Generator shuts down and displays E09 (Underfrequency / Engine Underspeed) while under load.

Safety first: Open the generator output breaker and building main breaker before adjusting any engine components. Keep hands clear of moving parts.

• Remove or reduce load: Disconnect nonessential loads and heavy appliances from the generator. Restart and monitor frequency (Hz) if your Pulsar display shows it. If frequency returns to normal (~60 Hz), the generator was overloaded.
• Inspect governor linkage: With the engine off, remove the side panel and locate the mechanical governor arm and linkage on the carburetor or throttle body. Ensure it moves freely without binding. Clean any dirt or rust and lightly lubricate pivot points.
• Check fuel filters: Replace the inline fuel filter if it appears dirty or if fuel flow seems restricted. For LPG/NG, inspect the regulator and hoses for kinks or icing.
• Observe engine speed: In MANUAL mode with no load, start the generator and listen for surging or low RPM. If the engine cannot reach rated speed, the electronic governor module or throttle actuator may be failing.

If E09 persists with proper load and clean fuel supply, governor calibration or module replacement may be required and should be performed by a qualified technician with frequency measurement tools.