Safety first: Unplug the dryer before opening any panels. Internal fuses should only be replaced with identical types and ratings.

Check outlet and cord: Test the wall outlet with another appliance. Inspect the SMEG dryer power cord for damage and ensure it is firmly plugged in.
Inspect mains filter: Access the mains interference filter where the power cord enters the dryer. Check for burnt components or loose terminals. Replace the filter if damaged.
Check internal fuse: On some models, the main control board has a replaceable fuse. Inspect and test this fuse with a multimeter. Replace only with the same rating if blown, and investigate why it failed.
On/off switch and relay: Test the on/off switch for continuity when pressed. If the switch or power relay on the board is faulty, replace the affected component or the entire board.
Reassemble and test: After repairs, reconnect power and verify that the display powers up and E20 is cleared.

Dryer shows E20; may not respond to any buttons and display may be blank or frozen.

Possible Causes