Generator will not start in AUTO or MANUAL mode; control panel displays E01 immediately after a start attempt.

Safety first: Turn the generator to OFF, disconnect the battery negative cable, and ensure utility power is present so loads are not lost. Allow the engine to cool completely before working near the engine.

• Check oil level: Remove the dipstick on your All Power America standby generator engine. Wipe, reinsert fully, and check the level. Top up with the manufacturer-specified oil (typically SAE 10W-30 or as listed in your model manual) to the FULL mark. Do not overfill.
• Inspect for leaks: Look around the oil filter, drain plug, and crankcase gasket for fresh oil. Tighten the oil drain plug and oil filter by hand plus a small additional turn if they are seeping. Replace any damaged gasket or filter.
• Test the oil pressure switch: Locate the oil pressure switch on the engine block (usually near the oil filter). Disconnect its wire and check for continuity to ground with the engine off. On many models, the switch is normally closed to ground with no pressure. If it is open or intermittent, replace the oil pressure switch.
• Inspect wiring: Trace the oil pressure switch wire back to the All Power America control board. Look for chafed insulation, loose spade connectors, or corrosion at terminals. Clean and tighten all connections.
• Clear the code and retest: Reconnect the battery, set the controller to MANUAL, and attempt a start. If the engine starts and runs without E01 returning, switch back to AUTO.

Do not bypass the oil pressure switch for normal operation; running with low oil pressure can destroy the engine.