Original post by: paul78zephyr ,
We had the same exact problem with the right D-pad (cross) button and it was - temporarily - repaired with a replacement power supply board (which had the D-pad buttons on it). However a few weeks later my son said the unit would not power up and the charge indicator light was flashing. I opened the unit again and found that the two tiny red and black wires that go from the PS board to the motherboard had been 'pinched' between the case halves and damaged when I installed the new PS board (I can see conductors thru the insulation where it was pinched). These wires route thru a tiny slot to hold them in place and away from the case halves but I did not realize that at the time. Also upon close examination of the new board and the original board I have found that those tiny wires are longer on the new board and therefore their routing is even more critical as the 'excess' wire is very prone to be pinched if not routed just so. The bottom line for us is that the damaged wires must have shorted because I discovered that the tiny 'F1' SMT fuse on the new PS board is blown and that I cannot repair. I have verified that this is the root cause as I have re-installed the original PS board (with its bad right D-pad switch) and other than that the unit works normally. I have ordered another PS board at this point. So if you replace your PS board due to a bad D-pad switch (or other reason) be VERY careful when you route the red/black wires between the PS board and the motherboard so that they do not become damaged.