Controller displays F15 Oil Level Sensor Fault; generator may not start or may ignore low oil level.

Safety first: Turn the generator to OFF and allow the engine to cool before working around the oil pan.

• Verify oil level: First confirm that the engine oil level is correct using the dipstick. Correct any low level condition.
• Inspect sensor connection: Locate the oil level sensor on the side of the oil pan. Ensure the connector is fully seated and free of oil contamination. Clean and reconnect.
• Check wiring continuity: With the connector unplugged, test continuity from the sensor plug back to the controller terminals. Repair any open or shorted wires.
• Replace sensor: If wiring is intact but F15 persists, replace the oil level sensor with the Siemens-specified part. Use a drain pan to catch any oil that may escape when removing the sensor.
• Controller configuration: Verify in the controller settings that the oil level sensor input is enabled or disabled according to your model. Incorrect configuration can cause false F15 alarms.