\nThe following is by my understanding.<\/p>\n
\nMy wife got me a drill\/impact wrench set from Milwaukee tools maybe a year ago. It revolutionized my handyman chores.\n<\/p>\n
\nI recall having to charge the cells before using the drill and the impact drill. When I slid one cell into the charger, the indicator went solid red, which means it’s charging. You want that.<\/p>\n
\nThen, when charging is finished, the indicator light on the charger turns solid green: you want that, too.<\/p>\n
\nSuch happened with the first cell. However, with the second, the indicator light flashed red\/green when I slid it in. You don’t want that; the manual seems to suggest that it means either the contact isn’t good, or there’s a hardware problem either with the cell, the charger, or both.<\/p>\n
\nSince the set was brand new, I didn’t want to think it was already defective. I played around a bit, slightly changing its geometry in the charger. After a couple of minutes of this, the indicator turned solid red: charging. I wanted that.<\/p>\n
\nHolding the cell in place in the charger, and my breath, I continued to watch the indicator light, wondering if it would start to flash. It did once, but by readjusting the position of the cell I was able to bring it back to solid red. Eventually, I could let go, and the indicator remained solid red. A few minutes later, I checked back: solid green. I wanted that:)<\/p>\n
\nCharging time doesn’t seem very long, anyway. I didn’t time it, but it seems maybe it took half an hour(?) from near-dead to full charge. That’s a very loose guess.<\/p>\n
\nBest of luck:)<\/p>\n