I'm new to the Nitro RC game and I just picked up my first truck. It's a Traxxas Slayer 3.3 I got hole from work and am trying to charge the battery on the truck and the green led when I plug the EZ Start charger in to the wall is bright. When I plug the truck battery in it takes a couple minutes to turn red. After a while the red LED is super dim. Almost not even illuminated at all. But when I unplug it or turn the switch on the green light comes back super bright. Is it even charging? Is this a common issue? The truck is older and well used. But the wall charger is brand new right out of the box. Any help is greatly appreciated.