I hope this is the right place for this question. I have an LG R310 laptop. Recently the adapter connector started playing up, so I got a second hand replacement adapter of the same rating. The adapter was a cheap type (I know I made a mistake) and faulty.. it made a low buzzing sound when plugged in and not connected to the laptop. It didn't make the noise when connected to the laptop. Foolishly I used this adapter for several weeks.

One day the adapter stopped working. The led didnt work and it was not charging. It had also drained the laptop's battery to 0%. I then got an original replacement adapter. Now I can use the laptop on power but the battery does not charge. The charging light does not come on. The interesting thing is that when I remove the battery the charging light comes on and stays on after I insert the battery back (the battery still does not charge).

I need to know if the faulty adapter damaged the motherboard or if its just a problem with the battery. I have a multimeter and I prefer not to open the laptop.

Thanks in advance.