Diagnosis System

DESCRIPTION
Power door lock control system data can be read through the Data Link Connector 3 (DLC3) of the vehicle. When the system seems to be malfunctioning, use the intelligent tester to check for malfunctions and perform repairs.

CHECK DLC3

The vehicle's ECU uses ISO 9141-2 for communication.
The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 9141-2 format.

Fig 1: Identifying DLC3 Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

DLC3 TERMINAL DESCRIPTION TABLE

Symbols (Terminal No.)	Terminal Description	Condition	Specified Condition
SIL (7) - SG (5)	Bus "+" line	During transmission	Pulse generation
CG (4) - Body ground	Chassis ground	Always	Below 1 -->
SG (5) - Body ground	Signal ground	Always	Below 1 -->
BAT (16) - Body ground	Battery positive	Always	11 to 14 V
CANH (6) - CANL (14)	HIGH-level CAN bus line	Ignition switch OFF	54 to 67 -->
CANH (6) - Battery positive	HIGH-level CAN bus line	Ignition switch OFF	1 M--> or higher
CANH (6) - CG (4)	HIGH-level CAN bus line	Ignition switch OFF	3 k--> or higher
CANL (14) - Battery positive	LOW-level CAN bus line	Ignition switch OFF	1 M--> or higher
CANL (14) - CG (4)	LOW-level CAN bus line	Ignition switch OFF	3 k--> or higher

HINT:

If the display shows a communication error message after connecting the intelligent tester to the DLC3 and turning the ignition switch to the ON position, there is a problem with either the vehicle or the intelligent tester.

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