well that makes all the difference in the world
yes most newer chargers are called 'smart chargers' and should not start up unless it see's a certain voltage before it starts.
The only problem with some forklifts is some of the components do store voltage in their capacitor circuits and they sometimes feeds back through the battery circuit... this would be why the charger may have kicked in just long enough to blow the card or damage it to the point that it self destructed when trying to run the truck.
Schaeff trucks had this problem until schaeff figured that out and put a circuit in place to prevent that... those control card dash displays for those things were very expensive :o)