LEXUS PARKING ASSIST-SENSOR SYSTEM TERMINALS OF ECU


  1. CLEARANCE WARNING ECU ASSEMBLY

    B002JVBN04

    1. Disconnect the 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
      I20-12 (IG) - I20-27 (E) BE - W-B IG power source signal Power switch off Below 1 V
      Power switch on (IG) 11 to 14 V
      I20-27 (E) - Body ground W-B - Body ground Ground Always Below 1 Ω
      I20-38 (CLSW) - I20-27 (E) LG - W-B Combination switch assembly (clearance sonar main switch) power source signal

      • Power switch on (IG)

      • Combination switch assembly (clearance sonar main switch) off

      		 Below 1 V

      • Power switch on (IG)

      • Combination switch assembly (clearance sonar main switch) on

      		 11 to 14 V

    3. Reconnect the 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
      I20-1 (S1) - I20-2 (E1) B - L Sensor communication signal (Rear corner sensor RH)

      • Power switch on (IG)

      • Combination switch assembly (clearance sonar main switch) on

      • Shift lever in R

      Pulse generation

      (See waveform 1)
      I20-2 (E1) - I20-27 (E) L - W-B Ground for sensor (Rear corner sensor RH) Always Below 1 V
      I20-3 (S2) - I20-4 (E2) R - L Sensor communication signal (Rear corner sensor LH)

      • Power switch on (IG)

      • Combination switch assembly (clearance sonar main switch) on

      • Shift lever in R

      Pulse generation

      (See waveform 1)
      I20-4 (E2) - I20-27 (E) L - W-B Ground for sensor (Rear corner sensor LH) Always Below 1 V
      I20-6 (S3) - I20-7 (E3) B - W Sensor communication signal (Rear center sensor RH)

      • Power switch on (IG)

      • Combination switch assembly (clearance sonar main switch) on

      • Shift lever in R

      Pulse generation

      (See waveform 1)
      I20-7 (E3) - I20-27 (E) W - W-B Ground for sensor (Rear center sensor RH) Always Below 1 V
      I20-8 (S4) - I20-9 (E4) LG - L Sensor communication signal (Rear center sensor LH)

      • Power switch on (IG)

      • Combination switch assembly (clearance sonar main switch) on

      • Shift lever in R

      Pulse generation

      (See waveform 1)
      I20-9 (E4) - I20-27 (E) L - W-B Ground for sensor (Rear center sensor LH) Always Below 1 V
      I20-11 (CBZ) - I20-10 (EF) LG - L Clearance warning buzzer signal Buzzer sounding

      Pulse generation

      (See waveform 2)
      I20-19 (S5) - I20-20 (E5) V - LG Sensor communication signal (Front corner sensor RH)

      • Power switch on (IG)

      • Combination switch assembly (clearance sonar main switch) on

      • Shift lever in R

      Pulse generation

      (See waveform 1)

      • Power switch on (IG)

      • Combination switch assembly (clearance sonar main switch) 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
      I20-20 (E5) - I20-27 (E) LG - W-B Ground for sensor (Front corner sensor RH) Always Below 1 V
      I20-21 (S6) - I20-22 (E6) W - P Sensor communication signal (Front corner sensor LH)

      • Power switch on (IG)

      • Combination switch assembly (clearance sonar main switch) on

      • Shift lever in R

      Pulse generation

      (See waveform 1)

      • Power switch on (IG)

      • Combination switch assembly (clearance sonar main switch) 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
      I20-22 (E6) - I20-27 (E) P - W-B Ground for sensor (Front corner sensor LH) Always Below 1 V
      I20-23 (S7) - I20-24 (E7) V - L Sensor communication signal (Front center sensor RH)

      • Power switch on (IG)

      • Combination switch assembly (clearance sonar main switch) 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)
      I20-24 (E7) - I20-27 (E) L - W-B Ground for sensor (Front center sensor RH) Always Below 1 V
      I20-25 (S8) - I20-26 (E8) R - G Sensor communication signal (Front center sensor LH)

      • Power switch on (IG)

      • Combination switch assembly (clearance sonar main switch) 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)
      I20-26 (E8) - I20-27 (E) G - W-B Ground for sensor (Front center sensor LH) Always Below 1 V

    5. Using an oscilloscope, check waveform 1.


      1. B002JHYE01

        Waveform 1 (Reference)

        Item Content
        Terminal No. (Symbol)

        I20-1 (S1) - I20-2 (E1)

        I20-3 (S2) - I20-4 (E2)

        I20-6 (S3) - I20-7 (E3)

        I20-8 (S4) - I20-9 (E4)
        Tool Setting 2 V/DIV., 100 μsec./DIV.
        Condition

        • Power switch on (IG)

        • Combination switch assembly (clearance sonar main switch) on

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

        I20-19 (S5) - I20-20 (E5)

        I20-21 (S6) - I20-22 (E6)
        Tool Setting 2 V/DIV., 100 μsec./DIV.
        Condition

        • Power switch on (IG)

        • Combination switch assembly (clearance sonar main switch) on

        • Shift lever in R

        • Power switch on (IG)

        • Combination switch assembly (clearance sonar main switch) 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)

        I20-23 (S7) - I20-24 (E7)

        I20-25 (S8) - I20-26 (E8)
        Tool Setting 2 V/DIV., 100 μsec./DIV.
        Condition

        • Power switch on (IG)

        • Combination switch assembly (clearance sonar main switch) 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 2.


      1. B002HPHN03

        Waveform 2 (Reference)

        Item Content
        Terminal No. (Symbol) I20-11 (CBZ) - I20-10 (EF)
        Tool Setting 2 V/DIV., 500 μsec./DIV.
        Condition Buzzer sounding

        Tech Tips

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