The game plays normally with no errors, but coin switches only make a sound and never add a credit.

Motordome plays but won't add credits: corrupted settings, do a factory reset

Cause: A dead backup battery let the stored settings become corrupted, leaving the pricing at an invalid value.

Checks

• Check the backup battery and the pricing settings with the keypad.

Fix

• Do a factory reset with the keypad, then set pricing again (or set free play).
• Replace the NiCad battery with a remote battery holder or NVRAM so it can't leak on the board; settings must be re-entered after the change.

Systems

• Bally 6803

Games

• Motordome

Related tips

• Factory CPU jumpers by game

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