Vehicle Security Indicator Circuit Check

Vehicle Security Indicator Circuit Check

Description

- Vehicle security indicator is built in combination meter.
- Immobilizer system and vehicle security system conditions are indicated by blink or illumination of vehicle security indicator.

Component Function Check

1. CHECK FUNCTION

1 Perform "THEFT IND" in the "Active Test" mode with SDT.
2 Check vehicle security indicator operation.






Is the inspection result normal?
YES
Inspection End.
NO
Refer to "Diagnosis Procedure".

Diagnosis Procedure

Regarding Wiring Diagram information, refer to [Vehicle Security System: Wiring Diagram [King Cab] Vehicle Security System [King Cab] ] or [Vehicle Security System: Wiring Diagram [Crew Cab] Vehicle Security System [Crew Cab] ].

1. SECURITY INDICATOR LAMP ACTIVE TEST

With SDT

Check "THEFT IND" in "Active test" mode with SDT.
Without SDT
1 Disconnect BCM.
2 Check voltage between BCM harness connector M18 terminal 23 and ground.











Is the inspection result normal?
YES
Security indicator lamp is OK.
NO
GO TO 2

2. SECURITY INDICATOR LAMP CHECK

Check security indicator lamp condition.

Is the inspection result normal?
YES
GO TO 3
NO
Replace combination meter. Refer to [Combination Meter: Removal and Installation] Service and Repair.

3. CHECK HARNESS CONTINUITY

1 Turn ignition switch OFF.
2 Disconnect BCM and security indicator lamp connector.
3 Check continuity between BCM connector M18 (A) terminal 23 and combination meter connector M24 (B) terminal 39.











4 Check continuity between BCM connector M18 (A) terminal 23 and ground.






Is the inspection result normal?
YES
Check the following:

- 10 A fuse [No. 19, located in fuse block (J/B)]
- Harness for open or short between security indicator lamp and fuse
NO
Repair or replace harness.