THEFT DETERRENT SYSTEM > Security Horn Circuit


DESCRIPTION

  1. When the theft deterrent system is operating, the multiplex network body ECU outputs a signal continuously at 0.4 second intervals, causing the security horn to sound.

WIRING DIAGRAM


B108133E03


INSPECTION PROCEDURE

1.PERFORM ACTIVE TEST USING INTELLIGENT TESTER (SECURITY HORN)
  1. Select the Active Test, use the intelligent tester to generate a control command, and then check that the security horn sounds.

    Multiplex network body ECU 
    Item
    Test Details
    Diagnostic Note
    Security Horn
    Security horn ON/OFF
    -

    OK:
    Security horn operates normally.



NG
Go to step 2
OK

REPLACE COWL SIDE JUNCTION BLOCK RH (MULTIPLEX NETWORK BODY ECU) 

2.INSPECT SECURITY HORN ASSEMBLY
B108798
  1. Remove the security horn.

  1. Check operation of the horn.

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



NG
REPLACE SECURITY HORN ASSEMBLY
OK


3.CHECK WIRE HARNESS (MULTIPLEX NETWORK BODY ECU - SECURITY HORN ASSEMBLY)
B108799E02
  1. Disconnect the A41 ECU connector.

  1. Disconnect the A28 horn connector.

  1. Check the resistance of the wire harness side connectors.

    Standard resistance:
    Tester Connection
    Specified Condition
    A41-1 (SH) - A28-1
    Below 1 Ω
    A41-1 (SH) or A28-1 - Body sound
    10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS AND CONNECTOR
OK

REPLACE COWL SIDE JUNCTION BLOCK RH (MULTIPLEX NETWORK BODY ECU)