Lexus IS250 IS220d GSE20 ALE20 - ENGINE IMMOBILISER
ENGINE IMMOBILISER SYSTEM (for 2AD-FHV) - DIAGNOSIS SYSTEM
| DESCRIPTION |
Engine immobiliser system data and Diagnostic Trouble Codes (DTCs) can be read through the vehicle's Data Link Connector 3 (DLC3). In some cases, a malfunction may be occurring in the immobiliser system even though the security indicator is not illuminated. When the system seems to be malfunctioning, use the intelligent tester to check for malfunctions and perform repairs.
| CHECK DLC3 |
The vehicle uses ISO 15765-4 for communication protocol. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 15765-4 format.
| Symbols (Terminals No.) | Terminal Description | Condition | Specified Condition |
| SIL (7) - SG (5) | Bus "+" line | During transmission | Pulse generation |
| BAT (16) - Body ground | Battery positive | Always | 10 to 14 V |
| CG (4) - Body ground | Chassis ground | Always | Below 1 Ω |
| SG (5) - Body ground | Signal ground | Always | Below 1 Ω |
If the result is not as specified, the DLC3 may have a malfunction. Repair or replace the harness and connector.
- 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 screen displays a communication error message, 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 is probably in the tester itself. Consult the Service Department listed in the tester's instruction manual.
| INSPECT BATTERY VOLTAGE |
Measure the battery voltage.
- Standard voltage:
- 11 to 14 V
If the voltage is below 11 V, recharge or replace the battery before proceeding to the next step.