Circulation or drain pump error, machine may not wash or rinse correctly

Safety first: Disconnect power and be prepared for water spillage when opening pump areas.

• Clean drain pump: Follow the steps for F11 to clean the drain pump filter and impeller.
• Check circulation pump (if fitted): Access the circulation pump under the tub. Inspect for obstructions such as lint or small objects.
• Test pump operation: During a wash cycle, listen for pump operation. If silent or humming only, the pump may be seized or burned out.
• Electrical tests: With power off, measure pump coil resistance and check for shorts to ground. Replace the pump if readings are out of spec.
• Control board: If pumps test good but F78 persists, the control board's pump driver circuit may be faulty and needs professional diagnosis.