Lexus IS250 IS220d GSE20 ALE20 - MULTIPLEX COMMUNICATION
MULTIPLEX COMMUNICATION SYSTEM - DIAGNOSIS SYSTEM
| DESCRIPTION |
The gateway ECU controls the functions of the multiplex communication system on the vehicle. Data of the multiplex communication system and the Diagnostic Trouble Codes (DTC) can be read through the Data Link Connector 3 (DLC3) of the vehicle.
| CHECK DLC3 |
The vehicle uses ISO 9141-2 (Euro-OBD) as its communication protocol. The terminal arrangement of the DLC3 complies with ISO 15031-3 and matches the ISO 9141-2 format.
Verify the conditions listed in the table below:
| 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 |
If the result is not as specified, the DLC3 may have a malfunction. Repair or replace the harness and connector.
Intelligent tester
- HINT:
- Connect the cable of the intelligent tester to the DLC3, turn the engine 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.
If communication is normal when the tester is connected to another vehicle, inspect the DLC3 of 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 manual.
| INSPECT BATTERY VOLTAGE |
If the voltage is below 11 V, recharge or replace the battery before proceeding.
- Standard voltage:
- 11 to 14 V
LEXUS IS250, IS220d / GSE20 ALE20