LEXUS PARKING ASSIST-SENSOR SYSTEM(w/ Intelligent Clearance Sonar System) TERMINALS OF ECU


  1. CLEARANCE WARNING ECU ASSEMBLY

    B002JHNE35

    1. Disconnect the I20 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
      I20-1 (IG) - I20-30 (E) BE - W-B IG power source signal Power switch off Below 1 V
      Power switch on (IG) 11 to 14 V
      I20-30 (E) - Body ground W-B - Body ground Ground Always Below 1 Ω

    3. Reconnect the I20 clearance warning ECU assembly connector.

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

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      I20-4 (BOF) - I20-30 (E) R - W-B Power source for front sensor circuit Power switch off Below 1 V

      • Power switch on (IG)

      • LEXUS parking assist-sensor system on

      		 11 to 14 V
      I20-6 (E5) - I20-30 (E) LG - W-B Ground for front clearance sonar Always Below 1 Ω
      I20-8 (SOF) - I20-30 (E) V - W-B Front sensor communication signal (Front clearance sonar sensor)

      • Power switch on (IG)

      • LEXUS parking assist-sensor system on

      • Shift lever in any position other than P or R

      • Vehicle speed is less than approximately 10 km/h (6 mph)

      Pulse generation

      (Refer to waveform 1)
      I20-14 (CBZ) - I20-13 (EF) LG - L Clearance warning buzzer signal Buzzer sounding

      Pulse generation

      (Refer to waveform 2)
      I20-22 (BOR) - I20-30 (E) SB - W-B Power source for rear sensor circuit Power switch off Below 1 V

      • Power switch on (IG)

      • LEXUS parking assist-sensor system on

      		 11 to 14 V
      I20-23 (E1) - I20-30 (E) L - W-B Ground for rear clearance sonar Always Below 1 Ω
      I20-24 (SOR) - I20-30 (E) R - W-B Rear sensor communication signal (Rear clearance sonar sensor)

      • Power switch on (IG)

      • LEXUS parking assist-sensor system on

      • Shift lever in R

      • Vehicle speed is less than approximately 10 km/h (6 mph)

      Pulse generation

      (Refer to waveform 1)

    5. Using an oscilloscope, check waveform 1.


      1. B002K8QN04

        Waveform 1 (Reference)

        Item Content
        Measurement terminal

        • CH1: I20-8 (SOF) - I20-30 (E)

        • CH2: I20-24 (SOR) - I20-30 (E)
        Measurement setting 5 V/DIV., 1 ms./DIV.
        Condition

        • Power switch on (IG)

        • LEXUS parking assist-sensor system on

        • Shift lever in any position other than P or R (CH1)

        • Shift lever in R (CH2)

        • Vehicle speed is less than approximately 10 km/h (6 mph)

        Tech Tips

        The waveforms for CH1 and CH2 are same.

    6. Using an oscilloscope, check waveform 2.


      1. B002KGUN05

        Waveform 2 (Reference)

        Item Content
        Measurement terminal I20-14 (CBZ) - I20-13 (EF)
        Measurement setting 2 V/DIV., 500 μs./DIV.
        Condition Buzzer sounding

        Tech Tips

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