3.15.2 What to Do

1. Locate the jumpers on the main logic board.

   A main logic board jumper is identified by its jumper address, labeled on the board with the letter "J" followed by four numbers (JXXXX). Jumper pins are located immediately adjacent to the jumper address. On the board, pin 1 is marked with an asterisk.

2. Set the main logic board serial port jumpers J2604 and J2605.

   Using long-nose pliers, place a shunt over the appropriate pins according to the following table.

   Serial port jumper	A shunt on pins 1 and 2 selects	A shunt on pins 2 and 3 selects	The default shunt is on pins
   J2604	RS-232D	RS-432	2 and 3
   J2605	RS-232D	RS-432	2 and 3