Does your M35X, M30X, or some other Toshiba POS randomly shut off and not fully charge the battery? This is apparently a very
common problem with these notebooks. When I had to fix my girlfriend's laptop I searched all over the internet for a solution.
I found quite a few forum threads and laptop reviews discussing the issue but no one actually fixed it themselves. Lazy bastards.
Most of these folks were having them sent in for warranty work and having the entire main boards replaced. This is a ridiculous
waste of money for someone. I did see an ad for some computer repair place who was charging $200 to fix these, which is a total
rip off. They were replacing the jack (claiming $20 just for the part!!) which is not necessary (at least not with this one).
Well, I am really cheap and I didn't want to deal with the time or BS of having it shipped (the warranty is expired anyway), so
I fixed it.
Cliff's notes at bottom.
The power led on the front would flicker when the AC adapter was plugged in. I could wiggle the power cord and it would change the nature of the flickering. Sometimes it would stay on continuously and sometimes it would shut off depending on the wiggling. This behavior had the obvious side effects of shutting the computer off and never really charging the battery. Oh how irritating.
At first I thought it was the power cord. I mean I could wiggle the cord and it made changes to the flickering, so why not? After testing it with the volt meter it seemed to be good, good enough to not spend ~$85 on a new power cord. What else could it be?
The adapter jack in the machine turned out to be the culprit. Well, sort of. Technically it was the connection between the jack and the main board. Yeah, just a stupid connection. Not the whole motherboard like the corporate "customer service" reps want you to think. See, the jack has the positive connection coming out of the back and directly into the board with a little weak solder joint keeping the jack from rocking back and forth. When the laptop is subjected to normal amounts of power cord wiggling it breaks the weak joint and screws up power delivery. You can test this by plugging in the laptop and pushing the end of the cord (where it goes into the computer) in different directions while watching the green power light. Mine broke mostly on the top joint and so the light would be a solid green if I pushed the cord end UP (thereby pushing the connection back together), and would totally turn off when I pushed the cord end down.
You can view the backside of the jack by popping the little panel thats above the keyboard (it also goes over the screen hinges):
You can plug the computer in and wiggle the cord end to see if there is a visible crack. Mine had a visible crack when i pushed the cord end down. The picture above, however, was taken after I fixed it, so I have no pics of the crack.
Ok, so now you have to fix it. This is extremely easy. If you have ever soldered, you can do it. Take the laptop apart. I used this guide here which is really good. Just get the main board out so you can solder on the bottom of the jack. Once the board is out you just solder the bottom of the + terminal of the jack (the part of the jack that goes into the middle of the cord). Then solder the top. I tried to make the top solder joint as beefy as possible so it takes a while before the problem happens again. i.e. solder the circled terminal on top and the corresponding bottom terminal:
Power stuff on M35X went to shit. Wasn't the power cord. Was the + side jack connection to the main board. Take apart laptop, take out main board, re-solder on the bottom AND on the top of + connection. Put it back together. Enjoy the not-sucking laptop.