Diagnosis System

DIAGNOSIS SYSTEM

Inspect the battery voltage.
Battery voltage: 11 to 14 V

If voltage is below 11 V, recharge the battery before proceeding.

Check the DLC3.

The body ECU uses ISO 9141_2 for communication. The terminal arrangement of the DLC3 complies with SAEJ 1962 and matches the ISO 9141_2 format.

Verify the conditions listed in the table below:

Fig 1: Identifying DLC3 Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

DLC3 CONNECTOR TERMINALS SPECIFIED CONDITION

Symbols (Terminals No.)	Terminal Description	Condition	Specified Condition
SIL(7) - SG(5)	Bus "+" the	During communication	Pulse generation
SG(5) - Body ground	Signal ground	Always	Below 1
BAT(16) - Body ground	Battery positive	Always	11 to 14 V

HINT:

If the intelligent tester display shows UNABLE TO CONNECT TO VEHICLE when the cable of the intelligent tester is connected to the DLC3, the ignition switch is turned to the ON position and the tester is operate, there is a problem on either the vehicle side or the tester side.

If communication is normal when the tester is connected to another vehicle, inspect the DLC3 on the original vehicle.
If communication is still not possible when the tool is connected to another vehicle, the problem is probably in the tester itself, so consult the Service Department listed in the tester's instruction manual.