THEFT DETERRENT SYSTEM Security Horn Circuit

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 security horn to sound at intervals of 0.4 seconds.

WIRING DIAGRAM

A012MY8E01

CAUTION / NOTICE / HINT

Note

Inspect the fuses for circuits related to this system before performing the following procedure.

PROCEDURE


  1. PERFORM ACTIVE TEST USING GTS (SECURITY HORN)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

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

    5. Perform the Active Test according to the display on the GTS.


      Body Electrical > Main Body > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Security Horn Security horn OFF/ON -

      Body Electrical > Main Body > Active Test
      Tester Display
      Security Horn
      OK
      The security horn assembly sounds and stops correctly when operated through the GTS.
      Result
      Proceed to
      OK
      NG

    OK

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

    NG

  2. INSPECT SECURITY HORN ASSEMBLY


    1. A012GOB

      Remove the security horn.

      Click here

    2. Check the operation of the security horn assembly.

      OK
      Battery Connection Specified Condition

      Battery positive (+) → Terminal 1

      Battery negative (-) → Security horn body

      		 Horn sounds
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE SECURITY HORN ASSEMBLY Click here

    OK

  3. INSPECT S-HORN RELAY


    1. A012JHIC02
      *1 S-HORN Relay

      Remove the S-HORN relay from the No. 4 relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3 - 5 When battery voltage is not applied between terminals 1 and 2 10 kΩ or higher
      3 - 5 When battery voltage is applied between terminals 1 and 2 Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE S-HORN RELAY

    OK

  4. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY


    1. Remove the main body ECU (multiplex network body ECU).

      Click here

      A012KVLC01
      *a

      Component without harness connected

      (Instrument Panel Junction Block Assembly)

      		 - -

    2. Disconnect the 3C instrument panel junction block assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3C-40 - MB-17 (SH) Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here

    OK

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


    1. A012GXFC01
      *1 No. 4 Relay Block

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      No. 4 relay block S-HORN relay terminal 1 - Body ground Always 11 to 14 V
      No. 4 relay block S-HORN relay terminal 5 - Body ground Always 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. A012GXFC01
      *1 No. 4 Relay Block

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      No. 4 relay block S-HORN relay terminal 3 - A122-1 Always Below 1 Ω
      No. 4 relay block S-HORN relay terminal 3 - Body ground Always 10 kΩ or higher
      A122-1 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  7. CHECK HARNESS AND CONNECTOR (S-HORN RELAY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)


    1. A012GXFC02
      *1 No. 4 Relay Block

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      No. 4 relay block S-HORN relay terminal 2 - 3C-40 Always Below 1 Ω
      No. 4 relay block S-HORN relay terminal 2 - Body ground Always 10 kΩ or higher
      3C-40 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

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

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR