Generator starts but immediately shuts down after a few seconds with no specific code; controller may show generic shutdown.

Safety first: Keep the generator isolated from load while diagnosing. Avoid repeated start attempts without addressing possible fuel or lubrication issues.

• Observe fuel lines: Watch transparent fuel lines (if fitted) for air bubbles as the engine runs. Bleed the system again if air is present.
• Check oil pressure switch timing: Use a mechanical gauge to confirm that oil pressure rises quickly after start. Replace the oil pressure switch if it opens at normal pressure.
• Inspect run relay: In the SDMO control panel, locate the engine run/hold relay. Check for loose connections or burnt contacts and replace if unreliable.
• Review safety inputs: Verify that all safety switches (coolant level, emergency stop, door switches) are correctly wired and not intermittently opening.