Dishwasher displays E20; unit may be unusually noisy and may not circulate water correctly.

Safety first: Turn off power and allow the dishwasher to cool before working underneath.

Step-by-step checks:

• Listen for abnormal sounds: Grinding, squealing, or repeated clicking during wash indicates motor or pump issues.
• Check for obstructions: Remove filters and inspect the sump for foreign objects that could jam the impeller.
• Access circulation pump: From below, inspect the pump for leaks, overheating discoloration, or a burnt smell.
• Impeller movement: With power off, gently try to rotate the impeller. If it is stiff or locked, the pump should be replaced.
• Persistent E20: If a new pump still triggers E20, the control board motor driver may be defective and require replacement.

Warning: Do not continue running the dishwasher with a noisy or overheating motor; this can cause further damage or fire risk.