DSI flashing light, turns off when attempted to turn on
So I recently bought a new touchscreen and shoulder Button cable for my DSI and I didn't get to test them cause it wouldnt turn on. I figured I put the battery in backwards and I checked the fuses and the fuse on the button board seemed to be dead. So I ordered a replacement that just came. I installed it, the fuse looked good, and it still did the same thing. I have two batteries and they don't seem dead as the multimeter says one has ~3.8v and one has ~4.1 volts. I put it in a bunch for both, tried many things, took out and reattached screen and camera cords, and nothing seems to work. I need help with this please!!!
Is this a good question?