Power_Jack_Acer3000Symptoms of a broken power jack:
The laptop only runs when you keep the power cord in a certain direction.
The laptop only runs on battery power.
The laptop will not charge the battery.
The laptop switches from AC power to battery power intermittently.
The unit suddenly shuts off
Sparks come out of the back of the laptop.

How jacks break:
- Some power jacks fail under normal operation of your computer. After a year or two of usage, parts just ‘come loose’ on certain models.
- Sometimes the laptop gets dropped and the cord yanks the jack loose.
- People, pets and vaccum cleaners all trip over laptop power cords on a daily basis.
- The laptop is moved around a lot. After the jack is moved back and forth enough times, it comes loose.

Most power jack issue can be fixed by resoldering it.  In some case you’ll have to replace the jack itself.  You can get most of the jacks for under $10 online.