Generator runs but produces no power

Symptoms

• Engine runs smoothly but nothing plugged in gets power
• No voltage reading at the outlets with a meter
• Worked fine before, then suddenly no output
• Some outlets work, others don't

Likely causes

• CommonTripped internal circuit breakerOverloading or a short can trip a breaker on the panel that's easy to overlook.
• CommonGenerator lost residual magnetism (common after long storage)Conventional generators need a small residual magnetic field to begin generating; long periods unused can let this fade, a process called 'flashing the field' can restore it.
• PossibleBad GFCI outlet on the generator itselfMany portable generators have built-in GFCI outlets that can trip or fail, cutting power to just those receptacles.
• PossibleFaulty AVR (automatic voltage regulator)This component regulates output voltage; failure can cause zero or very low output.
• PossibleBlown fuse or failed capacitor inside the generator headEspecially relevant on inverter generators, which use more electronics.

What to do

1. Check and reset any tripped breakers on the generator's control panel.
2. Reset any GFCI outlets on the generator itself by pressing their reset button.
3. Test a single, known-good device (like a work light) directly at each outlet with the engine at operating speed.
4. Use a multimeter at the outlets to check for any voltage output, even low, which helps distinguish a total failure from a regulation problem.
5. If the generator hasn't been used in a long time and shows zero output, look up your model's 'residual magnetism' or 'flashing the field' procedure in the owner's manual, since this is a known issue on some conventional generators.
6. Check the owner's manual for an accessible fuse related to the outlets or control panel and inspect it.
7. If none of this restores output, the AVR or generator head likely needs professional testing and possible replacement.

Tools and parts

• Multimeter

When to call a pro

If breakers, GFCIs, and basic checks don't restore output, have a small-engine or generator repair shop test the AVR and generator head.

Safety