DIAGNOSIS Power is not reaching the printer's mainboard. This is almost always the external power supply (the brick on the cord) or a tripped internal fuse from a surge.
FIX Check the power supply and connections first.
1. Verify the power brick is firmly plugged into a working wall outlet and the cord is firmly connected to the brick and the printer.
2. Try a different wall outlet, bypassing power strips or surge protectors.
3. Look at the power brick. If it has a small light, see if it's lit. If no light on any outlet, the brick is dead and needs replacement (order Epson part number, don't use a generic).
4. If the brick has a light but the printer is dead, the issue is internal.
IF THAT DIDN'T WORK Unplug the printer for 60 full minutes. This can reset an internal thermal fuse. After an hour, plug it directly into the wall and try the power button again. If still dead, it requires professional repair.
HEADS UP Never use a third-party power supply with a different voltage or amperage rating. You can find the correct specs (24V DC) on the label of the original brick. Using the wrong one can fry the mainboard.