Have a look at your outhole re circuit. A bad outhole switch or a contact of the outhole can give you the problems you have with the GP. Advice : isolate the spinner contacts when working on the GP. They try to rotate the bonus units, which are in the outhole circuit. The alternator and the bonus units are also in this circuit, so have a look at their contacts. Make sure the bonus steppers are in start position and their zero contact ok.
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