The laptop's AC adapter provides power to the laptop and charges the battery. However, it is very easy for the laptop adapter to have some problems with the frequent use of the laptop. In fact, if the adapter is having problems or failing, it can produce several symptoms to indicate that it needs to be replaced. Failing to replace a faulty adapter can be a fire hazard or hurt your laptop. Take my own HP 384021-001 Power Adapter for example, I would always check the following aspects:

Generally speaking, the first important aspect is the battery charge. A faulty HP 384021-001 Power Adapter may fail to charge your laptop battery or it could reduce the effective battery life of your laptop battery. When a laptop adapter is failing or has problems, it can create power surges that make the battery charge unevenly. If your battery is not charging at all, this is usually a problem with the adapter instead of the battery.

Also it may caused by random shutdowns. The HP 384021-001 Power Adapter is failing includes random power surges. Surges and power spikes may sometimes be hard to detect, but if your computer is not powering up properly or randomly shuts down it may be caused by the power adapter. This symptom may be hard to diagnose, as many other computer problems can also cause shutdowns. Run your HP laptop on battery to see if the computer still randomly shuts down. If it runs fine on the battery, the problem lies with the adapter.

Last but not least, there would also be some Physical Problems. If the transformer on the HP 402018-001 ac adapter has any wear, tear, cracks or other physical defects, it may be unable to work correctly. If the adapter cable is frayed or torn, this can have the same result. A broken power adapter can constitute a fire hazard, as the adapter may cause sparks. You can also be hurt badly if you accidentally touch a bare wire on the adapter. When this type of HP adapter problem occurs, you need to have the entire adapter replaced.

If the adapter is confirmed to be broken after the detailed check, we would usually go to to buy a completely new one. There are a lot of hot laptop parts here, such as: HP 432309-001 AC Adapter bullet(Output: DC19V 4.74A Power: 90W ) Gateway AK.065AP.004 AC Adapter(Input: AC100-240V (worldwide use) Output: DC19V 3.42A Power: 65W) Toshiba PA3237U AC Adapter(Input: AC100-240V (worldwide use) Output: DC15V 8A) Toshiba PA3237U-2ACA AC Adapter(Input: AC100-240V (worldwide use) Output: DC15V 8A) Toshiba PA3237U-1ACA AC Adapter(Input: AC100-240V (worldwide use) Output: DC15V 8A) Compaq PPP003SD AC Adapter(Input: AC100-240V (worldwide use) Output: DC18.5V 6.5A )