Generator runs but the control panel shows E09 and the unit may shut down when loads are applied.

Safety first: Turn the generator OFF, open the generator output breaker, and lock out the ATS. Verify with a meter that no voltage is present before touching wiring.

• Check output connections: Inspect the main output lugs inside the Genergy alternator junction box. Tighten any loose connections and look for signs of overheating or discoloration.
• Inspect AVR wiring: Locate the Automatic Voltage Regulator module in the alternator or control compartment. Ensure all plug‑in connectors are fully seated and free of corrosion.
• Measure no‑load voltage: With a qualified electrician, start the generator and measure line‑to‑line and line‑to‑neutral voltages at the generator terminals. If voltage is very low or zero, the AVR or excitation circuit may have failed.
• Check brushes and slip rings (if applicable): On brush‑type Genergy alternators, remove the brush holder and inspect brushes for wear. Clean slip rings with fine emery cloth and replace worn brushes.
• Replace AVR if defective: If excitation voltage is absent and stator windings test good, replace the AVR with a Genergy‑approved unit and retest.

Because of shock and arc‑flash hazards, AC voltage troubleshooting should be performed only by qualified personnel.