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) controls the security horn.

WIRING DIAGRAM

A0042KHE06

INSPECTION PROCEDURE

Note

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

PROCEDURE


  1. PERFORM ACTIVE TEST USING GTS


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

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

    5. Select the item below in the Active Test and then check that the security horn assembly operates.

      Main Body
      Tester Display Test Part Control Range Diagnostic Note
      Security Horn Security horn ON / OFF -
      OK
      The security horn assembly sounds and stops correctly when operated through the GTS.

    NG

    INSPECT SECURITY HORN ASSEMBLY Click here

    OK

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

  2. INSPECT SECURITY HORN ASSEMBLY


    1. A0043UT

      Remove the security horn assembly Click here.

    2. Check the operation of the security horn assembly.

      OK
      Auxiliary Battery Connection Specified Condition
      Auxiliary battery positive (+) → Terminal 1 Horn sounds
      Auxiliary battery negative (-) → Horn body

    NG

    REPLACE SECURITY HORN ASSEMBLY Click here

    OK

  3. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY


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

      A0041HNE25

    2. Disconnect the 2C 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
      2C-39 - A-17 (SH) Always Below 1 Ω
      Text in Illustration
      *a

      Component without harness connected

      (Instrument Panel Junction Block Assembly)

      		 - -

    NG

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here

    OK

  4. INSPECT S-HORN RELAY


    1. A0041HP

      Remove the S-HORN relay from the engine room relay block and junction block assembly.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3 - 5 Auxiliary battery voltage supplied between terminals 1 and 2 Below 1 Ω
      3 - 5 Auxiliary battery voltage not supplied between terminals 1 and 2 10 kΩ or higher

    NG

    REPLACE S-HORN RELAY

    OK

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


    1. A0043ZEE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Engine Room Relay Block and Junction Block Assembly (S-HORN Relay))

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      1 - Body ground Power switch off 11 to 14 V
      5 - Body ground Power switch off 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. A0043ZEE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Engine Room Relay Block and Junction Block Assembly (S-HORN Relay))

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      2 - 2C-39 Always Below 1 Ω
      2C-39 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. A0043ZEE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Engine Room Relay Block and Junction Block Assembly (S-HORN Relay))

      Disconnect the A59 security horn assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A59-1 - 3 Always Below 1 Ω
      A59-1 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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