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

Safety first: Set the generator to OFF and disconnect battery negative. 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 Hz function, run the generator with no load and measure 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 frequency stabilizes. If frequency remains unstable, the governor module or engine may need professional adjustment.

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