New coil just arrived today. So I put it together and hook it up to charger for initial charge. The charging light won't stay on when it charging. It might stay on for 30 -40 seconds the it will start to blink a few times like it's fully charged. Then the light will stay on again for a while, back and forth. Wondering what the problem is, I've reconnected the charging clamp several times. Now I'm wondering if it's really charging or not. Never had this happen to my x-35 coil. Any ideas about what's going on. Thanks