The game powers up with GI and attract lights, but the credit/match display stays blank, the player displays flick between zeros and fives, there's only speaker crackle, and a game can't be started. It failed after being left on for hours.

Credit display blank and game won't start: reseat the EPROMs

Cause: Poor contact in the EPROM sockets on the CPU board.

Checks

• Confirm the credit display itself works (it did in another game).
• With power off, check the EPROMs are fully seated and the socket pins clean.

Fix

• Reseat all the EPROMs firmly in their sockets.

Systems

• Bally 6803

Games

• Eight Ball Champ

Related tips

• Factory CPU jumpers by game
• Reseating socketed chips
• Test EPROM fitted but the LED does not blink

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