THEFT DETERRENT SYSTEM 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 horns to sound at intervals of 0.4 seconds.

WIRING DIAGRAM

B004L3ME07

CAUTION / NOTICE / HINT

Note


  • Before replacing the main body ECU (multiplex network body ECU), refer to Service Bulletin.*


    • *: w/ Smart Entry and Start System

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

  • The vehicle battery supplies power to the main body ECU (multiplex network body ECU) via the door control battery. Therefore, before performing this troubleshooting procedure, make sure to perform an on-vehicle inspection to confirm that the main body ECU (multiplex network body ECU) power source circuit is normal.*

    Click here


    • *: w/ Door Control Battery

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. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY


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

      Click here

      B004HTAC09
      *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-27 - MB-28 (HORN) Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

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

    NG

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here