It is getting a cycle signal from somewhere. Could be....
1. broken cushion start switch or missing spring, shorted wires
2. ball detect
3. shorted reset button wiring at ball return or bad wiring in the subway
4. rear control panel cycle button wires have short or bad button
5. If AMF scoring, problem with MIU
6. short with "10th frame switch" wires in A&MC box
7. I have also had this happen with a solid state chassis on the C2 plug, one of the cushion start swirch wires was shorting to a ground wire
8. if any added cycle buttons, check for shorts/grounds, etc..
Simple and obvious things first.... start with the cushion start switch then go from there.
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