It's possible that a pin is not in the correct position. Take a look at the manual where it lists the connectors, pins, and wire colors and match them to the connectors in your game.

Another possibility is that you might have a shorted bridge rectifier, a problem on your power supply, or possibly the lower connector on the power supply plugged in upside down or shifted over by one pin. Do *not* plug that one in without being absolutely sure of the correct orientation, or bad things will happen.

http://www.pinwiki.com/wiki/index.php?title=Gottlieb_System_1#The_Upside_Down_A2J1_Power_Supply_Connection

Yes, that's correct.

Are those two connectors the only connectors that you repinned? Or are there others as well?

http://www.pinwiki.com/wiki/index.php?title=General#Testing_a_Bridge_Rectifier

However, if the 1/4 A fuse is the one for 69VAC, that circuit doesn't actually go through a bridge rectifier--it goes directly to the power supply.

So, Unplug the bottom connector for the power supply, put in a fuse, and see if it still blows. If it still blows, the problem may be on the transformer panel somewhere. If the fuse is fine, I'd suspect an issue with the power supply and install the new one.

When you install it, only plug in the lower connector--leave the other two unplugged for the moment. If the fuse doesn't blow, verify that the output voltages are where they should be. Then turn the game off and plug in the other two connectors and give it a try.

Ok, looks like you have additional troubleshooting to do.

On the driver board, there is likely a shorted transistor for the kickout coil that may need to be replaced. I would address that first so you don't burn up the coil.

Next, press the reset button on the MPU to clear out the memory, turn the game off, then back on again, and see what happens.

However, it looks like there is some battery damage on your MPU. That will probably prevent the MPU from working. You can either attempt to clean that up, or replace it with an aftermarket board.

Check your slam switches. They should be closed, rather than open.

From the photo, I can still see obvious signs of batter damage. Did you remove the affected components, neutralize the damage with zep, and sand down the traces to the bare copper?

Splashing a little vinegar on the affected area will not do much of anything.

Don't trust the condition of the slam and roll tilt switches. Follow online guides and jumper it on the MPU board. Fluttering displays is "almost" always a sure sign of open slam circuit.

The 4 1n4004 diodes c6-c9 on the power supply create the bridge for the 60 and 42 volts. Replace all 4 of them. 1 or more is probably bad causing the fuse to blow.

He already completely replaced the power supply.

I heard that powering up a system 1 without the displays connected can take out certain display driver chips.

Is there any self test yet? On power up do you hear a relay operate?

That's not true. You may have misheard this: disconnecting or connecting the displays while the power is on will blow chips. As a general practice, you really shouldn't connect/disconnect anything while the power is on--it's better to err on the side of caution.

Take a look at the relays and make sure the switch leafs aren't mangled--in rare cases, that can sometimes prevent movement.

Also make sure each relay actually has a spring on it and that it's properly connected.

See if you can move the relays manually and if they seem to work properly when you move them.

Perhaps a driver board issue? Check the transistors that drive the relays.

I wonder if you have a bad game PROM? A System 1 board, with NO game prom installed, will allow you to "Start" a game. At least blanking all score windows, placing a 0 in player 1, and then just sit there doing nothing else since everything else is game specific and comes from instructions in the Game PROM.

But I can't remember if it will:

Allow you to add another player (2nd push, getting a 0 in player 2 window).

and/or

It will energize the outhole coil 1 time.

I am pretty sure it will play the start up tune but that is also controlled by dipswitches and might not use the chimes if there is a dipswitch read problem too.

Of course, if you are missing +28VDC for the coils, then you won't get any reaction from the playfield or the relays.