Controller shows E20 and the generator shuts down during cranking or immediately after start.

Safety: Isolate battery and ensure no automatic start. Do not crank repeatedly to avoid overheating the starter.

• Measure cranking voltage: Monitor battery voltage during a start attempt. A large drop indicates weak batteries or high resistance.
• Inspect cables: Check starter positive and negative cables for corrosion, loose lugs, or undersized conductors. Clean and tighten as needed.
• Check engine rotation: Attempt to rotate the engine manually at the crankshaft (if accessible) to ensure it is not seized.
• Test starter current draw: Use a clamp meter to measure starter current. Excessive current with slow cranking suggests a failing starter motor that should be replaced.
• Replace weak batteries: If batteries are old or fail a load test, replace them with the correct capacity specified by Himoinsa.