The manual/schematics is the best place to start

Other resources are Clay's guides (posted on various pirate sites) and pinwiki. And of course, just ask specific questions here.

As for your left slingshot lights they would be GI (general illumination). They have a constant 6.3VAC voltage and are wired in parallel with all other GIs on that same circuit. So, if you only have a few sockets out on a GI string, then you've likely lost the voltage wire(s) that go from one bulb to the next. Use a meter and start checking each bulb socket to see where you've lost voltage. Follow the wires. If the entire string is out (here's where the manual comes in handy), then you've got a blown fuse or bad connector on the board.

http://www.thepirates.net.au/arcade/Pinball/PinRepair/Apr-11/Pinrepair/Pinrepair.com%20Repair%20Manuals%20Apr%202011/Williams%20Sys%203-7/

System 6 guides.

I used to work in tech support and always had people try the dumb things first like:

1. Is the computer plugged in?
2. Can you try something else you know works there?

You'd be surprised how often stuff like that fixes things hardware wise.

I carry that over to fixing pinball. The first thing I do is try a known good bulb there. If that doesn't work, then trace it back. Can you disconnect the entire string and measure to see if it's getting power? It's not? Then trace it back one further to the motherboard, and see if it's getting power to those pins there, and on and on.

In tech support reseatting boards really does solve a lot of issues, and I've found that doing the same on pinball boards. Taking off the connectors and just reseating them can solve issues.

Lastly my other dumb test, is to looks at the parts themselves, either on the board or otherwise. Is there a duplicate somewhere else? Do they look exactly the same finish wise? If they do, then they are probably good. If they do not and one looks a little rough or has some char on it, it's probably been blown and should be investigated further.

Oh, and google is your friend, search the problem.

That's it, those are my dumb solutions first. After this, I go to the manual!

It becomes easier the more you repair games. I've been at this for 10+ years now, and it seems I learn a little more every time I tackle a repair. A schematic that once looked like Greek to me now has a lot of clarity. It's no longer a big piece of paper with multiple lines on it!

We all start somewhere. I've always been a tinkerer. I used to be nervous about taking one flipper apart and getting it back together correctly, now I scatter an entire game into a pile of parts, and don't take many notes in the process, then rebuild it from the ground up.

I don't know how your 'brain works' - that's not an insult, different people think about things in different ways. Looking at the bulbs under the slings, for example - I know those bulbs are GI. I'd check at the socket for approx 6.3 VAC, the traditional voltage for GI. If that's missing, there's the problem. If the voltage is there, and the bulbs are out, it's most likely the bulbs.

If the 6.3 VAC is missing, I know from history that GI is often burnt connectors. I also know that GI bulbs are in 'strings' - multiple balls fed from 1 power source. If the other GI bulbs are good, I'd find the wires leading to those sockets, and trace the wires back to where they are fed from - just trace the wires back to a previous solder point, and see if maybe there's a broken wire.

Deductive reasoning is your friend. You learn to deduce better the more you work on pins

Asking questions is fine. It's great, actually. Never be afraid to ask for help

That is a good point and I always snicker when I lift a pf and people gasp and cry out "holy crap" as they look at all of the parts and pieces. With that being said we all started some where and you won't learn unless you try.

As for your GI, sometimes those sockets can go bad so you can check for the voltage (as stated above) and you can also use a jumper wire from the tab of a socket with a working bulb to the socket tab of the one in question. Its just a dirty test I use to narrow down the problem of nonworking lights, ruling out the bulb, socket and grounding. Good luck and don't ever feel worried about asking questions here.

just about everything you need to know is all right here!!

http://www.pinwiki.com/wiki/index.php?title=Williams_System_3_-_7

Use your common sense and don't over think things.

And some basics in electronics. Which with Google or YouTube you can learn. Get a battery, some wire and a light bulb, make a simple circuit, see how it works.

Get a meter, practice on your table or work bench. Take readings of your battery, get some resistors, transistors, diodes, practice measuring them.

Then apply these basics to your game.

GI bulbs not working, what makes them work. Hmmmmm. power. Grab your meter, set to AC, see if power at the sockets yes/no ? Then you know which direction to go next. Yes forward, no backwards.

Apply the same thing to your game. Coil doesn't work ? Work in test or game play ? What makes it work. Same thing for a switch.

And if you are working on your game, and now it does something bad. What did you work on ? Go over your work first.

For the average pinball problem, you couldn't ask for a more simpler thing to work on. And often in tests, the game itself will help you.

And as you gain in knowledge and experience, you'll be quicker to diagnose and repair.

LTG

I have found that it is usually simple. A loose wire or a dirty connection. I always start there. There are times when it is a chip, but that seems to be more rare.

I disagree, fewer pins to go around

First download the manuals I linked for you up top. Those are the bible.