Diagnosis System

DESCRIPTION
1. Power door lock control system data can be read in the Data Link Connector 3 (DLC3) of the vehicle. When the system seems to be malfunctioning, use the intelligent tester to check for malfunctions and perform repairs.

CHECK DLC3

The vehicle's ECM uses ISO 9141-2 for communication.

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

Fig 1: Identifying DLC3 Connector Terminals

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

TESTER CONNECTION SPECIFIED CONDITION

Tester Connection	Condition	Specified Condition
7 (Bus + line) - 5 (Signal ground)	During communication	Pulse generation
4 (Chassis ground) - Body ground	Constant	Below 1
5 (Signal ground) - Body ground	Constant	Below 1
16 (B+) - Body ground	Constant	9 to 14 V

HINT:

Connect the cable of the intelligent tester to the DLC3, turned the ignition switch ON and attempt to use the intelligent tester. If the screen displays UNABLE TO CONNECT TO VEHICLE, a problem exists in the vehicle side or tester side.

If communication is normal when the tester is connected to another vehicle, inspect the DLC3 of the original vehicle.
If communication is still impossible 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 manual.

Check the battery voltage.

INSPECT BATTERY VOLTAGE
1. Inspect the battery voltage.
  Voltage:
  
  11 to 14 V
  
  If voltage is below 11 V, recharge the battery before proceeding.