I have a Dixie Narco 360 single price, 8 selection machine. About 20% of the time, the money is put in and, without any input from the user (only a couple have said they actually pushed something), the same column will vend (not the user's choice). I have replaced the motor with a new one and changed the switch with a new one. Still the same problem. Any ideas or how to troubleshoot?
you probably have a sticking selection button. If the problem is always with the same selection then either a: your replacement motor has a gummed up brake, b: your new motor switch is gummed up, or c: your selection button is sticking. If the motor and motor switch were brand new then only c: will apply. Try pressing your selection button from different angles and on different parts of the button to see if it sticks when pressed a certain way. You might need to remove it and clean dirt our around the button, replace an old button, straighten a kicked in selection panel, straighten a bent selection switch bracket, or replace a worn out selection switch spring (white plastic "sheet" part that drapes over the front of the switch. I can send you any parts for this you might need if you'll click my email link in this post.