My orbital sander battery won't charge - help!

Hey guys, I've got a problem with my cordless orbital sander. The battery won't charge at all. I plug it in, the charger light flashes red, and it just sits there. Battery is only about a year old. Any ideas? I've tried cleaning the contacts and stuff.

Could be the battery itself is dead. Sometimes they just die after a year, especially if you leave them in a hot garage like I do. Have you tried another battery or checking the voltage with a multimeter? If it's reading low, it might be toast. But if it's a name brand, maybe warranty?

Before you go buying a new battery, let's talk safety. The flashing red light on the charger usually indicates a fault. Could be a short in the battery or the charger is detecting a bad cell. Make sure you're not charging it on a flammable surface, and check for any swelling on the battery case. If it's swollen, dispose of it properly - don't just throw it in the trash. Also, check the charger itself for any damage. I've seen chargers fry batteries before.

Thanks for the replies. I checked the voltage with a multimeter and it's reading 10.8V on a 12V battery, so it's not completely dead. But the charger still flashes red. I haven't noticed any swelling. Maybe the charger is the problem? I'll try borrowing a charger from a buddy to test.

Good thinking. If the voltage is that low, it might be below the charger's threshold to start charging. Some chargers won't charge a battery if it's too low, to protect the cells. You might need to 'jump start' it by briefly connecting it to a good battery in parallel or something. But be careful - I saw a video on that. Otherwise, a new charger might be cheaper than a new battery. Let us know how it goes.