Rotary Tool Battery Not Charging? Need Help!

Hey everyone, I've got a bit of a problem with my cordless rotary tool. The battery won't charge at all - I plug it in, the charger light blinks red for a second then goes off. I've tried different outlets, cleaned the contacts, but nothing. Is it the battery or the charger? Any advice?

That stinks, Chris. I had something similar happen with my drill last year. Turns out the battery was completely dead - like, it fell below the minimum voltage and the charger wouldn't recognize it. I had to use a 12V power supply to jump-start it briefly, then it charged fine. But be careful if you try that - you don't want to overcharge it. Or you could try a different battery if you have one, to test if it's the charger.

I'd recommend checking the charger's output voltage with a multimeter first. If it's not producing the rated voltage, the charger is likely faulty. Also, inspect the battery's terminals for any corrosion or bent pins - even if they look clean, sometimes there's a micro-crack. And make sure the battery isn't swollen; if it is, it's toast. Don't risk it - lithium batteries can be dangerous.

Honestly, if it's an older tool, sometimes it's cheaper to just buy a new battery. I've had that with my brand - got a replacement for $20 on sale. But if the charger is the issue, that might be more expensive. Try borrowing a charger from a friend to test. If it charges with that, you know it's the charger. If not, it's the battery. Simple as that. But don't spend too much on it - if it's old, consider upgrading to a brushless model or something.

Thanks for the suggestions. I'll try the multimeter test and see if I can find a spare battery. My tool is a few years old, so maybe it's time for a new one anyway. But I'm not ready to give up on it yet - it's my go-to for detail work. Appreciate the help!