Charger Problem

Hi, i'm having a problem with the charger on my bit. It worked initially but now it wont.

When I clip the car onto the remote, the light comes on for a fraction of a second then goes off. The car definately doesn't charge after the light goes off. If I quickly put the car on and off over and over again the car will charge a little.

I have tried brand new batteries checked the connections to the charger and checked the battery in the car. Anyone got any ideas what might cause this?

Thanks in advance

Chris