Generac Generator Troubleshooting Guide

Engine surges and doesn’t run great?

  • Potential Causes:
    • Poor fuel quality
    • Loose filter/fuel lines
    • Failing injectors
    • Failing throttle actuator
    • Loose throttle actuator
    • Bad governor settings
    • Weak lift pump

Fuel Leak Sensor / 90% Fault

  • To test the sensor:
    Jump the sensor wires at HUIO
  • To fix Pull on the sensor wire to adjust the height.
  • Faults often occur after the generator is overfilled or has been running for many hours.

Back Panels with Hex Bolts Hard to Remove?

  • Use an impact wrench and only remove 3 out of 4 hex bolts per square piece for faster access.

WR Engine Stall

  • Force the generator to run by jumping power to the fuel shutoff solenoid or run relay circuit
  • Make sure generator isn’t losing prime
  • Change parameters (Start Detection RPM) in Genlink to allow more time for generator to start
  • Make sure Engine Run/Fuel Relay is powered

Radiator Removal

  • Remove both top covers and avoid removing the dogbox if possible.
  • The radiator unbolts from the front side inside the box, and comes out from the top.

Battery Chargers Keep Failing?

  • Check for corrosion and ensure all hot/neutral lugs are tight on the generator and breaker box.
  • You can replace the battery charger with an aftermarkt charger and retain the OEM connector.

Battery Charger GFCI Thrown?

  • This is usually caused by the battery heater. Unplug or replace the heater.

GFCI Thrown from Block Heater?

  • Reset the GFCI. The block heater is most likely still functional.

Coolant Sensor Not Working Properly?

  • The sensor must provide the correct ohm resistance to be recognized by the ECM. Jumping or leaving the circuit open won’t work.
  • Plastic sensors tend to work better for some reason.

Intermittent Low Oil Pressure Warning

  • Replace the oil pressure sensor and pinpoint test to J1? connector.