Security Horn Circuit

THEFT DETERRENT: THEFT DETERRENT SYSTEM (w/ Smart Key System): Security Horn Circuit

Security Horn Circuit

DESCRIPTION

When the theft deterrent system is changed from the armed state to the alarm sounding state, the certification ECU (smart key ECU assembly) controls the security horn.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - ENGINE ROOM JUNCTION BLOCK)




(a) Disconnect the D39 ECU connector.
(b) Connect the negative battery to the D39 ECU connector.
(c) Check operation of the security horn.
OK:






NG -- INSPECT SECURITY HORN ASSEMBLY
OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
2. INSPECT SECURITY HORN ASSEMBLY




(a) Remove the security horn assembly Removal.
(b) Check operation of the horn.
OK:






NG -- REPLACE SECURITY HORN ASSEMBLY
OK -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (ENGINE ROOM JUNCTION BLOCK ASSEMBLY - SECURITY HORN ASSEMBLY)




(a) Disconnect the 2A engine room junction block assembly connector and A15 security horn connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
4. CHECK HARNESS AND CONNECTOR (BATTERY - ENGINE ROOM JUNCTION BLOCK ASSEMBLY)




(a) Disconnect the 2G engine room junction block assembly connector.
(b) Measure the voltage on the relay block side according to the value(s) in the table below.
Standard voltage:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
5. CHECK HARNESS AND CONNECTOR (ENGINE ROOM JUNCTION BLOCK ASSEMBLY - CERTIFICATION ECU)
(a) Disconnect the 2D engine room junction block assembly connector.
(b) Disconnect the D39 ECU connector.
(c) Measure the resistance according to the value(s) in the table below.





Standard resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE ENGINE ROOM JUNCTION BLOCK ASSEMBLY