Diagnosis System

CHECK DLC3

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

Fig 1: Checking DLC3

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

TERMINAL WIRING 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 hand-held tester to the DLC3, turn the ignition switch ON and attempt to use the tester. If the display informs that a communication error has occurred, there is a problem either with the vehicle or with the tester.

If communication is normal when the hand-held tester is connected to another vehicle, inspect the DLC3 on the original vehicle.

If communication is not still possible 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 instruction manual.

Fig 2: Connecting Hand-Held Tester To DLC3

INSPECT BATTERY VOLTAGE
Standard: 11 to 14 V

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