CPU board switch connectors

J206 and J207 carry the switch columns (pin 1 is column 1); J208 and J209 the rows (pin 1 is row 1). J212 goes to the coin door interface board: pins 1-3 are columns 1-3 and pins 4 and 6-8 are rows 1-4; it also closes switch 24. J205 carries the dedicated switches (coin door test buttons, slam tilt) to the coin door interface board via U15-U17. Keep J205 and J212 connected while testing.

Systems

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

Related tips

• Replacement .100" Molex parts for the CPU switch connectors
• Resets from worn power connectors between transformer, driver and CPU boards
• Switch matrix chips on the CPU board
• Testing CPU switch columns with the switch levels test
• Testing CPU switch rows with the switch levels test
• DMD shows a few dots and a coil fuse blows after reseating boards: ribbon off one row
• Several solenoids and a lamp group dead: reseat the CPU-to-driver ribbon
• Trough eject and left sling dead together: reseat the CPU to driver ribbon

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