this is ProBook know them and elitebooks well, they are my favorite, as for 2 things, last for ever, and rugged.
and HP documents on this are FABULOUS GRADE and DEEP
202 page service manual at hp.com for your PC.
a 2009 PC.
is the FAN DEAD inside>? I BET yES. (This is first thing to know)
that charger is really just a raw DC power pack
120vac (usa) to 19vdc raw DC power.
the charging magic (a chip) is inside the PC. a key fact to know.
forget silly/ lame LED lights. they get confused at drop of hat. ok?
1`: remove the big battery off bottom of PC, (easy no?)
2: run on the 19v battery pack alone, even forever is allowed. hint.
3: does PC run ok now? yes/no......
4: yes, then the RTC coin cell battery is dead, non go 10 years sorry, not going to happen ever, if marginal it FAILS NEXT., ok.
5: new RTC battery, AC only we next go in to bios. page 96
in the manual covers this.
6: does bios work now? power on and hit esc , over and over
page 116 in the service manual covers how to reach BIOS.
ESC then F10 (hammered at power on act)
if the fan is dead BIOS will be too most times.
if he fan is packed in lint as all are this old then the PC overheats.
all do that, this old. everyone not parked for 10 years as a hanger queen.
that is just 1/2 the story fixing ANY laptop really.
we can go to phase II , next , testing the HDD,
or cleaning out the junk here. LINT
see that radiator, oops. big trouble that.