When my RFM was blowing a fuse, it would seem to happen right upon start up of the machine. I checked for shorts, and then sent the board out. I just looked for the email where they told me what they replaced on the board but unfortunately I can't find it. They fixed the problem though.

Whichever fuse I was blowing was affected half of the computer controlled lamps. The game still seemed to play fine. But it was so nice to get it back to normal. Sorry I don't have more helpful and specific info for you though :/

Replace the fuse, pull connectors J101 and J102 from the power driver board and then turn on the machine. If the fuse doesn't blow, the problem is a short at one of the flashers on the playfield.

If it does blow, the problem is on your board. I'd look at tracking down what is probably a bad diode at D41, D42, D43 or D44 and replace as necessary. If you can't do the work, contact Borygard/Rob Anthony at http://www.lockwhenlit.com. He's the known P2K guru!

All the lamps will show bad after replacing them with Leds on pin 2000. Leds dont draw enough current so the cpu thinks they are out.

If you just replaced them and a fuse is blowing check under your playfield that no lamp wires are touching coils or switches. Maybe you bent a socket back to put in a bulb and its hitting a coil or flasher wire. Also possible that a flasher socket is shorted.

Also that no wires from coils or switches or lamps broke off and are touching something they shouldnt.
Common after moving things/wires around to change lamps. Specially if it was fine before.