THEFT DETERRENT SYSTEM > DIAGNOSIS SYSTEM

The multiplex network body ECU controls the functions of the theft deterrent system on the vehicle. Theft deterrent system data can be read in the Data Link Connector 3 (DLC3) of the vehicle. When the system seems to be malfunctioning, use the intelligent tester to check for a malfunction and perform repairs.

The vehicle's ECM uses the ISO 9141-2 (Euro-OBD)/ ISO 14230(M-OBD) communication protocol. The terminal arrangement of the DLC3 complies with ISO 15031-3 and matches the ISO 9141-2/ ISO 14230 format.

Symbol	Terminal No.	Name	Reference terminal	Result	Condition
SIL	7	Bus "+" line	5-Signal ground	Pulse generation	During transmission
CG	4	Chassis ground	Body ground	1 Ω or less	Always
SG	5	Signal ground	Body ground	1 Ω or less	Always
BAT	16	Battery positive	Body ground	9 to 14 V	Always

Connect the cable of the intelligent tester to the DLC3, turn the ignition switch ON and attempt to use the intelligent tester. If the screen displays a communication error message, a problem exists in the vehicle side or with the tester side.

1. If communication is normal when the tool is connected to another vehicle, inspect the DLC3 on the original vehicle.
   
2. If communication is still impossible when the tool is connected to another vehicle, the problem is probably in the tool itself. Consult the Service Department listed in the tool's instruction manual.