My DSI XL will not charge or turn on.

I have a DSI XL, and have had it for a few years. It no longer powers on, or charges at all. When it is plugged in, with and without battery, I get a continuously blinking orange indicator, and when I press the power button, the blue power indicator and both screens flash for less than a second, before going black again. I have tried different batteries, and all the ribbon cables are in good condition. (I did a bottom screen replacement a while ago, but it worked for a while after that.)