Google logo comes up, then nothing.

So with the power off, you pressed and held the power and volume down buttons and the large Android with the open door appeared. You scrolled to "Recovery mode" hit power button, screen goes blank, then Google logo displays. After a wait did the little Android with open door with "No command" text under it and nothing else not appear on the screen?

If you did then that is where you hold the Power Button down and tap the Volume Up.

The Android Recovery screen should come up. Then you can select Wipe data/factory reset.

If not have you tried disconnecting the battery? This is like a hard reset.

Have you checked inside that all connection are correct and secure?