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

for Preparation Click here


DESCRIPTION

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

WIRING DIAGRAM


E184698E24


INSPECTION PROCEDURE

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

  1. Use the Data List to check if the pre-crash brake cancel switch assembly 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 assembly on
    OFF: Pre-crash brake cancel switch assembly off
    		-

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



NG
Go to step 2
OK

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

2.INSPECT PRE-CRASH BRAKE CANCEL SWITCH ASSEMBLY


    E186380E01

  1. Remove the pre-crash brake cancel switch assembly (Click here).

  1. 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

    Text in Illustration 
    *a
    		Component without harness connected
    (Pre-crash Brake Cancel Switch Assembly)

  1. Reinstall the pre-crash brake cancel switch assembly (Click here).



NG
REPLACE PRE-CRASH BRAKE CANCEL SWITCH ASSEMBLY (Click here)
OK


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

  1. Disconnect the pre-crash brake cancel switch assembly connector.

  1. Disconnect the driving support ECU connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    H33-1 - H5-5 (PBSW)
    		Always
    		Below 1 Ω
    H33-1 - Body ground
    		Always
    		10 kΩ or higher
    H33-2 - Body ground
    		Always
    		Below 1 Ω

  1. Reconnect the driving support ECU connector.

  1. Reconnect the pre-crash brake cancel switch assembly connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (PRE-CRASH BRAKE CANCEL SWITCH ASSEMBLY - DRIVING SUPPORT ECU)
OK


4.CHECK HARNESS AND CONNECTOR (PRE-CRASH BRAKE CANCEL SWITCH ASSEMBLY - BODY GROUND)

  1. Disconnect the pre-crash brake cancel switch assembly connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    H33-2 - Body ground
    		Always
    		Below 1 Ω

  1. Reconnect the pre-crash brake cancel switch assembly connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (PRE-CRASH BRAKE CANCEL SWITCH ASSEMBLY - BODY GROUND)
OK

REPLACE DRIVING SUPPORT ECU (Click here)