Controller displays 'Freq Error', 'High Freq', or 'Low Freq'; transfer switch may refuse to transfer.

Safety First: Turn OFF the generator breaker before testing. Avoid adjusting governor settings beyond basic checks unless trained.

• 1. Verify engine speed: Use a frequency meter or multimeter with Hz function to measure output frequency at no load. It should be near 60 Hz.
• 2. Inspect governor linkage: Ensure the governor arm and throttle move freely and are not binding. Do not change factory governor screw settings.
• 3. Check sensing leads: Confirm the stator sensing wires to the controller are tight and undamaged.
• 4. Monitor under load: Apply a moderate load and observe frequency. Large drops indicate governor or fuel issues; large rises indicate overspeed.
• 5. If frequency remains unstable: Professional adjustment of the governor or replacement of the control board may be required.