Last night I was using my vostro 1510. The battery was at 37% and I noticed the battery meter on Windows 7 wasen't rising. I hovered over it and I got a message "plugged in, not charging". I rebooted, and shutdown. I found when the computer is completely off and I plug in the A/C adaptor, the blue battery light would light up for a couple of seconds then cut off..... (So the battery was not charging when the system is completley off). I tested the adaptor by removing the battery and I could power the system with just the adaptor. I went into the bios and with the adaptor plugged in It shows "AC Adaptor type: None".
Last night I left the a/c plugged in and when I woke up the battery was not charged. I removed it and plugged it back in and it started acting normal and started to charge the battery. The BIOS even shows a 95W adaptor. I noticed it started charging the battery when the battery only had 37% life.
What does this indicate, is it normal.
Most likely you have a defective DC socket on the system board, an expensive repair. First borrow another adapter to make sure yours is OK. The DC socket has a number of small weak solder connections, which are easy to break if the DC power plug exerts much torque on the socket.
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