Deep breath. Check out the transistor that controls your flipper relay. It's Q80, a small one, to the left of the relay box. Had those go bad on me several times. Next time, try to post a little more informatively. At least let us know which board you switched out.

Okay, can you start a game with the head open, and see if the flipper relay is working? You can usually hear a click, but a visual is best.

Okay. So we gotta trace backwards. Do you have a multimeter or a logic tester? We need to see if that transistor is getting a signal or not.

Alright. Well, you want to put the black lead on a ground, and probe with the red lead. If your meter isn't auto-ranging, and it probably isn't, you want to twist the knob so that it points at the dingle digit DC voltage setting. If you can't figure out what that is, post a picture of your meter. You're going to be touching the board while it's on, with the red probe. Anywhere you find 4+ volts is "high", anywhere you find below 1 volt is low. If it's inbetween the two, it's floating, and that's no good usually. So to start out, measure and see what voltages you have on each of the three legs of the little transistor you put in. You should do this while the game is on, having started a game. Try not to short the legs together with your probe, although in this case it's not the end of the world if you do.

Um, what's floating? There are three legs to the transistor. Are they all floating?