LEXUS PARKING ASSIST-SENSOR SYSTEM TERMINALS OF ECU


  1. CHECK CLEARANCE WARNING ECU

    A01GYMAE09

    1. Disconnect the L159 ECU connector.

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

      Terminal No. (Symbols) Wiring Color Terminal Description Condition Specified Condition
      L159-15 (IG) - L159-17 (E) V - W-B IG signal / IG power source signal Power switch off Below 1 V
      Power switch on (IG) 11 to 14 V
      L159-17 (E) - Body ground W-B - Body ground ECU ground Always Below 1 Ω

    3. Reconnect the L159 ECU connector.

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

      Terminal No. (Symbols) Wiring Color Terminal Description Condition Specified Condition
      L159-1 (CBZ) - L159-17 (E) W - W-B Front clearance warning buzzer signal Buzzer not sounding Below 1 V
      Buzzer sounding Waveform 2
      L159-2 (EE) - L159-17 (E) B - W-B Front clearance warning buzzer signal Buzzer not sounding Below 1 V
      Buzzer sounding Waveform 2
      L159-7 (BOR) - L159-18 (E2) B - R Rear sensor circuit power source Power switch off Below 1 V
      Power switch on (IG), clearance sonar main switch ON 7.2 to 8.8 V
      L159-9 (SOF) - L159-19 (E1) G - R Front sensor circuit power source Power switch on (IG), clearance sonar main switch ON Waveform 1
      L159-10 (BBZ) - L159-17 (E) W - W-B Rear clearance warning buzzer signal Power switch off Below 1 V
      Power switch on (IG) 11 to 14 V
      L159-11 (EF) - L159-17 (E) B - W-B Rear clearance warning buzzer signal Buzzer sounding Waveform 2
      L159-18 (E2) - L159-17 (E) R - W-B Rear sensor circuit ground Always Below 1 Ω
      L159-19 (E1) - L159-17 (E) R - W-B Front sensor circuit ground Always Below 1 Ω
      L159-21 (BOF) - L159-19 (E1) B - R Front sensor circuit power source Power switch off Below 1 V
      Power switch on (IG), clearance sonar main switch ON 7.2 to 8.8 V
      L159-24 (SOR) - L159-18 (E2) G - R Rear sensor circuit power source Power switch on (IG), clearance sonar main switch ON Waveform 1
    5. A01GWAKE01

      Using an oscilloscope, check waveform 1.

      Waveform 1 (Reference)
      Item Content
      Terminal No. (Symbols)

      • CH: 1 L159-9 (SOF) - L159-19 (E1)

      • CH: 2 L159-24 (SOR) - L159-18 (E2)
      Tool Setting 2 V/DIV., 1 msec./DIV.
      Condition Power switch on (IG), clearance sonar main switch ON.
    6. A01H1QS

      Using an oscilloscope, check waveform 2.

      Waveform 2 (Reference)
      Item Content
      Terminal No. (Symbols)

      • L159-1 (CBZ) - L159-17 (E)

      • L159-2 (EE) - L159-17 (E)

      • L159-11 (EF) - L159-17 (E)
      Tool Setting 5 V/DIV., 1 msec./DIV.
      Condition Power switch on (IG), clearance sonar main switch ON, shift lever in R position and sensor is in detecting state

      Note


      • The waveforms of CBZ and EE are offset by a half cycle. EF is not synchronized with CBZ and EE.

      • The waveform's amplitude varies depending on the volume setting.