take a multimeter and set it to volts at a suitable scale. Check if you have a voltage across the terminals of the pack. If you don't then open up the pack and have a look at the connections and cells. If any appear different from the others (broken, burst etc) then you could feasibly repair the pack depending on what's wrong.

Matt you would be better flogging those on ebay. As mentioned elsewhere, everyone has drill packs coming out the wazzoo usually so they will fetch little if anything here.