Hello,
I am deploying a bunch of arduino Unos throughout my place, all with the same program and same setup. They are all powered by a 12V battery, and they all work fine, except for one. I have the debug LED blink every loop, and this one just flashes waaaay faster than the rest. My switches and other components I have hooked up to it don't work. That is until I plug in the USB to the laptop. As soon as I do this, the blinking speed is normal, all my components work etc. As soon as I unplug it, everything goes back to malfunctioning. The battery is full, no shorts or loose wires, I can't think of anything else.
If I am missing something I would appreciate any help. Thank you!
EDIT: I forgot to mention a lot of the previous posts have mentioned a voltage regulator, but I have Xbees hooked up to all of them, and I can talk to it just fine, so it is powered fine.