I have a pure av ap30800-10 to protect the home theater in my bedroom. Its 4-5 years old now. I had noticed it frequently turning off on its own and when i turned it back on it worked fine every time except the load indicator was low at 17% and the backup lights were all off. Sometimes the would all go on as they did when i first got the unit. I saw a few threads here regarding similar problems (at least in regard to the supply turning itself off) and it seemed the answer was a bad backup battery. I cant say i ever saw the replace battery light come on, but with three kids and a very time consuming job i may have missed it. The problem is, suddenly this am, it wont go on at all (its completely dead). I did open up the case and to my non electronically trained eye all looks fine. Im hoping its just the backup batteries that need to be replaced and not the whole unit as it would be aimple even for me to do that, but i would hate to wast the cash just to find out i need to replace the unit anyway. Could someone please give me aome advice? BTW this unit has been installed in the same location without any risk for damage since initial installation, and i did try all the reset turn on off unplug suggestions from other threads and still no lights/function at all. Also if the concensus is that the battery is the problem, any advice on where to purchase a replacement would be greatly appreciated.