The usual signs of that are:

1. The battery is not charging properly or stays at half charge despite that you have been using the power adapter.
2. The screen flickers (the brightness is changing) while the power cord is plugged in. This is caused by the laptop switching between DC power (screen is brighter) and battery power (screen is dimmer).
3. The DC plug gets hot after a few minutes of use and may even smell of burning.
4. There are “scratching” sounds coming from the DC jack.
5. No power - will not turn on (dead), although the unit will still work if the battery is charged
6. Unit randomly switching from AC to battery power and back
7. Intermittent battery charging problems

We do Power Jack Replacement Service includes:

• Replacing bad DC Jack with the Replacement Part
• Complete Motherboard Circuit Check Up
• Final System Test and Diagnostics
• External Laptop Cleaning