Using the switch edge test

Steps

• Press Begin Test and note any test report.
• Go to the Test menu and choose T.1 switch edge.
• Roll a ball over or press each switch; it should appear on the display with its wire colors.

Systems

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

Related tips

• How the switch matrix reads a switch
• Switch 24, the always-closed switch
• How the Williams switch matrix is scanned
• How the always-closed switch 24 is wired
• WPC switch matrix basics
• Switch matrix chips on the CPU board
• After a new U20, work every flagged switch once
• One switch does not work

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