Black & Decker Drills - Page 8 - Recent Questions, Troubleshooting & Support

You should have been supplied a "chuck key" which you engage and rotate the barrel of the chuck which releases the drill bits or tightens them. If you did not get the key (it looks like a bevel gear with a "T" handle) you will need to get one.

9 times out of 10 problems like this are the result of a bad battery, in other cases it can be a bad charger. Without knowing more information I cannot give you an exact diagnosis. This is the first question I ask when approached with this issue, Has this drill been sitting for a period of time and if so, was the battery charged before it was put away? If Yes, the drill has been sitting and No, it was not charged are your answers than chances are your batteries are dead. This tool has Ni-Cd batteries that self discharge as they sit, eventually these batteries discharge until they have nothing left. In addition, if the battery is stored in a cold garage/shed will speed up this self discharge. I always tell people to think of their power tool batteries just lie a just like a car battery that dies if it sits too long without being started.
If you do not use your power tools on a regular basis it is recommended to fully charge the batteries before storing them or else they will self discharge until completely dead. Another option is the newer Lithium-Ion power tools batteries are not as temperature sensitive, have a much slower self discharge and can sit for 12-18 months before starting to loose their charge.
A replacement battery for this drill runs about $42 plus s/h and can be purchased directly from Black & Decker (1-800-4-DeWalt or www.dewaltservicenet.com) My recommendation is to purchase a new drill. For around $40 - $50 you can buy a newer upgraded model with new battery and charger.
If you think your issue may be something else, please feel free to ask. If you feel I have helped explain or resolve your issue than please rate me. Thank you

Possibly he brushes are gummed up / jammed - hence not making contact with armature.Remove and cleann brushes and brush holders.