signal Buzzer sounding

      Pulse generation

      (See waveform 2)
      K44-19 (S5) - K44-20 (E5) R - LG Sensor communication signal (Front right sensor)

      • Power switch on (IG)

      • Back sonar or clearance sonar switch assembly on

      • Shift lever in R

      Pulse generation

      (See waveform 1)

      • Power switch on (IG)

      • Back sonar or clearance sonar switch assembly on

      • Shift lever in any position other than P or R

      • Less than approximately 15 km/h (9 mph) if vehicle speed increasing

      • Less than approximately 10 km/h (6 mph) if vehicle speed decreasing
      K44-20 (E5) - K44-27 (E) LG - BR Ground for sensor (Front right sensor) Always Below 1 V
      K44-21 (S6) - K44-22 (E6) V - B Sensor communication signal (Front left sensor)

      • Power switch on (IG)

      • Back sonar or clearance sonar switch assembly on

      • Shift lever in R

      Pulse generation

      (See waveform 1)

      • Power switch on (IG)

      • Back sonar or clearance sonar switch assembly on

      • Shift lever in any position other than P or R

      • Less than approximately 15 km/h (9 mph) if vehicle speed increasing

      • Less than approximately 10 km/h (6 mph) if vehicle speed decreasing
      K44-22 (E6) - K44-27 (E) B - BR Ground for sensor (Front left sensor) Always Below 1 V
      K44-23 (S7) - K44-24 (E7) W - G Sensor communication signal (Front right center sensor)

      • Power switch on (IG)

      • Back sonar or clearance sonar switch assembly on

      • Shift lever in any position other than P or R

      • Less than approximately 15 km/h (9 mph) if vehicle speed increasing

      • Less than approximately 10 km/h (6 mph) if vehicle speed decreasing

      Pulse generation

      (See waveform 1)
      K44-24 (E7) - K44-27 (E) G - BR Ground for sensor (Front right center sensor) Always Below 1 V
      K44-25 (S8) - K44-26 (E8) GR - P Sensor communication signal (Front left center sensor)

      • Power switch on (IG)

      • Back sonar or clearance sonar switch assembly on

      • Shift lever in any position other than P or R

      • Less than approximately 15 km/h (9 mph) if vehicle speed increasing

      • Less than approximately 10 km/h (6 mph) if vehicle speed decreasing

      Pulse generation

      (See waveform 1)
      K44-26 (E8) - K44-27 (E) P - BR Ground for sensor (Front left center sensor) Always Below 1 V

    5. Using an oscilloscope, check waveform 2.


      1. A011P2WE01

        Waveform 2 (Reference)

        Item Content
        Terminal No. (Symbol)

        K44-1 (S1) - K44-2 (E1)

        K44-3 (S2) - K44-4 (E2)

        K44-6 (S3) - K44-7 (E3)

        K44-8 (S4) - K44-9 (E4)
        Tool Setting 2 V/DIV., 100 μsec./DIV.
        Condition

        • Power switch on (IG)

        • Back sonar or clearance sonar switch assembly on

        • Shift lever in R
        Item Content
        Terminal No. (Symbol)

        K44-19 (S5) - K44-20 (E5)

        K44-21 (S6) - K44-22 (E6)
        Tool Setting 2 V/DIV., 100 μsec./DIV.
        Condition

        • Power switch on (IG)

        • Back sonar or clearance sonar switch assembly on

        • Shift lever in R

        • Power switch on (IG)

        • Back sonar or clearance sonar switch assembly on

        • Shift lever in any position other than P or R

        • Less than approximately 15 km/h (9 mph) if vehicle speed increasing

        • Less than approximately 10 km/h (6 mph) if vehicle speed decreasing
        Item Content
        Terminal No. (Symbol)

        K44-23 (S7) - K44-24 (E7)

        K44-25 (S8) - K44-26 (E8)
        Tool Setting 2 V/DIV., 100 μsec./DIV.
        Condition

        • Power switch on (IG)

        • Back sonar or clearance sonar switch assembly on

        • Shift lever in any position other than P or R

        • Less than approximately 15 km/h (9 mph) if vehicle speed increasing

        • Less than approximately 10 km/h (6 mph) if vehicle speed decreasing

    6. Using an oscilloscope, check waveform 1.


      1. A011MMAN03

        Waveform 1 (Reference)

        Item Content
        Terminal No. (Symbol) K44-11 (CBZ) - K44-10 (EF)
        Tool Setting 2 V/DIV., 100 μsec./DIV.
        Condition Buzzer sounding

        Tech Tips

        The amplitude of the waveform changes according to the set volume.