Generator runs but no AC output, E05 displayed on Scheppach controller

Safety first: Turn OFF the generator, disconnect battery negative, and ensure the unit cannot auto‑start. Never work on live AC circuits.

• Check main breaker: Open the front panel and verify the main AC circuit breaker is in the ON position. If tripped, reset once. If it trips again immediately under no load, suspect a short or internal alternator fault.
• Inspect output terminals: With power OFF, remove the cover over the alternator output lugs. Check that all Scheppach‑supplied cables are tight and show no signs of burning or discoloration. Tighten loose lugs.
• Check AVR connections: Locate the AVR module mounted on or near the alternator. Inspect the multi‑pin connector for corrosion or loose pins. Reseat the connector firmly.
• Test excitation voltage: With a qualified electrician and proper PPE, briefly run the generator and measure excitation voltage per the Scheppach service manual. If there is no excitation, the AVR or rotor winding may be faulty.
• Replace AVR if needed: If all wiring is intact and the rotor winding tests good (continuity within spec), replace the AVR with the correct Scheppach AVR model.

Because this involves high voltage, if you are not experienced with electrical testing, contact a licensed technician.