Quoted from Graysonsdad:
For what it's worth, I played all last night with the board out and.didnt notice a difference. I'll be putting it back in incase it is to do with burning coils but it's an odd thing, that's for sure.
The LED on it, does it ever light up or blink to begin with? Like when game is on, during play, during diagnostics or when activating the coin switches, see if it ever comes on or blinks or flashes. The thread about the one in Firepower doesn't mention if the LED comes on or not either. Course it's always possible the board itself has failed and why you don't see any difference with it in or out, whatever the hell it's supposed to be for.
Is it possible it's related to how a game can't start if the cpu doesn't see all three balls sitting in the trough(s) so this thing somehow bypasses that in case of dirty switch(es)? Board age is only 2 years older than BK and Firepower and that switch thing would kill earnings, those are notorious for being glitchy even after they have been cleaned. Firepower, same thing where it has to see all three balls, and it was their first solid state multiball. Goofy idea, all I can think of.