Diagnosis System

CHECK DLC3

The vehicle's ECU uses ISO 15765-4 for communication protocol. The terminal arrangement of the DLC3 complies with ISO 15031-3 and matches the ISO 15765-4 format.

Fig 1: Identifying DLC3 Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

DLC3 TERMINALS REFERENCE

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

CANH (6) - CANL (14)

CAN bus line

Ignition switch OFF⁽¹⁾

54 to 69 Ω

CANH (6) - CG (4)

HIGH-level CAN bus line

Ignition switch OFF⁽¹⁾

200 Ω or higher

CANL (14) - CG (4)

LOW-level CAN bus line

Ignition switch OFF⁽¹⁾

200 Ω or higher

CANH (6) - BAT (16)

HIGH-level CAN bus line

Ignition switch OFF⁽¹⁾

6 kΩ or higher

CANL (14) - BAT (16)

LOW-level CAN bus line

Ignition switch OFF⁽¹⁾

6 kΩ or higher

NOTE:

⁽¹⁾	Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the ignition 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 intelligent tester to the DLC3, turn the ignition switch to the ON position and attempt to use the intelligent tester. If the screen displays a communication error message, a problem exists in the vehicle side or tester side.
HINT:
- If communication is normal when the tool is connected to another vehicle, inspect the DLC3 on the original vehicle.
- If communication is still impossible when the tool is connected to another vehicle, the problem is probably in the tool itself. Consult the service department listed in the tool's instruction manual.

Fig 2: Connecting Intelligent Tester To DLC3

INSPECT BATTERY VOLTAGE
1. Check the battery voltage.
  Standard voltage: 11 to 14 V
  
  If the voltage is below 11V, replace the battery before proceeding.
CHECK DIAGNOSIS
1. Turn the ignition switch ON.
2. Operate the driver side switch of the master switch.
3. Check the blinking pattern of the AUTO light as shown in the illustration.
  
  Fig 4: Identifying AUTO Light Blinking Pattern
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  1. If pattern (A) is displayed, reset power window regulator motor.
  2. If pattern (B) or (C) is displayed, check the wire harness.
  3. If the normal pattern is displayed, replace the multiplex network master switch.