My laptop battery will not charge above 24%

[OldStick1]

I usually use my laptop plugged in to the charger... I understood that there is a protection built in to the battery so that after charging to 100% the battery disconnects itself from the incoming charge. Recently I noticed that the battery stops charging at 24%. I found a battery check program from HP but the battery checker says it cannot find my battery. Any ideas what could be wrong? Anyone?

[Lil_Boy_Blue]

Hi
First:- Turn off the computer, press and hold the PWR button for 4 seconds.

Then - Leave only keyboard and mouse connected, disconnect all externally connected
devices such as Docking Station, USB storage devices, displays, and printers.
Unplug the AC adapter from the computer.

Next - Press and Hold the Power button for 15 seconds to Hard Reset.
Rinse and Repeat

AND/OR - Power on your PC, press Esc (repeatedly), then F2 at the prompt.
Choose System Tests (Fast Test does a 4 minute hardware check).
AND/OR
HOW DO I USE DIAGNOSTICS?

HP PC Hardware Diagnostics Windows is a Windows-based utility that allows you to run diagnostic tests to determine if the computer hardware is functioning properly. The tool runs within the Windows operating system in order to diagnose hardware failures. HP PC Hardware Diagnostics Windows comes pre-installed on new HP computers, but if not on yours, download here:- http://ftp.hp.com/pub/softpaq/sp93001-93500/sp93457.exe

[OldStick1]

thnx - I'll give this a try and post the results here....