Reseating the U9 ASIC on a dead CPU board

Steps

• Use a proper PLCC extraction tool; never pry the chip out with anything else.
• Remove and refit the ASIC. Its angled corner notch must match the socket's.
• Press it in until it snaps home, checking it is square so the chip and socket aren't damaged.
• If that doesn't help, check socket continuity with the chip fitted before replacing the 84-pin socket.

Systems

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

Related tips

• Dead CPU: isolate it from the other boards
• Dead CPU: the order to replace chips
• Signals a dead CPU board should show
• Dead CPU: checking address and data lines
• Dead CPU: no clock signal at the 6809
• What is on the WPC CPU board
• CPU board completely dead
• Which System 11 CPU boards fit which games

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