WPC direct (grounded) switches

Grounded switches are outside the matrix and pull an input straight to ground. On WPC they are the coin door switches (except slam, which is in the matrix) wired to the CPU board, and on Fliptronic games the flipper buttons and end-of-stroke switches wired to the flipper board.

Systems

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

Related tips

• WPC flags a bad switch at power-on
• WPC switch matrix basics
• Switch matrix wire colors (all WPC games)
• Reading WPC switch numbers and the switch test display
• WPC switch numbers give the column and row
• Using the switch edge test
• Check playfield switches with the switch edges test
• How the switch matrix reads a switch

Source: Pinball Machines: How They Work & Troubleshooting, Norbert Snicer