Control panel shows E16, generator runs but frequency is out of range (not 60 Hz)

Safety first: Disconnect all loads and open the main breaker. Use a frequency meter or multimeter with Hz function when adjusting.

• Check throttle linkage: With the engine off, move the governor arm and throttle lever through full travel. Lubricate any stiff joints and ensure the return spring is intact.
• Verify controller setting: In the control panel menu, confirm that the nominal frequency is set to 60 Hz (or your region's standard) and that engine speed parameters match the DuroMax specification.
• Adjust mechanical governor: On units with a mechanical governor, adjust the governor spring tension screw slightly while monitoring frequency at no load. Aim for about 61–62 Hz no‑load so it settles near 60 Hz under load. Follow the service manual procedure.
• Electronic actuator test: For electronic governors, observe the actuator movement during start. If it hunts or fails to respond, check its wiring and replace the actuator if necessary.
• Professional calibration: If you cannot stabilize frequency within spec, have a technician perform a full governor calibration and controller tuning.