Ihave a black and decker drill.The charger shows a flashing red light and does not charge the drill

There could be several reasons why the Black and Decker 18V battery charger's light stays red and the battery doesn't charge. Some possible causes include:

1. The battery is not properly seated in the charger. Make sure the battery is securely inserted into the charger's battery compartment.
2. The battery is damaged and cannot be charged. Try using a different battery to see if it charges properly.
3. The charger is not functioning properly. Try using a different charger to see if it charges the battery.
4. The outlet or power source you are using is not providing enough power. Try plugging the charger into a different outlet or using a power strip with surge protection.
5. The charger's fuse is blown or the charging contacts are corroded or dirty. Clean the contacts and check for a blown fuse.

If none of these solutions work, it may be best to contact Black and Decker's customer service for further assistance or to get a replacement.

My 20V battery was stored completely discharged for over 8 months. After all that time I bet the battery was holding no charge whatsoever. When you plug a completely drained battery to a charger the charger will experience a big demand in current and will fault out, flashing red. So we need to put just a little bit of charge in the battery for the charger to start working. What I did is with the battery in charger unplug and plug the charger like 10 times. Every time you plug it in it will send voltage to the battery for a split of a second before the charger fails. Eventually the battery will get enough charge for the charger to start working.

This worked for me .. Put battery in charger , unplug and plug in charger repeatedly until it charges

Did you check if the battery holds the charge? Also, you should verify the charger's output with a voltimeter.

The Ryobi charger will flash green as it charges and then remain steady or slowly flashing green when fully charged. Flashing red means testing and if it remains steady or slowly flashing red it is defective.

Either the charging adapter is faulty or the battery is worn out.

If the recharageable battery is more than 3 - 4 years old then the battery could be worn out.Rechargeable batteries have a finite number of charge and discharge cycles andwill lose their charge capacity over time, i.e. won't charge to 100% andgradually the charge reduces until the battery won't charge up at all. OR Thebattery shows a 100% charge but when the adapter is disconnected the batterydrops off to zero capacity in a very short time. If the battery drops to anunacceptable charge level then the battery needs to be replaced.

could be either one. Have you tried another battery? If not I would recommend taking BOTH in for inspection. They have a scanner that can detect if the battery has a problem. If you need to find a service center close to you go to dewaltservicenet.com and they have a locator. Let me know if you need more assistance.

Porter Cable has not offered a replacement for their poorly designed 19.2V chargers. I had the same problem and happen to like my drill and circular saw. I found a universal charger called a model number CHUN-2420. Google it--I got mine for $27 plus shipping. All you need to do to make this work is splice 3 wires.

My charger is a PC model 8624, so the instructions might vary slightly between the chargers. Remove the six screws on the bottom of your PC charger. Remove the bottom section. Remove the screw(s) that attach the circuit card to the plastic housing. Disconnect the 3 pin white charging connector from the circuit card, and cutoff the connector. Discard the circuit card and power cord. Cut the 3 conductor (red/yellow/black) cable coming out of the Chun-2420 approximately 2' from the charger. Splice these three wires to the three wires in the charger housing that connect to your battery. In my situation, Red/Red, Yellow/Yellow, White/Black. To verify, red=positive, black/white=negative, yellow=temperature sensor. Wrap the red/yellow/black cable with electrical tape where it exits the PC charger through the power cord hole. Re-attach the bottom.

If the battery gets warm after being in the charger a while and still is not charged, then the battery is bad
if the battery stays cool in the charger then the charger may be bad
Chargers usually have a light code, I.E. on means charged, slow flashing means charging, and a quick blinking means bad battery
Some chargers have 3 lights and the code should be imprinted on the charger.
hope this was helpful, cb