THEFT DETERRENT SYSTEM > Security Horn Circuit

for Preparation Click here


DESCRIPTION

When the theft deterrent system is switched from the armed state to the alarm sounding state, the main body ECU controls the security horn.

WIRING DIAGRAM


B213807E01


INSPECTION PROCEDURE

NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure

1.PERFORM ACTIVE TEST USING INTELLIGENT TESTER

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the intelligent tester on.

  1. Enter the following menus: Body Electrical / Main Body / Active Test.

  1. According to the display on the tester, perform the Active Test.

    Main Body 
    Tester Display
    		Test Part
    		Control Range
    		Diagnostic Note
    Security Horn
    		Security Horn
    		ON/OFF
    		-

    OK:
    The security horn sounds and stops correctly when operating it through the intelligent tester.



NG
Go to step 2
OK

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

2.INSPECT SECURITY HORN ASSEMBLY


    B216880

  1. Remove the security horn assembly (Click here).

  1. Connect a positive battery lead to terminal 1 of the security horn assembly, and a negative battery lead to the horn body.

  1. Check operation of the horn.

    OK:
    Measurement Condition
    		Specified Condition
    Battery positive (+) → Terminal 1
    		Horn sounds
    Battery negative (-) → Horn body



NG
REPLACE SECURITY HORN ASSEMBLY (Click here)
OK


3.INSPECT S-HORN RELAY
E109078E04

  1. Remove the S-HORN relay.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    3 - 5
    		Voltage is not applied between terminals 1 and 2
    		10 kΩ or higher
    Apply the battery voltage between terminals 1 and 2
    		Below 1 Ω



NG
REPLACE S-HORN RELAY
OK


4.CHECK HARNESS AND CONNECTOR (S-HORN RELAY - SECURITY HORN ASSEMBLY)


    B213808E01

  1. Disconnect the A43 security horn assembly connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    3 - A43-1
    		Always
    		Below 1 Ω
    A43-1 - Body ground
    		Always
    		10 kΩ or higher

Text in Illustration 
*1
Front view of wire harness connector
(to S-HORN relay)
*2
Front view of wire harness connector
(to Security Horn)


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


5.CHECK HARNESS AND CONNECTOR (BATTERY - S-HORN RELAY)
B216881E01

  1. Measure the voltage on the junction block side according to the value(s) in the table below.

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    2 - Body ground
    		Always
    		11 to 14 V
    5 - Body ground
    		Always
    		11 to 14 V

Text in Illustration 
*1
Front view of wire harness connector
(to S-HORN relay)


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


6.CHECK HARNESS AND CONNECTOR (S-HORN RELAY - INSTRUMENT PANEL J/B)
B213809E01

  1. Disconnect the 3B instrument panel junction block connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    3B-40 - 1
    		Always
    		Below 1 Ω
    3B-40 - Body ground
    		Always
    		10 kΩ or higher

Text in Illustration 
*1
Front view of wire harness connector
(to S-HORN relay)
*2
Front view of wire harness connector
(to Instrument Panel Junction Block)


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


7.REPLACE MAIN BODY ECU

  1. Temporarily replace the main body ECU with a new or normally functioning one (Click here).


NEXT


8.PERFORM ACTIVE TEST USING INTELLIGENT TESTER

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the intelligent tester on.

  1. Enter the following menus: Body Electrical / Main Body / Active Test.

  1. According to the display on the tester, perform the Active Test.

    Main Body 
    Tester Display
    		Test Part
    		Control Range
    		Diagnostic Note
    Security Horn
    		Security Horn
    		ON/OFF
    		-

    OK:
    The security horn sounds and stops correctly when operating it through the intelligent tester.



NG
REPLACE INSTRUMENT PANEL JUNCTION BLOCK
OK

END (MAIN BODY ECU IS DEFECTIVE)