Dishwasher shows i51 and will not run the wash cycle; drain may still function.

Safety first: Unplug the dishwasher before accessing internal components.

• Check for blockages: Remove filters and inspect the sump for foreign objects that could jam the circulation pump impeller. A jammed pump can overload the triac.
• Listen during start: Start a program and listen: if the drain pump runs but there is no humming or water spraying, the circulation pump is not operating.
• Inspect wiring and connectors: Access the circulation pump (usually mounted on the sump). Check the connector for corrosion or burning and ensure the harness is intact.
• Test pump (advanced): With the pump disconnected and removed, measure its resistance and check for mechanical binding. Replace the pump if it is shorted or seized.
• Control board repair: If a new pump does not resolve the issue, the main PCB triac is likely damaged and the board must be replaced or professionally repaired.