Quoted from RCA1:

Missing fuse appears to be the solenoid fuse. That would probably explain the lack of any action
Start by getting the instructions and manual from IPDB:
http://ipdb.org/machine.cgi?id=1778
Then try Pinwiki:
http://www.pinwiki.com/wiki/index.php?title=Williams_System_3_-_7#System_7
Sounds like either a shorted coil or a wire shorted somewhere is blowing the fuse.
Good luck!

Quoted from dozer1:

Welcome to Pinside! Good luck on tracing down the short that is likely taking out that fuse. Make sure to only use the properly rated fuse and to not try higher ampere fuses. RCA1 set you up with the links to download the manuals which will be needed if you haven't already done so.
If you can locate a pinsider in your area or know anybody that has been into this hobby for awhile, it can be very helpful to just have someone help you out a little bit at first. I was lucky to have a helpful pinsider work with me on some of my early Gorgar problems. That help went a long way into getting me started on doing my own diagnostics and repair. Best of luck to you and please update with your findings.

Quoted from GRUMPY:

This is for all the coils in the game, one or more could be bad causing the fuse to burn. Check each coil plunger for smooth easy movement, brown or burn coil wrappers. If you find a bad coil, cut one of the wires off and insulate the wire then try a new fuse and see if it blows again.

Since you have no battery connected to the board it's losing it's memory stored in the ram when the power is shut off. When you turn it on it can't find the stored info so it gives you this fault.

Vid1900 has has a bullet proofing guide on pinsides that is very informative.

Quoted from Axl:

I have a pharaoh that had some minor problems. One thing I did was to change the fuse holders under the play field to new ones. They are near the flippers.
Also, remember that you have to have both balls in the through when you boot up the game. That caused me a lot of head scratching.
Congrats on a great game!
Axl

Quoted from Axl:

I have a pharaoh that had some minor problems. One thing I did was to change the fuse holders under the play field to new ones. They are near the flippers.
Also, remember that you have to have both balls in the through when you boot up the game. That caused me a lot of head scratching.
Congrats on a great game!
Axl

Quoted from Axl:

I have a pharaoh that had some minor problems. One thing I did was to change the fuse holders under the play field to new ones. They are near the flippers.
Also, remember that you have to have both balls in the through when you boot up the game. That caused me a lot of head scratching.
Congrats on a great game!
Axl