Generator starts then quickly shuts down with LOW OIL PRESSURE alarm; may not crank again until reset.

Safety first: Place the controller in OFF, open the main breaker, and allow the engine to cool. Do not repeatedly attempt to start with a low oil pressure alarm.

• Check oil level: Use the dipstick to verify oil level with the unit on level ground. Top up with Guardian-approved engine oil to the full mark, but do not overfill.
• Inspect for leaks: Look around the oil filter, drain plug, and crankcase gasket for fresh oil. Tighten the oil filter and drain plug if seeping is observed, following torque specs.
• Replace oil filter: If the unit is due for service or the filter appears damaged, replace the oil filter with a Guardian-compatible filter and perform a full oil change.
• Check oil pressure switch wiring: Locate the oil pressure switch on the engine block. Ensure the connector is tight and wires are intact. A shorted or open switch can falsely trigger the alarm.
• Reset and test: After correcting oil level and leaks, clear the alarm by switching to OFF for 30 seconds, then back to AUTO and run a test. If LOW OIL PRESSURE persists, have a technician test actual oil pressure and replace the switch or repair the engine as needed.