Repairing a missing display line with conductive epoxy

Steps

• Locate the broken pin (or torn ribbon) at the glass edge; it sits in line with the dark row or column.
• There is too little metal to resolder, so bond the pin back to the glass contact with silver-filled conductive epoxy.
• Keep the epoxy from bridging to the neighbouring pins.
• Expect success on one or two broken pins; more than about three rarely works. Ribbon-style displays torn from the glass can sometimes be repaired the same way, with a lower success rate.

Systems

• WPC Dot Matrix
• WPC Fliptronics
• WPC DCS
• WPC-Security (WPC-S)
• WPC-95

Related tips

• Random vertical or diagonal lines: 12 V missing at the display
• +5 V or +12 V missing at the display
• Missing rows or columns on a pin-style display
• Dot matrix display faults
• Blank display, garbage or diagonal lines: reseat ribbon cables
• Display looks cloudy on large or inverted graphics
• Outgassed displays and the 5 V supply
• Replace the whole display, not just the glass

Source: Repairing Williams/Bally WPC Pinball Games from 1990 to 1999, Part Three, Clay Harrell (pinrepair.com)