I think you mean 5volts. If so there is a test point on the circuit board on the left side of cabinet labeled 5v. Put one lead of your meter on that and the other on any black wire.
Check to see if your volume switches still work just to make sure it's only the lights.

The is a certain way you could hook something up to the light circuit and blow both bulbs. We need to check that first using a multimeter or a known good bulb.

Unplug CN6 14 pin plug at top middle of circuit board. With game on test pin #1 where red wire is. See if you get 5v there. Other lead on any ground. Check the pin on the board and not the plug.
My guess is that circuit board needs to be replaced, about $200. Unless you see the letter "F" on the board somewhere you have no fuse you can easily get to. They are sometimes in the computer chip looking things on the board but you have to replace the whole chip. Then you will need someone that knows a whole lot more than me.

You can get/test 5v off CN2, highlighted in the pic. the left most pin is ground and the right most pin is power. I would not plug that mod in again and would use a meter to test if it is shorted, which it sounds like it is. If it is a 5v mod, you can briefly test it off a 9v battery to see if it comes on.

stern coin door board (resized).JPG