AC Adaptor Plugged in No lights. toshiba p300-134

@aftaster if your AC adapter does not seem to work, your battery may just be to discharged to have any impact. For now you would need to check things out.

Start off with the simple things. First you want to check your power supply. Make sure it has the proper voltages (19V). Check to make sure connectors are not bend etc. After that, check the charging port. Clean it of any debris etc, use a few puffs of air to clean it out. Check the DC-in jack of your laptop. Make sure there is no corrosion, debris etc. that prevents it from working. If none of this works, get a ammeter and see if your phone draws any amperage from the charger. After that you need to check and see if your motherboard even gets power. For that of course, you need to open it up.

Since iFixit doesn't yet have a guide for this, use something like this one to work on it. Your P300 uses a DC In jack that is separated from the motherboard and just plugs in to it. I would definitely consider replacing it. You'd be looking for something like this

If you get hung up on anything or run into challenges, post a couple of pictures of what is going on, with your Question. That way we can see what you see. iFixitでの質問に画像を追加する方法

While you work on your computer, take lots of pictures. Once you are done with it, take those pictures and create a guide for iFixit. That will help the next person that has the same problem as you do. It's easy and fun to create these guides. https://ifixit.com/Guide/new The iFixit community will appreciate this.

Repair is War on Entropy!

Hi @aftaster

If you are getting 19V DC between the red and black wires on the output cable plug attached to the DC-In jack then there may be a problem on the motherboard.

If the motherboard's model number is DABL5MMB6E0 then here are the schematics for the board.

Go to p.31 to view the circuit and start checking the components on the VIN path on the right and left sides of the drawing.

Hopefully a start.