The game boots straight into tilt and switch test shows the tilt switches (1 and 2) closed, with odd voltages on the switch matrix connectors.

System 6: game stuck in tilt with switch 1 closed: cracked pins in the 2J2 plug

Cause: The crimp pins in the 2J2 switch matrix plug had gone brittle and cracked, so some column lines lost contact.

Checks

• Measure the voltages on the 2J2 and 2J3 switch connector pins and compare them; a line that reads well below the others points at that pin or its chip.
• Pull each pin from the 2J2 housing and look for cracks before suspecting the driver board chips.

Fix

• Repin the 2J2 plug with new crimp pins (replace the housing if worn).

Systems

• Williams System 6 / 6A

Related tips

• Switch matrix connector pins and their chips
• Switch column or row fault on the driver board
• Switches stuck on: board or playfield?
• Switch matrix column test at 2J2 with Leon's code
• Logic-probe the switch matrix
• Leon test: switch column drives (2J2)
• Driver board switch matrix resistors R204-R211
• Switches missed in a System 7 game with an older driver board

Source: Pinball Repair help group!! (Facebook group)