Got a Grand Prix that is all of a sudden always a 4 player game.
The game has been playing great lately but all of a sudden now the game goes through player 1 -4 and sticks on player 4 forever.
I have checked the player stepper unit and it is operating correctly by hand.
Must be one of the relays in the bottom that is making it never reset back to player 1 but I have no idea which one does that.
Any ideas appreciated.

Yes.

Bump for any EM gurus out there.

I will certainly check on this and report back

No. The player reset never moves because when it gets to player 4 it just stays on player 4, Ball 1 forever. Never moves back to player 1, Ball 2.

The only relay that pulls in and stays in is the Ball Index relay after the first point is scored on the playfield.

Thanks guys I will get to that after work.
All the jones plugs have been cleaned nice and shiny.
The bonus countdown steppers have been cleaned as well.
I have not messed with the player, coin or ball count steppers yet so that is probably where the problem is.
The player stepper unit in the backbox looked really clean already, so it is most likely going to be the two down in the bottom of the cab.
I will report back tonight after I get them cleaned up.
Fingers crossed.

We have a bingo.
Cleaned both steppers in the bottom and game is playing single player again.
Thanks guys.

Agreed.

The game does have one minor issue left to figure out. But it is not a big game breaker.
On the left side bonus countdown, If you only have the first light lit for 5,000 points it will not award 5,000 points if you go in the collect hole.
However if you have 10,000 points or higher, when it gets to the 5,000 point light on the countdown, it will then award the 5,000 points just fine.
Very strange.