PRE-CRASH SAFETY SYSTEM Pre-crash Safety Brake Cancel Switch Circuit

DESCRIPTION

The driving support ECU receives pre-crash brake on/off signals from the pre-crash brake cancel switch.

WIRING DIAGRAM

A004TYAE17
*a Pre-crash Brake Cancel Switch
*b Driving Support ECU

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER (PRE-CRASH BRAKE CANCEL SWITCH)


    1. Use the Data List to check if the pre-crash brake cancel switch is functioning properly.

      Pre-Crash 2
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Pre-Crash Brake OFF Switch Pre-crash brake cancel switch signal / ON or OFF

      ON: Pre-crash brake cancel switch on

      OFF: Pre-crash brake cancel switch off

      		 -
      OK
      On screen, each item changes between ON and OFF according to above chart.

    OK

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    NG

  2. INSPECT PRE-CRASH BRAKE CANCEL SWITCH


    1. A004TWW

      Remove the pre-crash brake cancel switch Click here.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      1 - 2 Pressed Below 1 Ω
      Not pressed 10 kΩ or higher

    NG

    REPLACE PRE-CRASH BRAKE CANCEL SWITCH Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (PRE-CRASH BRAKE CANCEL SWITCH - DRIVING SUPPORT ECU AND BODY GROUND)


    1. A004QSBE01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Pre-crash Brake Cancel Switch)
      *2

      Front view of wire harness connector

      (to Driving Support ECU)

      Disconnect the D73 switch connector.

    2. Disconnect the D14 ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D73-1 - D14-5 (PBSW) Always Below 1 Ω
      D73-2 - Body ground
      D73-1 - Body ground Always 10 kΩ or higher
      Result
      Result Proceed to
      OK (for LHD) A
      OK (for RHD) B
      NG C

    A

    REPLACE DRIVING SUPPORT ECU Click here

    B

    REPLACE DRIVING SUPPORT ECU Click here

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR