Haywire S+ ?

[61Wally]

Happy independence day to All. On this machine it has a WBA Validator. When playing the machine, I have to push “CASH/CREDIT” button to accumulate credits. When I insert currency into the Validator, and it starts thinking about accepting the bill, The “CASH/CREDIT”, “MAX BET” and the “INSERT COIN” lights flicker. Once the bill is rejected, the lights go back to normal. The “BET ONE” light is NOT affected at All.
I have swapped out validator, cash can, power supply for validator, and reseated All the connections to the back plane. The equipment works in other S+ machines fine. I thought, maybe losing a ground with the flickering, but the “BET ONE CREDIT” light is Not affected, Possibly on a different circuit? Any thoughts/ suggestions on this weird scenario?
THANK YOU, TAKE CARE.

[knagl]

On some SP chips, the Insert Coin lamp will flash if a bill is inserted and the validator is using the wrong protocol. Ensure that the protocol on your WBA validator matches the protocol called for by the SP chip in your machine.