Generator runs but the controller shows E10 and the unit refuses to transfer load.

Safety first: Set the generator to OFF and disconnect the battery negative terminal. Lock out the ATS if possible.

• Check for mechanical binding: Inspect the throttle and governor linkage for sticking or interference. Ensure the return springs are intact and not stretched.
• Observe frequency: With a frequency meter or a multimeter with a Hz function, run the generator with no load and measure the frequency at the output. It should be close to 60 Hz. Large deviations indicate a governor problem.
• Inspect governor module connections: Locate the electronic governor module (if equipped) and verify all connectors are secure. Look for signs of overheating or moisture damage.
• Lightly load test: Apply a small load (e.g., 10–20% of rated kW) and observe if the frequency stabilizes. If the frequency remains unstable, the governor module or engine may need professional adjustment.

Frequency calibration typically requires specialized tools and and should be performed by a Firman-authorized technician.