>>38524369Battery is dry and needs to be replaced. Very easy to do, and you technically don't need a soldering gun to do it.
If you just want it to work, open the cartridge (it's easy if you have the right tool for unscrewing the back, if not, a skinny pair of needle nose pliers might work). Then, take out the chip inside and pry the battery off the metal contacts (a flat head screwdriver makes this pretty easy). Then, put a new battery in and tape the contacts around it. Put it all back together and it should last another several years before needing to be replaced.
