Diagnosis
This is almost always a power supply issue, not a dead printer. The external power brick for the ET-2850 can fail, or the connection at the back of the printer can work loose.
How to Fix It
First, check the obvious. Trace the power cable from the wall to the large black power adapter brick, and from the brick to the printer. Make sure every connection is pushed in firmly at both the wall, the brick, and the printer's DC-in port. Try a different wall outlet that you know works. Listen closely at the power brick for a very faint hum when plugged in.
If That Didn't Work
The power adapter itself might be dead. These are a standard 24V DC adapter. If you have a multimeter, you can check for voltage. If not, your best bet is to order a genuine Epson replacement (like part number C13T00A100) or a high-quality third-party equivalent rated for 24V and at least 2.5A.
Heads Up
Do NOT try to open the printer's main body looking for a fuse. There's no user-serviceable power component inside. All the AC-to-DC conversion happens in that external brick.