Is there a fuse on a garage door opener?

Yes, many garage door openers do have a fuse or a circuit protection device on the logic board, although it may not look like a traditional glass fuse you can easily replace. Most modern LiftMaster, Chamberlain, Craftsman, and Genie openers have a small automotive-style blade fuse or a resettable fuse or a fuse link soldered onto the logic circuit board inside the motor head unit on the ceiling. Its purpose is to protect the low-voltage circuits that power the safety sensors, wall control, and light from power surges, short circuits in the bell wire, or wiring mistakes. If you have a short in the sensor wiring, such as a staple through the wire or chewed wire that touches together, the fuse will blow to prevent damage to the board. Symptoms of a blown fuse include both safety sensors having no lights, the wall control not working, and the opener not responding to remotes, even though the opener is plugged in and has AC power. Some boards have a replaceable fuse you can pull and check, often a 3 amp or 10 amp fuse, while others have a non-replaceable fuse that requires replacing the entire logic board. Older openers may have no user-serviceable fuse and rely on a thermal breaker. Always unplug the opener before inspecting the board.