Thanks for contacting
. I understand how frustrating it is having trouble with your battery charger not working properly. We are here to help. Most likely the diodes inside the transformer case are bad. This is the part of the charger that plugs into the wall outlet. The black case is sealed and not designed to be opened. Since purchasing a new charger is not an option, the only way to fix it is with a new transformer. The output voltage and amperage has to match your current battery charger. Next, cut the wire off to the old transformer and strip the wire. Now, attach the stripped wire with the charger base to the new transformer. That is the only way to fix the battery charger. The replacement battery charger for the drill is no longer available. I hope this helps.
Please feel free to let me know if you need further assistance. We are always here to help.
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