The laptop charging circuit is located in the main power supply source. It transfers the power from the AC adaptor to the laptop battery. The charging circuit provides a constant flow of power to the laptop battery so it stays charged. Laptops require a steady and large amount of power to stay charged and run correctly. Problems with the laptop's power source are usually expensive to repair, but it is possible to replace the laptop's charging circuit on your own.
Turn the laptop off and unplug the power cord from both the laptop and the electrical socket. Close the laptop screen and turn the laptop over so the bottom of the machine can be accessed. Place an antistatic strap around your wrist before you begin so no electric currents or shocks damage the inside of the laptop.
Press the release lever on the underside of the laptop to reach the battery pack and remove it. Screwdrivers will typically be used in order to take out all of the laptop's internal hardware including the hard drive, memory, CD drive and wireless modem. Disconnect a series of cables and an antenna to remove the wireless modem.
Remove the laptop's bottom casing using a screwdriver. The keyboard should also be disconnected and removed using a screwdriver. Unscrew the connectors fastening the display screen to the lower part of the laptop. Remove the display screen in order to gain access to the motherboard.
Remove the cooling fan and disconnect all of the cables that are fastened to the charging circuit. Consult documentation provided with your laptop to see exactly where the charging circuit is located. Use a screwdriver in order to remove the charging circuit from the base of the laptop. Insert the new circuit board.
Rebuild the laptop in the reverse order in which you took it apart. Make sure that all of the screws get replaced and the internal components are connected solidly to the laptop. Plug the power cord into the laptop and an available electrical socket. Turn the laptop right-side up and turn the laptop on and make sure that everything is working correctly.
The laptop should always be unplugged from the electrical socket before any maintenance work is performed in order to avoid serious injuries.