Generator will not start, control panel shows E01 shortly after cranking attempt

Safety first: Switch the generator OFF, set the engine switch to 0, disconnect the spark plug cap and isolate the unit from any transfer switch or building wiring before working on it.

• Check oil level: Place the Einhell standby generator on level ground. Remove the oil filler cap/dipstick. Wipe, reinsert without screwing, then check the level. Top up with the oil grade specified in the Einhell manual (typically 10W‑30 or 15W‑40 for many models) up to the upper mark.
• Inspect for leaks: Look around the crankcase, oil drain plug, and oil filter (if fitted) for fresh oil. Tighten the drain plug and filler cap. Replace any damaged sealing washer.
• Reset and test: Reconnect the spark plug cap, turn the engine switch to ON, and attempt a restart. If E01 clears and the engine runs, monitor for further oil loss.
• Check low‑oil sensor wiring: If the oil level is correct but E01 persists, locate the low‑oil sensor wire on the crankcase (usually a single wire going to the engine block). Inspect for broken insulation, loose connectors, or corrosion. Clean and reseat the connector.
• Sensor test (advanced): With the engine OFF and spark plug disconnected, temporarily disconnect the low‑oil sensor wire from the harness. Attempt to start. If the engine now starts, stop it immediately and replace the low‑oil sensor—do not operate permanently with the sensor bypassed.

If the error remains after these checks, have an authorized Einhell service center test the sensor circuit and control module.