I helped my in laws build a small front deck yesterday. Charged up my batteries the day before at home just fine. After about a hundred 2 1/2" deck screws my impact driver (BTD140) started to sound a bit unusual but nothing too weird. It also got pretty hot and seemed to be loosing power and driving screws less efficiently. I stopped using it and used my drill/driver which finished the job doing another 500 or so screws on my last two batteries (I have 3 total).
Toward the end of the project, I put a dead battery in my charger (DC18SC) in case I needed it. My charger's fan sounded louder than usual but it's done that before.
There were a couple light rains during the project but nothing soaking and I covered the charger.
So, I get home and check the brushes in the impact and they look fine, check the switch for obvious signs of overheating and it all looks good. There was never an issue of the trigger not working properly. I blew out the dust and crossed my fingers.
The charger reads that ALL three batteries are defective. I find that nearly impossible that all three died simultaneously. I understand there's a max # of charge cycles before the battery's computer seems it dead.
These tools are about 10 years old I think, have been only been used in my hobbiest woodworking shop, around the house projects, and DIY car work, and have worked great.
Any suggestions on the charger or the impact? New chargers seem to sell on eBay for under $40, should I try a new charger?