Generator shuts down during operation and the controller displays E04.

Safety first: Turn OFF the generator, disconnect battery negative, and lock out automatic start. Moving parts can start unexpectedly.

• Inspect throttle linkage: Locate the throttle lever on the Lifan engine carburetor or throttle body. Manually move the linkage; it should move smoothly and return via the governor spring. Lubricate pivot points lightly and remove any debris or binding.
• Check governor actuator (if electronic): With the controller in test mode (refer to Lifan manual), command the actuator and observe movement. If it does not move or is erratic, check its connector and 12 V supply. Replace the governor actuator if it fails basic tests.
• Inspect speed sensor: Many Lifan standby units use a magnetic pickup near the flywheel. Ensure the sensor tip is clean and the air gap is set per spec (often 0.5–1.0 mm). Check resistance with a multimeter; replace the engine speed sensor if open or shorted.
• Verify governor settings: If you have a frequency meter, run the unit and check output frequency. If it exceeds 63 Hz (for 60 Hz models) before shutdown, the governor may be misadjusted. Adjust only according to Lifan service procedures; incorrect adjustment can damage the engine.
• Test under load: After repairs, run the generator and gradually apply load while monitoring frequency and for recurrence of E04.