Epson EL 486UC - Manual (Page 52)

Setting the Jumpers
If you need to change any jumper settings, follow these steps:
1. Refer to the illustration on page 3-6 to locate the jumpers.
2. If there are any option cards installed in your computer, you
need to remove them to access the jumpers. See page 3-17.
3. A jumper’s setting is determined by where the jumper is
placed on the pins. Use the following table to identify the
pin settings for 2-pin, 3-pin, and 4-pin jumpers. To identify
pin 1, look at the system board under the jumper. You will
see a triangle traced on the board at pin 1.
Installing and Removing Options 3-9