He uses it exclusively in credit mode. Registers wins, but won’t pay any of the small wins.
not sure what you mean:
1] it pays 14+ pays, but not 2/5/10 pays
2] the payout relay powers on the 2/5/10 pays, but no credits are added ... which wouldn't make much sense.
if [1], the 2 pay is an oddball since it goes thru an "open at 20" carriage switch ... the vertical switches on corner of the trace side of the payout counter. The 5 and 10 pays are just the usual path thru the reel wipers to the 5/10 traces.
often the issue is poor wiper<->trace contact due to dirty traces on the payout counter. If it's not that, then problems with the plug connections or reel wipers is all that's left since the remaining circuitry is common with the higher pays that work.
the low pay wins - oranges and cherries - are detected when the reel wipers are held far away from the reels. Make sure the reel shaft is locked into the notches correctly and check the reel wiper contact alignment when cherries are on the payline.