THEFT DETERRENT SYSTEM > Engine Hood Courtesy Switch Circuit

for Preparation Click here


DESCRIPTION

The security courtesy switch is installed together with the hood lock. This switch turns off when the engine hood is closed and turns on when the engine hood is opened.
If the security courtesy switch signal wire is cut or disconnected during the armed state, the main body ECU (multiplex network body ECU) detects this and sounds the alarm.

WIRING DIAGRAM


B235172E03


INSPECTION PROCEDURE

1.READ VALUE USING INTELLIGENT TESTER

  1. Connect the intelligent tester to the DLC3.

  1. Turn the power switch on (IG).

  1. Turn the intelligent tester on.

  1. Enter the following menus: Body / Main Body / Data List.

  1. According to the display on the intelligent tester, read the Data List.

    Main Body (Main Body ECU (Multiplex Network Body ECU)) 
    Tester Display
    		Measurement Item/Range
    		Normal Condition
    		Diagnostic Note
    Hood Courtesy SW
    		Security courtesy switch signal/ON or OFF
    		ON: Engine hood open
    OFF: Engine hood closed
    		-

    OK:
    The indicator on the intelligent tester switches between ON and OFF in accordance with the security courtesy switch (hood lock assembly) status.



NG
Go to step 2
OK

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) (Click here)  

2.INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY


  1. Disconnect the 2C instrument panel junction block assembly and MB main body ECU (multiplex network body ECU) connectors.


    B220554E13

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    2C-38 - MB-20 (HCTY)
    		Always
    		Below 1 Ω
    2C-38 - Body ground
    		Always
    		10 kΩ or higher


    Text in Illustration 
    *a
    		Component without harness connected
    (Instrument Panel Junction Block Assembly)
    		-
    		-



NG
REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (Click here)
OK


3.CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - SECURITY COURTESY SWITCH - BODY GROUND)

  1. Disconnect the A45 security courtesy switch (hood lock assembly) connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    A45-1 (+) - 2C-38
    		Always
    		Below 1 Ω
    A45-1 (+) - Body ground
    		Always
    		10 kΩ or higher
    A45-4 (E) - Body ground
    		Always
    		Below 1 Ω



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


4.CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - SECURITY COURTESY SWITCH - BODY GROUND)

  1. Disconnect the H16 main body ECU (multiplex network body ECU) connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    A45-2 (HWM+) - H16-12 (SLF+)
    		Always
    		Below 1 Ω
    A45-2 (HWM+) - Body ground
    		Always
    		10 kΩ or higher
    A45-3 (HWM-) - Body ground
    		Always
    		Below 1 Ω



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


5.INSPECT SECURITY COURTESY SWITCH (HOOD LOCK ASSEMBLY)


  1. Remove the hood lock assembly (Click here).


    B273442E01

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    1 (+) - 4 (E)
    		Locked
    		10 kΩ or higher
    1 (+) - 4 (E)
    		Unlocked
    		Below 1 Ω
    2 (HWM+) - 3 (HWM-)
    		Always
    		Below 1 Ω


    Text in Illustration 
    *A
    		for LHD
    		*B
    		for RHD
    *1
    		Unlocked
    		*2
    		Locked
    *a
    		Component without harness connected
    (Security Courtesy Switch (Hood Lock Assembly))
    		-
    		-



NG
REPLACE SECURITY COURTESY SWITCH (HOOD LOCK ASSEMBLY) (Click here)
OK

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) (Click here)