Could you tell us which Gottlieb pin this is.

Before you dig into wiring you know nothing about, please tell us which machine it is.

Congratulations, such a fun game.

Multimeter?

Ok. This is a little scary, since it sounds like this is your first machine.

The common (white) wire should go straight to the transformer. The hot (black) wire should go to the fuse block, then POSSIBLY a switch, then back to the transformer.

The fuse will protect the machine in case the transformer shorts.

The word High on the transformer refers to a tap setting. If your house power is low(very unlikely) then you move the hot wire to the high tap to get the proper voltages out of the transformer.

Keep asking questions, people here will try to help. BTW, where are you located? There may be a fellow Pinside who’s close by and can lend a hand.

Did you check the fuse? Also, with this vintage game, if the fuse is good, push the flipper buttons and see if the go (general illumination) lights come on.

Take the back off of the head and roll the credit unit to show a few games through the window on the Backglass and try to start a game.

Report back

Ok, verify high voltage going into the transformer then check the low voltage.

Let’s eliminate the cord as the problem. You should see 110vac at the common wire on the transformer and either side of the fuse block.

If the cord is good, follow the wire from the fuse block and see where it goes. Unless you have a sniffer, this will likely be hand over fist following.

Basically, you want to follow the hot wire to see where you lose power.

If it didn't come with a schematic, I'd recommend that you purchase one from pbresource.com. In this case, you probably don't need it (you can already narrow down the problem to a small number of connections), but you will in the future. I also recommend reading http://www.pinrepair.com/em/index1.htm for an overview of the parts of EM pinball and some troubleshooting ideas.

Have you checked continuity on the cord? It's possible the cord is damaged.

It's hard to tell from the photos, what is connected to the other end of the fuse? Power switch? The transformer?

I don’t think so. I think the hot wire is red with the yellow stripe connected to the tap that says normal.

Unplug the machine, and use the Multimeter's Ohm setting to trace out the 120V wiring.

Like someone else mentioned, getting a schematic would be the 1st thing I'd do.

Looks like a fun game. Its has good ratings. I am about a year into pinball myself and you found the right place for your new hobby. You will learn a bunch here. I think one of the best things I did was to read and try to understand the wiring diagram for your game. It takes practice but you'll get it. And remember,,,,, No WD40

I don’t think I can help any further without a schematic. Since you know the issue is on the coin door, I would clean the Jones plug and the slam switch contacts, then see if you can follow the power back toward the transformer. Clean the stuff with the machine unplugged since you’re searching for 115 volts.

http://pbresource.com

Order schematic.

http://pbresource.com/tools.html

Recommend order L contact adjuster (you will need eventually)

Also on that same page recommend getting new power cord if your cord is frayed and old or prongs falling out etc.

Recommend reading this:

https://pinside.com/pinball/forum/topic/replacing-line-cords-plugs-wall-sockets-vids-guide

Ditto ^^^. Hard to help w/o a schematic, and I can't seem to find one out on the net, so you will likely have to buy. I think PBResource owns the Gottlieb rights and I suspect that's why one can't be found 'out in the wild'.

If you order, might be a good time to buy a fuse kit so if you plan on keeping, you'll at least be assured the correct fuses are installed, or at least have a spare set if needed.

Goes w/o saying...make sure the 120V is isolated from the door. I don't recall when manufactures' were required to ground metal parts (like the coin door, legs, etc.). Some of the 'old timers' will likely chime in to help you sort things out. A lot of smart guys here w/a ton experience.

Gottlieb games don lit up when plugged in.
Try to start a game, then it will try to reset en lights will come on.
There are two separate hold relays: 110 V and 30 V which should get pulled in at the start.

Check the bounce off contact at the bottom and the slam switch on the door, be carefull with that one, 110 V on the door contact!

On a similar topic:

During moving an EM pin if it was stood on its end, small pieces like, coins, screws, or bits of broken plastic, can fall into switch stacks. This will cause problems. Unplugging and re-plugging in the Jones connectors can also create problems. When the pin is on a dolly and it is tilted back up with a hard hit, switch stacks can move out of position. Old solder connections can also fail, with a sudden jolt.

Hang in there, it will be easier w/a schematic.

One thing I always look for, and I saw some in your pictures...anything that looks like someone fooled around w/it. Wires that just don't seem to belong there, things taped up, odd soldering connections...all point to someone tinkering around the machine. Your HVAC experience (the electrical part) should really help you out once you can really start digging into it.

That could be the power hold relay as there are only a couple of wires running to it. By you making it close, the machine is getting power to the various circuits. Once you fix the start issue/s, that should come on automatically But if you are shorting the coin drop switch in the door, the machine will continually just keep firing away. That coin door switch should open and close the once just as if you've dropped a coin in.

Out of interest, did the score reels reset to zero as they form part of your start circuit.

I would advise you to wait until your schematic arrives, get the coin door wiring checked and rectified before you go further. The classic mistake is to try tweaking things and likely adding to your problems. One step at a time is a safe path to walk when you aren't that familiar with EMs.

Lastly, invest in a new mains power lead and run an earth wire to the coin door, and the frame that holds the lock-down bar, and flipper link rods. Oh, and check that the insulating 'fish-paper' on the coin door start switch is sound or you run the risk of a mains voltage shock. Personally, I replace it with a new one and also remove one thin spacer from the switch stack to allow for the insertion of a piece of flexible plastic to the same size of the switch blades with 2 holes drilled to go through the spacer fixing pins so that there is no possibility, once reassembled, of a shock should that fish paper ever fail. Just my preference, as my machines are on 240v mains.

Are all the score reels spinning or do some of them stop at zero?

Have you tried putting the appropriate coin in for a credit?