38
Cause
Corrective Action
damage.
Problem 2: Blank LCD
Cause
Corrective Action
Connection
problem
•
Ensure LCD large Flat Ribbon Cable adequately connects the main board with the
display at the main board end.
•
Ensure that the cable has been inserted adequately into its socket on the main board.
This is a Keyed connector with locking arms. The arms should point to the same
direction as the cable. See Figure 2-1 below.
•
If the LCD Display is not on, check power to main board as detailed in Problem 1.
Contrast problem
•
Adjust the potentiometer on main board by rotating the top metal part using flat
screw driver to achieve the best LCD contrast. Rotating the part in the counter
clockwise direction will increase the contrast. See Figure 2-2.
•
If the LCD remains blank, replace it.
Defective LCD
•
Connect a new LCD to the LCD port on main board.
•
If the new LCD functions properly, this indicates the old one is defective.
•
If the new LCD does not work, replace the large Flat Ribbon Cable.
•
If the LCD still does not work replace, the main board.
Problem 3: Inoperative buttons
Cause
Corrective Action
Connection
problem
•
Does the LCD display work? If it does not, please refer to Problem 1 and ensure that
the main board is powered.
•
Ensure that the small Flat Ribbon Cable is connected to the main board – See figure
3-1. The triangle sign on the female connector of the cable indicates PIN number 1.
•
Interface board and membrane/keypad are located behind the blue panel,
underneath the metal light deflector.
•
Turn off the cabinet and then remove the bulbs and the clips that hold the bulbs. See
Figure 3-2.
•
Ensure adequate connections between the cable from the main board and the
Interface board. See Figure 3-3.
•
Ensure adequate connections between the green plastic cable from the Interface
Figure 2-1
Figure 2-2
Summary of Contents for Class II
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