DIAGNOSIS You’ve got a complete power failure. The most likely culprit is that the fan’s internal thermal fuse, a small safety device, has blown, which is a common failure point on this model.
FIX This requires getting inside the unit. First, unplug it. Remove the front and rear grilles by unsnapping them or removing the screws at the base. You’ll see the motor assembly. Look for a small, white ceramic fuse holder (usually near where the power cord enters) with two wires. Use a multimeter to check for continuity. If it’s blown, you’ll need to replace it with an identical thermal fuse (commonly 142°C / 287°F). Solder the new one in place, reassemble carefully, and test.
IF THAT DIDN'T WORK The issue could be the main power switch or a broken wire in the cord right where it enters the base. Check for any visible damage or loose connections on the circuit board behind the control panel.
HEADS UP Be extremely gentle with the plastic clips when taking the grilles off—they’re brittle and can snap. If you’re not comfortable with soldering, this is a job for a repair shop.