Generator runs but displays UNDER VOLTAGE fault; home loads may drop out or transfer switch may not engage.

Safety first: Turn the generator OFF and open the main breaker. Do not operate with undervoltage as it can damage motors and electronics.

• Check air filter and fuel: Replace a clogged air filter and verify adequate fuel pressure to ensure the Centurion engine can reach full speed.
• Inspect alternator connections: Remove the alternator cover and check all stator and rotor leads for tightness and signs of overheating.
• Test no-load voltage: Run the generator in manual mode with no load and measure output. If voltage is still low, the AVR or rotor excitation may be failing.
• Reduce load: If undervoltage only occurs under heavy load, review which circuits are connected to the transfer switch and temporarily reduce nonessential loads.

When to call a technician: A technician should perform a full load test, check excitation voltage, and replace the AVR or repair alternator windings if required.