The game boots with "Adjustment Error" (coin door closed) or "Factory Setting" (door open) and has lost its settings and audits.

"Factory Setting" or "Adjustment Error" at power-on

Cause: The RAM at U25 lost its memory: dead AA batteries (most often), a corroded battery holder, a bad blocking diode, or a failed U25.

Checks

• Check the batteries and the holder voltages (see the battery entries).
• Check the blocking diode D2 and the voltage at U25 pin 24.

Fix

• Fit fresh alkaline batteries, repair the holder or diode, or replace U25.
• Then clear the message from the coin door buttons.

Systems

• Williams System 11
• Williams System 11A
• Williams System 11B
• Williams System 11C

Related tips

• "Factory Setting" or "Adjustment Failure" at power-on
• Settings lost although the batteries are good (blocking diode D2)
• 'ADJUST FAILURE' every time it powers on: battery corrosion on the CPU board
• Changing the CPU batteries without losing settings
• Cleaning up battery leakage on the CPU board
• Better battery holder for System 11 CPU boards
• Fitting a remote battery holder
• A shorted D2 tries to charge the batteries

Source: Repairing Williams System 11 Pinball 1986 to 1990, Part Three, Clay Harrell