Hi Pinsiders. After cleaning my Space Mission I have the following problem:

1- Machine is turned on and Game Over is indicated with previous game info.

2- Press credit button and machine resets scores and ball count but instead of One player it always go to Two players. After that, machine plays well all balls for two players (or three or four if pressing credit button two or three times) and game over.

I suspect the problem is with Coin Unit so I cleaned, reassembled and adjusted it to no avail. I should mention that very seldom when pressing credit button powering on, the machine does go to one player.

Any suggestions appreciated.

Hi and thank you HowardR. The reset and step-up solenoids work well. If manually press the reset solenoid, the geared wheel goes all the way back to One player. When the reset is activated by the credit button, though, I can see that the wheel goes all the way back to One player but instantly steps up to two players.

I tried different tensions on the spring that moves back the wheel; cleaned the whole unit; changed various positions for the contacts that are pressed by the pin on the wheel but without success.

Thanks currieddog. I removed the wheel, cleaned and re-installed. The wheel it's attached to its axle with a rectangular slot that doesn't permit altering its position. Furthermore, when resetting manually it goes back to One player.

Let me clarify what's happening. When I press the Credit button one time after turning on the pin, the Coin unit resets to One player and right immediately moves to Two players. This action is almost instantaneous i.e. like rebounding. If I do the resetting manually it stays in One player.
Somehow when pressing the Credit button the resetting ads one credit.

Problem Solved! As indicated by HowardR, Coin Relay contacts were not contacting properly. I reviewed contacts, aligned them and voila!

Thank you HowardR for your time and help. I put this thread now to rest.