We have two Bally reel slot machines (Crazy Joker and California Dreamin) and both have error code 54 (drop door open) but we can't figure out where the drop door is? Can anyone help?

Bally considers the bill validator door a drop door, on the side of the machine where you pull the can out. http://slotrepair.blogspot.com/

Any door that opens has a switch that will cause a drop door error.

Thanks for the info. We'll check around the machine.

are these bally 5500 or 6000