Security Horn Circuit

THEFT DETERRENT: THEFT DETERRENT SYSTEM: Security Horn Circuit
- Security Horn Circuit

DESCRIPTION

When the theft deterrent system is operating, the relay in the multiplex network body ECU turns on and off in a cycle of 0.4 seconds, causing the security horn to sound.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. PERFORM ACTIVE TEST USING TECHSTREAM

(a) Connect Techstream (with CAN VIM) to the DLC3.

(b) Turn the ignition switch on (IG).

(c) Press Techstream main switch on.

(d) Select the item below in the Active Test and then check that the indicator operates.

Body No. 5:





OK:

The security horn sounds or stops correctly when operating it through Techstream.

NG -- INSPECT FUSE (S-HORN)

OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

2. INSPECT FUSE (S-HORN)

(a) Remove the S-HORN fuse from the engine room R/B and J/B.

(b) Check the resistance.

Standard resistance:

Below 1 Ohms

NG -- REPLACE FUSE
OK -- Continue to next step.

3. INSPECT SECURITY HORN ASSEMBLY

(a) Check operation of the horn.





Standard resistance:





NG -- REPAIR OR REPLACE SECURITY HORN ASSEMBLY
OK -- Continue to next step.

4. CHECK WIRE HARNESS (ENGINE ROOM J/B ASSEMBLY - SECURITY HORN ASSEMBLY)

(a) Disconnect the 1B J/B connector.





(b) Disconnect the A18 horn connector.

(c) Check the resistance between the wire harness side connectors.

Standard resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

5. CHECK WIRE HARNESS (ENGINE ROOM J/B - BATTERY)

(a) Disconnect 1F J/B connector.





(b) Measure the voltage of the wire harness side connector.

Standard voltage:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE ENGINE ROOM JUNCTION BLOCK ASSEMBLY