Battery not charging on my circular saw - help!

Hey everyone,

So I've got a DeWalt 20V circular saw (DCS391) that I've had for about 2 years. The battery (5Ah) suddenly stopped charging. When I put it on the charger, the light blinks red instead of solid green. I've tried another battery and it charges fine, so it's definitely the battery.

I'm pretty meticulous about my tools, clean them after every use, store them in a climate-controlled shop. This is driving me nuts. Any ideas? Is the battery toast? I really don't want to drop $80 on a new one if it's something simple.

Thanks in advance!

Tim, red blinking light usually means the battery is too hot or too cold, or there's a cell imbalance. Since you said it's been stored in a climate-controlled shop, probably not temp. Could be a bad cell. Two years is about average for those 5Ah packs if you use them hard.

Have you tried discharging it completely then recharging? Sometimes that resets the BMS. But honestly, if it's blinking red and other batteries work, it's likely a dead cell. You could try to warranty it if it's within 3 years. DeWalt has a 3-year warranty on batteries. Check your receipt.

Good luck!

I had the same issue with a Ryobi battery once. What worked for me was the 'jump start' trick with a good battery and some jumper wires. But that's risky and can cause a fire. I wouldn't recommend unless you're desperate.

Honestly, just buy a new one. Check Amazon or eBay for deals. Sometimes you can get a 2-pack for cheaper. Also, consider switching to a different brand? I've had good luck with Makita batteries lasting longer. But that's a bigger investment.

BTW, welcome to the forum! Lots of good folks here.

Thanks Wendy and Will. I was afraid you'd say that. I checked the warranty and I'm about 2 months past the 3-year mark. Figures.

I'll try the full discharge/recharge cycle first, but if that doesn't work, I'll just bite the bullet and get a new one. I'll look for a 2-pack deal.

Appreciate the help!

No problem, Tim. Let us know how it goes. And hey, if you do decide to crack it open to check the cells, be careful. Those things can hold a charge and bite you. Wear safety glasses.

Also, don't toss the old battery in the regular trash. Take it to a recycling center or Home Depot. They have bins for that.