A switch shows as closed in stuck switch test 94 although it is open.

Switch reads stuck because of a shorted capacitor

Cause: Some playfield switches have a small capacitor across them, from the banded diode lug to a switch lug, and these capacitors short internally.

Checks

• In test 94, snip one leg of the switch's capacitor; if the stuck switch clears, the cap was shorted.

Fix

• Replace the capacitor or leave it off.

Systems

• Bally 6803

Related tips

• Later games check for stuck switches at power-on
• Game stays in tilt

Source: Repairing Bally 6803 Pinball Games from 1985 to 1989, Clay Harrell (pinrepair.com)