Last winter, my old HP laptop died, so I bought a used laptop on eBay: a Dell Latitude E6400. It came with a generic “replacement AC adaptor,” and it seemed to work fine. Oddly, though, I remember looking at it and seeing that it had a two-prong plug instead of a three-prong plug and thinking “I hope this is the right adaptor.” But the laptop worked, so I figured there’d be no problem.
Here’s the sequence of events that followed:
* Shortly after I got the laptop, the battery was down to 0% but would not recharge. The message on the screen was PLUGGED IN, NOT CHARGING. Wasn’t my laptop battery supposed to recharge automatically when I plugged it in?
* I did a Google (or, rather, a Bing) and found that this was a common problem for Windows 7 laptop owners. PLUGGED IN, NOT CHARGING, even with a new battery. One chatboard said that this was a “known issue” with Windows 7.
* I tried numerous solutions suggested by these people, including powering down totally and removing the battery to do a hard reset, uninstalling the battery drivers, changing the Windows power plan settings, updating the laptop’s BIOS, subscribing to a Dell update service and doing an online diagnostic… none of which worked.
* Knowing at least that the battery was drained, I replaced the battery with a new battery, which as soon as I installed it, showed that it was charged at 70% but STILL not recharging.
* Totally by accident, I discovered that someone noticed this problem when they switched out power adaptors, and that when they used their Dell adaptor (not a generic), the problem was solved.
* I ordered a used certified Dell power adaptor. As soon as I plugged it in, the message above the power icon in the tray was BATTERY CHARGING.
Problem, after eight months, solved.
Moral of the story: be careful when you buy used. Dealers like to swap out cheaper generic chargers, and they don’t always do the job, even though the specs are the same.