Buy OEM Lexus Part # 8949130061 (89491-30061, 8949130060). Engine Oil Level Sensor. Engine Oil Level Sensor - Repair or Replace If your engine oil level sensor has failed, it will usually provide

SENSOR, ENGINE OIL LEVEL

Fits GS 250, GS 300, GS 350, GS 450h, GS 460, IS 250, IS 250C, IS 350, IS 350C, RC 350

Engine Oil Level Sensor - Repair or Replace
If your engine oil level sensor has failed, it will usually provide a "false positive," meaning it will incorrectly report that your engine oil is low even if it isn’t. This can lead to some operators adding more oil than is necessary to the engine, which causes damage to major systems. Whether you suspect the oil level sensor or not, a technician should diagnose the fault in your Lexus to prevent engine damage.