Audits and adjustments reset when the game is switched off.

Settings lost because battery voltage at the RAM is too low

Cause: The RAM at U8 needs at least 4 V from the batteries through diodes D1 and D2 while the game is off. Below that, memory is lost.

Checks

• With the game off, measure U8 pins 26 and 28 to ground: at least 4 V is needed.
• With the game on, the same pins should read about 5 V.

Fix

• Fit fresh batteries and clean the holder contacts. If the voltage is still low, check D1 and D2 and the traces to U8.

Systems

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

Related tips

• "Factory Setting" or "Adjustment Failure" at power-on
• Battery power not reaching the RAM: diode D2
• "Factory Settings Restored" at power-on
• New batteries die in weeks or settings still lost: U8 RAM
• Cleaning up alkaline battery leakage on a CPU board
• "Factory Settings Restored" every power-on
• Changing the CPU batteries without losing settings
• Fitting a remote battery holder to a WPC CPU board

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