The game reports a G10 error and the serial number at boot shows as all zeros.

G10 error with serial number all zeros

Cause: Often the 74HC574 data handling chip at U24 on the CPU board, rather than the PIC.

Checks

• Check the PIC is the correct one for the game.

Fix

• Replace U24 (74HC574).

Systems

• WPC-Security (WPC-S)
• WPC-95

Related tips

• "U6 Checksum Error"
• "Checksum Error" at power-on
• Why coils stay off until the CPU boots
• Signals a dead CPU board should show
• "Time and Date Not Set" message
• Dead CPU: no clock signal at the 6809
• Dead CPU: check the reset and IRQ lines
• CPU won't boot, blanking LED stays on: check the game ROM

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