The game shows "Factory Settings Restored" at power-on and has lost its settings and audits.

"Factory Settings Restored" at power-on

Cause: The CPU RAM at U8 lost its memory, usually because the three AA batteries fell below about 4 V. Next most likely: corroded battery holder, bad blocking diode D2, or a bad U8 RAM.

Checks

• Measure the battery pack: about 4.5 to 4.8 V.
• Measure U8 pin 28 with the game off: at least 4 V.
• Check the holder and diode D2 (see the battery entries).

Fix

• Fit fresh alkaline batteries (yearly).
• Replace a corroded holder, or fit a remote holder.
• Replace D2 or U8 if they fail their checks.

Leaking batteries are corrosive; wear gloves when removing a leaked battery and clean the board right away.

Systems

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

Related tips

• "Factory Settings Restored" every power-on
• "Factory Setting" or "Adjustment Failure" at power-on
• New batteries but still losing settings: test the holder
• Battery power not reaching the RAM: diode D2
• New batteries die in weeks or settings still lost: U8 RAM
• Settings lost because battery voltage at the RAM is too low
• Factory settings restored at every power-up after new batteries: do a factory reset
• The batteries also power the U9 ASIC clock

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