Our HP Pavilion a220n tries to start up but turns itself off or sometimes hibernates in the middle of booting up. Although I got it all the way to the login screen once, it then shut off again. It is not stable enough to use or to copy our files over to a new PC. I've eliminated as causes the power supply and the AC cord. Because sideways pressure on the switch assembly can cause the problem, I assume I need to replace the switch. The faulty power switch is Part # 5187-2439 and includes a plunger microswitch, 2 LEDs, 8" cable and connectors. The power switch assembly doesn't seem to be available from HP or third-party sources after 8-9 years -- big surprise! Does anyone know of a plug-compatible generic replacement power-switch product that I could install to replace the faulty part? An external pushbutton outside the PC box would be fine - it doesn't need to integrate with the front panel pushbutton. In this PC, the power switch cable and 2 LED cables end internally in a 2-by-5 female plug that plugs onto pins on the motherboard. I can provide more description of the connector if needed. Barring a plug-replaceable switch, I'll probably hot-wire the 2 switch wires to a momentary pushbutton switch from Radio Shack. Thanks in advance...
Why guess, why not say power problems and leave it like that.
simple,
bah you can buy used part for HP of ebay all day long
but why, first find cause. but that switch stock , oh boy../
that case switch is just a SPST norm. open momentary switch
you can remove it and jump test the wires easy.
super easy test. if the powersupply over loads it turns its self off
the
the logic takes over after that, that simple switch is just momentary,
dig?
first first off say its a DESK tOP, ok? so others dont need to look it up or guess wrong, some here (kids) never seen one ever.
"its a brave new world" no?
wow a year 2000 desk top 17 years old, and almost runs
take a photo and frame it
has a value of what $5 or as seen in deep racks of goodwill
nobody wants. endless used ones parked in attics.
or sent to 3rd world as gifts but i digress.
path of logic
switch momentary
MOBO sees that and with gates, turns on the PSU.
the PSU comes up, and if not overloaded
the PCU sends PowOK signal to mobo
and mobo holds up power.
they work as team , logically
and if the MOBO sees shutdown from windows
it can reverse that gate logic and shut off.
as we all see every day.
bad PSU can shut down if bad. all can, psu bad
or if the overload is real. by ATX design.
SOME mobo can to for other reasons
like fans dead, or CPU overheated.
my top tier, ASUS mobo does All that and more.
even has a tamper switch, option.... full features in mine.
some pSu can shut down for dead fan or overheat or both.
mine can , i use high end PSU.
what is inside the HP, mobo is anyones guess
they dont publish to that level, like mine is..... and why I build all my systems(DT)
so when working any DT keep all that in mind
its not as simple as most think, it seems
the switch is just a REQUEST for power.
or if pushed 2 times, the reverse, but is programmable THAT..
here is my 2 power pins
on the mobo (not yours)
i unplug the pwrsw jack
i short the 2 pins, there,
power stays on my switch is bad. EASY NO?
oddly the last line in your post solve it.
a generic switch, momentary.
but you can do that with 2 ***** wires in hand
if ok switch bad.
if not ok , not the switch,, 5min work.
199 views
Usually answered in minutes!
The suggested solution with 2x5 motherboard pinouts is the beginning of a solution to my specific problem. Those pinouts do match the pinouts for my switch assembly. If generic power switch assemblies matching this pinout are available, that would solve my problem.
SOLVED. See other copy of this question, "Replacement part for HP Pavilion a220n on/off switch?"
×