Reject button? I get this on occasion alsoI was getting "Coin Error" message after every flash because my coin mech was reporting as jammed. A few pushes of the reject button solved it.
I get coin error on my F3 without the multi.
I have a Supergun and if I try to use a controller that the Supergun/F3 doesn't like it will throw a coin error.
I get this on final blow as well, an older taito game.
Just adding my experience for anyone searching Taito and coin error.