Diagnosis System

DESCRIPTION
The main body ECU controls the functions of the power door lock control system on the vehicle. Data of the power door lock control system and Diagnostic Trouble Code (DTCs) can be read in the Data Link Connector 3 (DLC3) of the vehicle.

When the system seems to be malfunctioning, use the Techstream to check for a malfunction and perform repairs.

CHECK DLC3

The vehicle's ECU uses the ISO 15765-4 communication protocol. The terminal arrangement of the DLC3 complies with ISO 15031-03 and matches the ISO 15765-4 format.

Fig 1: Identifying DLC3 Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

DLC3 CONNECTOR TERMINALS REFERENCE CHART

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

Signal ground

Always

Below 1 Ω

BAT (16) - Body ground

Battery positive

Always

10 to 14 V

CANH (6) - CANL (14)

CAN bus line

Power switch is OFF⁽¹⁾

54 to 69 Ω

CANH (6) - CG (4)

HIGH-level CAN bus line

Power switch is OFF⁽¹⁾

200 Ω or higher

CANL (14) - CG (4)

LOW-level CAN bus line

Power switch is OFF⁽¹⁾

200 Ω or higher

CANH (6) - BAT (16)

HIGH-level CAN bus line

Power switch is OFF⁽¹⁾

6 kΩ or higher

CANL (14) - BAT (16)

LOW-level CAN bus line

Power switch is OFF⁽¹⁾

6 kΩ or higher

⁽¹⁾	: Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the power switch, any other switches or the doors.

If the result is not as specified, the DLC3 may have a malfunction. Repair or replace the harness and connector.

Connect the cable of the Techstream to the DLC3, turn the power switch ON (IG) and attempt to use the tester. If the display indicates that a communication error has occurred, there is a problem either with the vehicle or with the tester.

HINT:

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 tester is connected to another vehicle, the problem may be in the tester itself. Consult the Service Department listed in the tester's instruction.