Diagnosis System

DESCRIPTION
The network gateway ECU controls the functions of the Multiplex Communication System (MPX) of the vehicle. Data of the MPX and the Diagnostic Trouble Codes (DTCs) can be read in the Data Link Connector 3 (DLC3) of the vehicle.

CHECK DLC3

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

Fig 1: Identifying DLC3 Connectors Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

VOLTAGE AND RESISTANCE SPECIFICATION

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 Ω
SG (5) - Body ground	Signal ground	Always	Below 1 Ω
BAT (16) - Body ground	Battery positive	Always	11 to 14 V

HINT:

Connect the cable of the Techstream to the DLC3, turn the ignition switch ON and attempt to use the tester. If the screen displays the message UNABLE TO CONNECT TO VEHICLE, there is a problem either with the vehicle or the Techstream.

If communication is normal when the Techstream (with CAN VIM) is connected to another vehicle, inspect the DLC3 on the original vehicle.

If communication is still impossible when the Techstream is connected to another vehicle, the problem is probably in the Tecshtream itself.