THEFT DETERRENT SYSTEM > 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 (multiplex network body ECU) transmits a signal to cause the horns to sound at intervals of 0.4 seconds.

WIRING DIAGRAM


B272452E01


INSPECTION PROCEDURE

1.INSPECT HORNS
  1. Press the horn switch and check if the horns sound.

    Result:
    Result
    Proceed to
    Horns sound
    A
    Horns do not sound
    B



B
GO TO HORN SYSTEM (Click here)
A


2.PERFORM ACTIVE TEST 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 / Active Test.

  1. Perform the Active Test according to the display on the intelligent tester.

    Main Body (Main Body ECU (Multiplex Network Body ECU)) 
    Tester Display
    Test Part
    Control Range
    Diagnostic Note
    Vehicle Horn
    Vehicle horns
    ON / OFF
    -

    Result:
    Result
    Proceed to
    The vehicle horns do not sound when operated through the intelligent tester
    A
    The vehicle horns sound and stop correctly when operated through the intelligent tester
    B



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


3.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.


    B220581E05

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

    Standard Resistance:
    Tester Connection
    Condition
    Specified Condition
    2C-24 - MB-28 (HORN)
    Always
    Below 1 Ω
    2C-24 - 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

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