Theft Deterrent System Security Horn Circuit


DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

PERFORM ACTIVE TEST USING INTELLIGENT TESTER (SECURITY HORN)

INSPECT S-HORN RELAY

INSPECT SECURITY HORN ASSEMBLY

CHECK HARNESS AND CONNECTOR (ENGINE ROOM RELAY BLOCK - MAIN BODY ECU AND SECURITY HORN)

THEFT DETERRENT SYSTEM - Security Horn Circuit


DESCRIPTION

When the theft deterrent system is in the alarm sounding state, the main body ECU outputs a signal repeatedly at 0.4 second intervals, causing the security horn assembly to sound.

WIRING DIAGRAM


Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Theft Deterrent Keyless Entry.Entry And Start System (For Entry Function).Theft Deterrent System Security Horn Circuit


INSPECTION PROCEDURE

NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
1.PERFORM ACTIVE TEST USING INTELLIGENT TESTER (SECURITY HORN)

  1. Operate the intelligent tester according to the steps on the display and select Active Test (LandCruiser RM000000W0S036X.html).

    Main Body
    Tester Display
    		Test Part
    		Control Range
    		Diagnostic Note
    Security Horn
    		Security horn
    		ON/OFF
    		-
    OK:
    Security horn operates normally.


NG
Go to step 2
OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE (LandCruiser RM000002TGC02DX.html)

2.INSPECT S-HORN RELAY


    Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Theft Deterrent Keyless Entry.Entry And Start System (For Entry Function).Theft Deterrent System Security Horn Circuit

  1. Remove the S-HORN relay from the engine room relay block.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    3 - 5
    		Battery voltage is not applied to terminals 1 and 2
    		10 kΩ or higher
    3 - 5
    		Battery voltage is applied to terminals 1 and 2
    		Below 1 Ω


NG
REPLACE S-HORN RELAY
OK


3.INSPECT SECURITY HORN ASSEMBLY

  1. Remove the security horn (LandCruiser RM000002PLR02ZX.html).

  1. Apply battery voltage to the horn connector and check the operation of the horn.

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


NG
REPLACE SECURITY HORN ASSEMBLY (LandCruiser RM000002PLR02ZX.html)
OK


4.CHECK HARNESS AND CONNECTOR (ENGINE ROOM RELAY BLOCK - MAIN BODY ECU AND SECURITY HORN)

  1. Remove the S-HORN relay from the engine room relay block.

  1. Remove the main body ECU (LandCruiser RM000003WBO05FX.html).

  1. Disconnect the A26 horn connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    Relay block S-HORN relay terminal 1 - A-17 (SH)
    		Always
    		Below 1 Ω
    Relay block S-HORN relay terminal 3 - A26-1
    		Always
    		Below 1 Ω
    A-17 (SH) - Body ground
    		Always
    		10 kΩ or higher
    A26-1 - Body ground
    		Always
    		10 kΩ or higher

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

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    Relay block S-HORN relay terminal 2 - Body ground
    		Always
    		11 to 14 V
    Relay block S-HORN relay terminal 5 - Body ground
    		Always
    		11 to 14 V


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) (LandCruiser RM000003WBO05FX.html)