Failing to power up.

http://www.fixya.com/support/t634376-amw_t_352_dolby_digital_home_theater

why not post to hp with this old thing, nobody uses. now.?
sure garage sale most are in the trash long ago.
buy used cell phone and end this misery?

find a manual, read it?
hp dont have hit now, this product is RETIRED
that leaves deep google lucky finds.

here ill google for you,
https://duckduckgo.com/?q=3150+iPAQ+manual&ia=products

i boycott google so... that.

or ask here, at HP REAL

https://h30434.www3.hp.com/

watch out for giggles, and ZINGS !

like where did find this , at Goodwill for a $1
or less?
infact go there find good PC for $20 and end this PDA thing.
surely you are not spending cash on it for a new battery right?

Hello i'd be happy to help :-). Since you said that you bought a new battery and it still didn't work. I am guessing that you might have charged you Ipaq by pulling it into a regular wall outlet . This is bad because that outlet could send to much electricity into the Ipaq and can kill it. That might be the problem why your Ipaq is not working... I would recommend for you to call HP and see if you can return your Ipaq to them and see if they can send you a new one. 

Try taking out battery and plug in power. If it works, battery is faulty. If not,
Try taking out your hard disk plug in power, if it works, hard disk is faulty. If not,
Try taking out memory card, if there's a sound, memory card faulty. If no sound, it's your motherboard that is causing the error.

Note: If machine is under warranty no need to pay for the repairs.

recharge the battery by connecting the HP iPAQ to AC power using the cradle or the AC adapter to atleast 6 hrs continuously 

How to correct iPAQ 5450, 5455, 5550, 5555 battery charging problems / dead unit syndrome.

The iPAQ 54xx or 55xx will not power on if the batteries charge is lower than 3.2 Volts, if your battery charge falls below the 3.2 volts level your unit will not turn on, you need to plug the iPAQ into a cradle or AC charge adaptor. Note the charging light on the iPAQ will not flash at all (normally flashes orange) until the battery charge has reached a minimum charge level of 3.2 volts. You then need to perform a normal reset, then the unit should switch on normally.

HP Procedure is as follows:

To charge and reset the iPAQ Pocket PC h5400:

i) Connect the iPAQ Pocket PC h5400 to an A/C power supply.
ii) Charge the battery to the minimum level of 3.2 Volts. This will take 5 to 30 minutes depending on the current charge level.
iii) Perform a normal reset.
iv) Power on the iPAQ Pocket PC h5400

It is recommended that you keep the iPAQ Pocket PC connected to the Universal Cradle or Cable when it is not in use.

When you charge up your iPaq, do you use the cradle, or do you use the AC-adapter with the little iPaq power converter that came with the iPaq? Try both, and see if it charges up your pda. Try and borrow an iPaq car-charger and see if it charges up that way (the ones that do not need the iPaq power converter). If you are lucky enough to power up the iPaq even for 2 minutes, enable USB fast charging in the SETTING -> BATTERY. Your USB-data-cable or cradle will then be able to charge it up that way...