Door will not open or close at all, no display or lights on operator

Safety first: Work on mains circuits only if you are qualified. Otherwise, call an electrician.

Step-by-step:

• Check supply: Verify that other devices on the same circuit work. Reset the breaker or replace the fuse in the distribution board if tripped.
• Inspect plug and cable: If the Hormann operator is plugged into a socket, test the socket with another appliance. Check the operator's power cable for cuts or crushed sections.
• Internal fuse: With power off, open the operator cover and locate the internal fuse on the control board. Replace only with the same rating.
• If still dead: The control board power supply or transformer is likely defective and the board should be replaced.