Symptoms
- Engine runs smoothly but nothing plugged in gets power
- Outlets show no voltage on a meter
- Breaker on the generator is tripped
- Generator hasn't been used in a long time
Likely causes
- CommonTripped circuit breaker on the generatorOverload or a short can trip the built-in breaker.
- CommonLoss of residual magnetism (for older non-inverter generators)Generators that sit unused for a long time can lose the magnetism needed to generate voltage.
- PossibleBlown fuse or faulty outletA specific outlet or internal fuse can fail while the engine itself is fine.
- PossibleFaulty AVR (automatic voltage regulator)This component regulates output voltage and can fail over time.
- PossibleBad connected device or cord, not the generatorTesting with a different device rules out the generator as the cause.
What to do
- Check and reset any tripped breakers on the generator control panel.
- Test outlets with a different device or a plug-in voltage tester to confirm no output.
- For older brushed generators, try 'flashing the field' per the owner's manual to restore residual magnetism (a brief 12V battery connection to the outlet, done only per manufacturer instructions).
- Check for a blown internal fuse and replace it if the manual identifies one.
- Inspect the extension cord and device you're plugging in on a different generator or outlet to rule them out.
- Let the generator run under no load for a few minutes to see if voltage builds.
- If output is still absent, the AVR or windings likely need professional testing.
Tools and parts
- Multimeter
- Owner's manual
Generator AVR (automatic voltage regulator)Search: “generator AVR replacement”
When to call a pro
If flashing the field doesn't restore output or the generator is an inverter type, a small-engine or generator repair shop can test the electrical components.
Safety
Use caution
Never operate a generator indoors or in an enclosed space; carbon monoxide from generator exhaust can be deadly. Keep it outdoors, away from windows and doors.