Hi All, Ok not sure where to from here.
My close encounters plays without issue until the game is over and it's time to remember/display the high score.
The high display score in the backboard lights but none of the displays show anything at all.
I have had the main board fully checked under load and there is no issue with it at all (New battery as well), and in fact on the test machine the high scores display worked as intended.

So thoughts on where to next?
Thanks in advance.

Thx for the prompt reply's and I will investigate these suggestions.
After reading the replies, I'm not sure if I included some details. The high scores were displaying then one day I noticed that they were not anymore. I don't believe any dip switch settings could have been changed as I have the key? But who knows. Secondly when tested by a very knowledgeable person on a Gottlieb actual test machine (Not sure what else to call it) The CPU was working fine like I have said and the High Scores were displaying on the testing equipment. It was only when I got the board back and into the machine that the same problem occurred.
Will add results after looking over the dips etc.
Cheers

Ok so I followed your advice as well as http://www.pinrepair.com/sys1/ info on clearing the audit's and am pleased to say it's sorted. Not sure why it stopped in the first place, but glad that it's now fully working. Thanks guys, your assistance is appreciated.
Now to work out how to stop credit's for high score lol and to set the machine on free play?