LEXUS PARKING ASSIST-SENSOR SYSTEM No. 2 Clearance Warning Buzzer Circuit

DESCRIPTION

The clearance warning buzzer sounds to alert the driver and buzzer frequency changes depending on the distance to an obstacle.

WIRING DIAGRAM

A000ZMBE08
*a Rear Clearance Warning Buzzer
*b Clearance Warning ECU

PROCEDURE


  1. PERFORM ACTIVE TEST USING INTELLIGENT TESTER


    1. Select the ACTIVE TEST, use the intelligent tester to generate a control command, and then check that the buzzer operates.

      Clearance Sonar
      Tester Display Test Part Control Range Diagnostic Note
      Rear Buzzer Rear clearance warning buzzer Operate or Stop -
      OK
      Rear clearance warning buzzer sounds.

    OK

    PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    NG

  2. CHECK HARNESS AND CONNECTOR (CLEARANCE WARNING ECU - REAR CLEARANCE WARNING BUZZER)


    1. Disconnect the L159 ECU connector.

      A000ZZGE04
      *1 Rear view of wire harness connector: (to Clearance Warning ECU)
      *2 Front view of wire harness connector: (to Rear Clearance Warning Buzzer)

    2. Disconnect the R21 buzzer connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance
      Tester Connection Condition Specified Condition
      L159-10 (BBZ) - R21-1 (Z+) Always Below 1 Ω
      L159-11 (EF) - R21-2 (Z-) Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. REPLACE REAR CLEARANCE WARNING BUZZER


    1. Temporarily replace the rear clearance warning buzzer with a new or normally functioning one Click here.

    2. Check the clearance warning buzzer sounds.

      OK
      Rear clearance warning buzzer sounds.

    OK

    END (REAR CLEARANCE WARNING BUZZER IS DEFECTIVE)

    NG

    REPLACE CLEARANCE WARNING ECU Click here