Novoferm garage door opener will not start; no lights or display, but mains supply is present.

Safety first: Only qualified persons should work on mains wiring. Disconnect power at the breaker before opening the unit.

Steps to try:

• Check outlet: Test the socket or circuit with another appliance to confirm power is present.
• Inspect mains cable: Verify that the Novoferm opener's plug and cable are intact and not damaged.
• Check internal connections: With power off, open the cover and ensure the mains wires are secure in the terminal block and that any internal fuse is intact.

If there is still no sign of life and the fuse and wiring are good, the internal power supply or transformer has failed and the control board or transformer must be replaced.