I was charging up my battery on my 149 tonight because it has been sitting for a while in a non-heated garage. At first, when I touched the connectors to the terminals I got the usually light sparks. I tried to start it some time later and it didn't fire up. Then, I went back to check my connections to the terminals and despite my many hook-ups and re-hood-ups, there was no sparks when I touched the connectors to the terminals. Any idea what this might be?

Thanks in advance for entertaining my question!!
With much appreciation,
Cub Cadet 123