Posts Tagged ‘brick’

Dell Laptop, plugged in, not charging in Vista

Monday, July 19th, 2010

My Inspiron 1525 has intermittently not been charging while plugged in. It’s gotten worse, as many intermittent problems tend to do. So, it was time for a bit of research.

It’s intermittent, so the charger generally works. I do have some battery life when it’s charged, so the charging circuits and the battery do work, though, this two year old battery doesn’t hold much power anymore.

If you search the web, it turns out to be a relatively common problem – remember, Dell sold millions of these laptops, you would expect a few problems to be reported. This laptop power connector consists of a pin in the centre of a circular connector which itself has two metal contacts, one on the inside and one on the outside of the circular ring. The inside pin is used to identify the A/C adaptor as being an authentic Dell charger. If the centre pin does not make contact with the socket on the laptop, then it will not charge; however, it will still work while plugged in.

A couple references:

– http://www.laptop-junction.com/toast/content/inside-dell-ac-power-adapter-mystery-revealed
– http://www.tomshardware.com/forum/9519-2-dell-laptop-power-jack-pinout

So, I ever so slightly bent the inside pin to the side so that it would make contact again, and it seems to be working. I’ll wonder how long it will last though.

Given how often I move my laptop around, I think it was just general wear and tear rather than a manufacturing problem. Though, I wonder if there was a legitimate purpose to the identification pin. Can an non-authentic Dell power brick really damage the battery charging circuits, while still being OK to power the laptop in “plugged in” mode?

[Edit: Hmm… upon reading some more about this, new laptops might need a way to communicate with the power brick to determine maximum power output. ¬†If the maximum output of the transformer is too low, then the laptop can skip the battery charging to keep total power consumption down. ¬†This also would be useful in “airplane” mode where there is a very limited amount of power from the outlet.]

Anyway, I’ve had a very similar problem happen with a cellphone charger a couple years back, so the fix wasn’t all that unique. Let’s hope that someday we can all have magnetic power connectors like the Apple guys…