Which fault blows which driver board fuse (WPC-89/WPC-S)

Shorted GI socket: F106 to F110. Shorted flasher socket: F111. Shorted coil: F101 to F105 and F112. +5 V shorted to ground: F113. Shorted lamp-matrix socket or caps C6/C7: F114. Failed CPU chip U20: F115. If a replacement blows at once, check that supply's bridge rectifier and regulator.

Systems

• WPC Alpha-Numeric
• WPC Dot Matrix
• WPC Fliptronics
• WPC DCS
• WPC-Security (WPC-S)

Related tips

• WPC-89/WPC-S driver board fuse ratings
• WPC power driver board fuses and what they feed
• Finding whether a blowing fuse is a board or wiring fault
• WPC: fuse holder snaps off the power driver board: replace the clips properly
• Typical causes of each blown fuse (WPC-89 and WPC-S)
• Fuse F116 keeps blowing
• Switch matrix fuse F115 (F101 on WPC-95) blows as soon as it is replaced
• F111, F112 or the line fuse keeps blowing

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