Diagnosis System
- DESCRIPTION
- The certification ECU controls the function of the smart key system on the vehicle. Data of the smart key system and the Diagnostic Trouble Code (DTC) can be read in the Data Link Connector 3 (DLC3) of the vehicle. When a malfunction occurs in the smart key system, even though the smart key system warning light does not turn on, DTCs can be checked.
When the system seems to be malfunctioning, use the intelligent tester to check for a malfunction and perform repairs.
- The certification ECU controls the function of the smart key system on the vehicle. Data of the smart key system and the Diagnostic Trouble Code (DTC) can be read in the Data Link Connector 3 (DLC3) of the vehicle. When a malfunction occurs in the smart key system, even though the smart key system warning light does not turn on, DTCs can be checked.
- CHECK DLC3
- The vehicle uses the ISO 15765-4 for communication protocol. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 15765-4 format.DLC3 CONNECTOR TERMINALS REFERENCE CHART
Symbol Terminal No. Name Reference terminal Result Condition SIL 7 Bus "+" line 5 - Signal ground Pulse generation During transmission CG 4 Chassis ground Body ground Below 1 Constant SG 5 Signal ground Body ground Below 1 Constant BAT 16 Battery positive Body ground 11 to 14 V Constant 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 engine switch on (IG) and attempt to use the intelligent tester. If the screen displays a communication error message, a problem may be on the vehicle side or tester side.
- When troubleshooting the smart key system using the intelligent tester with the engine switch off, connect the intelligent tester to the vehicle and repeat turning any of the courtesy light switches on and off until communication between the tester and the vehicle begins (the interval between ON and OFF should be less than 1.5 sec.).
- 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 may be in the tester itself. Consult the Service Department listed in the tester's instruction manual.
- The vehicle uses the ISO 15765-4 for communication protocol. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 15765-4 format.
- CHECK BATTERY VOLTAGE
- Check the battery voltage.
Voltage:
11 to 14 V
If the voltage is below 11 V, replace the battery before proceeding.
- Check the battery voltage.