37
REMOVE AND REPLACE COMPUTER BOARD
Tools required: ¼” and 3/8” nut driver.
1) Open the outside door to the vending machine.
2) Open the console door by depressing white latch / release button on the right side
of the console adjacent to the bill acceptor.
3) Remove the black weatherproof cover from the computer boards.
4) Note the harness positions and wiring connections on both boards, marking them
if necessary to eliminate reassembly confusion.
5) Note the 2 large brown connectors on the left side of the intermediate board and
the large white connector on the bottom of the intermediate board. Carefully
unplug all three of them, prying, gently, with a small screwdriver.
6) Loosen the two ¼” head retaining screws that hold the intermediate board bracket
onto the console. Remove the intermediate board with its bracket, leaving the
remainder of the wiring attached. Tape the board to the side of the machine and
out of your way.
7) Unplug the small two-pin connector with the twisted wire from the top left of the
computer (large) board (labeled “door”). Remove the white 6-pin connector from
the right side of the computer board (labeled “MDB”).
8) Using a
BIC
pen with the ink cartridge removed, remove the computer board from
the white mounting standoffs. Do not remove the harnesses from the board yet.
9) Install the new board onto the standoffs, positioning it the same way as the old
board.
10) Remove the harnesses from the original board, one at a time, and install them on
the new board being careful to install them in the correct positions. The blue
connectors for the keypads are identical. Be careful to position them properly,
being extra careful to center them on the plugs. They can very easily be installed
off by one pin. Each of the blue plugs has a smooth side, while the other side has
a series of small contact windows. The side with the windows always faces the
board.
11) The board has 1 jumper position on it, located 3 ¼ inches from the bottom and 3
inches from the left side (See Figure 1). If your vendor is using M-K Motors (see
Figure 1-A), the jumper should be placed over the 2 lower pins. If the vendor is
using IG Motors (see Figure 1-B), the jumper should be placed over the two top
pins.
12) Reinstall the intermediate board reconnecting the two brown connectors on the
left side of the intermediate board and the one large white connector on the
bottom right of the intermediate board.
13) Reseat all of the connectors and verify all connections.
14) Before reinstalling the board cover it is necessary to do a RAM clear. Turn all 6
dip switches to the ON position (to the left). The dipswitch block is red in color
and is located at the top center of the computer board. Turn on the power to the
computer board. The prompt will tell you to press any key. After pressing any
key the display will show the board processor checking the RAM, then the Real
