Hello room.
I finally found a nice laptop I could afford on Ebay.I took a chance and bought this one : Hp Laptop .It looks like new and came with everything as when new in the original box.

I ordered a new keyboard,replaced it last week,and everything worked just great,including the integrated wireless card.I was really happy to finally get one.I have a new battery coming Monday for it also.

Well,my daughter was anxious to try it yesterday,so I let her but she accidentally tripped over the power cord and unplugged it will it was on and being used.When she plugged it back in ...NO POWER!GRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR!

Needless to say I'm very disgruntled.The only light that comes on now is the amber battery light.It flashes on and off when the battery is removed.The battery would'nt take a charge,so I've always left it in the laptop anyway until my new one arrives Monday.This light used to stay on steady all the time,whenever the laptop was plugged in.Now it only comes on and flashes when the battery is removed.The instructions says this is normal when theres no battery installed

Anyway,now it won't power on when pushing the power on button..The AC adapter calls for 18.5v output,my multimeter reads from 17.2v to 18.4v.It jumps back and forth between these voltages.

Should I try a new AC adapter?Or as I dread,something more serious has malfunctioned/went out?Any suggestions would be appreiciated.I can't find any specific answer to this on the WEB.

Thanks in advance.

Well,I have a sneaking suspicion that its my AC adapter.When I push the power button repeatedly in a darkroom,the blue power button will light up very faintly/briefly,as if its barely getting enough voltage to turn it on.Since my multimeter is showing the voltage jump back & forth from 17.2v to 18.4v at the AC adapter,maybe this is the trouble.It calls for 18.5v.

I can get this one on Ebay for relatively cheap: AC adapter

Should'nt my current HP AC Adapter put out a steady 18.5v or slightly higher?

Any thoughts?

This is the power symbol that briefly lights up,from the HP website:

power on symbol

i have a HP laptop that i bought new, and one day after a power blackout it would not turn on and the power light did the same thing you described, i had it sent to HP for repair as it was under warranty and it had its motherboard replaced.

I hope its not your motherboard, but it sure sounds like what happened to my laptop.

Good luck on repairing it!

Thanks Phife.I can get a used working motherboard off Ebay but that will be my last resort due to the high price of even used ones.As I've learned from many DIY projects,you can put more time & $$$ invested in used,when its better to just get new if your not careful.

I used to troubleshoot HP laptops.

Unplug the AC adapter and take the battery out of the laptop.
Press and hold the power button for 10 seconds (with no power to the laptop). This drain any residual electricity that might have built up in the capacitors. Sometimes this does funny things to the laptop.
Leave the battery out and plug in the AC adapter, then push the power button. If it powers on, you can try replacing the battery while it's still on.
If it still doesn't power on, try a replacement AC power cord. If it's a two-piece cord, you might want to order both pieces, just to make sure.

If it still doesn't power on, you'll probably need to replace the motherboard.

Thanks Quasi.I tried your suggestions,no help....yet.When I leave the battery out,the amber battery light will flash off/on continuously(manual says this is normal when battery is removed),but power button light still stays out or faintly lit.I'm still waiting for my new battery from Cali and a new AC Adapter from Indiana.Both -should- be here Wednesday 4/29/08.I'll post my success or failure asap when these arrive.Until then,I'm glued to my OLD trusty desktop.

For all their flaws... this is one area Apple actually came through big-time for me. The MagSafe power adapter on my macbookpro. I went through no less then 4 AC adapters, and the ac jack eventually broke all-together on my previous laptop, so I feel your pain. Good luck!!

Well,I got my brand new battery and AC adapter today.I put the new battery in,without the old or new AC Adapter connected,hit the power button,and if fired right up!Everything works normally except the screen was a little darker than normal and I noticed the battery indicator light was'nt on,so I did a battery check in the lWinXP control panel.The battery is only at 58% charged,which should be normal I guess without a full charge from the AC adapter.

Well,I shut down the computer and first plugged in the -new- AC Adapter.Again,no battery condition indicator light came on,on the front of my laptop,which SHOULD have occured.These lights tell the user what is going on.A steady green for charged,a steady amber for charging,a blinking amber for dead battery.
I immediately tested the -new- AC adapter at the plug with a digital multimeter and it reads a steady 19.2 volts.I again fired up the laptop with this -new- AC Adapter connected(with new battery still installed) and theres was no change,its as if the new Adapter was'nt even connected.

Frustrated,I decided to try the -old- AC Adapter.I shut down the laptop,connected the -old- AC Adapter with the laptop off.Again no battery indicator lights came on.I fired up the laptop again(with new battery still installed) and all went well except for the darker than normal screen and no battery indicator lights coming on.

Well,every 20 seconds or so,I started noticing the screen would momentarily flash brighter(with a normal looking screen) and the amber battery light would come on(charging) at the same time,for like 3 seconds or so,then go off,wait 20 seconds,then same thing again and again....etc.The laptop obviously has issues with the AC Adapter or a weak/leaking capacitor or diode on the motherboard??????????????

The -old- Ac Adapter is fluxuating between 17.2-18.4 volts output.But the the -new- one doe's NOTHING to the laptop at a steady 19.2 volts output.Why doe's the -old- one seem to work and the -new- one does NOTHING?

This laptop calls for 18.5volts so I think BOTH of these Adapters should be within the required + or - voltage range or am I wrong?

If I'm correct that these AC Adapters are working properly,then my only option is to tear down the laptop and find the bad component.The computer does'nt need the whole motherboard replaced,as its obviously got a minor part that is'nt functioning.

Maybe I should'nt have bought the cheapest AC Adapter?It seems to be working as its supposed to.

Thats where I'm at so far.Any more suggestions are appreciated.Its gonna be a rainy weekend up here in Michigan so I'll be working on this working on thing in any case.NOTHING NEW AROUND HERE THOUGH,it seems I'm always having to FIX something

lonewolf

I found this one on Ebay,its identical to mine.This should save me alot of trouble if I win it.The shipping is way high though.These things only weigh 8 pounds.

laptop

The solder on ac plug inside the laptop might have been knocked loose. If you can plug it in to the AC power then wiggle the connector at hte laptop, see if the light turns on or not. OR If you feel up to it, you can try removing the case and check it out. had to replace one on a toshiba one time.

You might also be able to test it by pluging it in and using a multimeter to test for power at the battery terminals. If that makes sense.

Just like Venom said, try plugging it in and then moving around the ac connector where it connects to the laptop. My friends laptop will only charge if the plug is held a certain way.

Hello again.I disassembled the laptop,a You Tube video from KastenTech helped tremendously in this procedure as it was almost indentical to my HP 5300,his was just a little older HP model of the HP 5300 series.
The power plug input was tight on the board with strong/clean solder joints,and I did a continuity test that tested OK, to be sure.I removed the fans/fan housing assembly(3 fans!) off the CPU,cleaned everything with clean compressed air,as they were somewhat dusty.I blew off the motherboard and unplugged/re-inserted all electrical connections.I applied new heat sink compound(Artic Silver) to the CPU/heatsink and reassembled the laptop.No Help.Its still running on battery OK,and when the AC Adapter is plugged in,the screen will brighten and the amber charging light will come on for 3 seconds,then go off for 20 seconds,repeatedly.AS I mentioned before,the voltages on the Old HP Adapter jump from 17.2v to 18.4v continously on my digital volt meter.The new Non-HP(cheapie) one puts out a constant 19.2
Well..... I decided to try a brand new Genuine HP AC Adapter after contacting HP support and will recieve it Friday 5/9/08.It costs substantially more than the new cheap Non-HP one I bought.They said most aftermarket AC Adapters would'nt work due over voltages and fluctuations in voltage.It must be a constant 18.5volts and this laptop has a "PFC" circuitry which will disable the AC functions if the voltage is too much below or above 18.5volts,according to them.
Anyway,this laptop is worth salvaging to me and if this don't work,then I'll just have to cut my losses and get rid of it.
I'll post the results on here Friday and hopefully I'l be a Happy Camper with my 1st laptop again!

lonewolfmichigan

Also,I did'nt win the auction on the Ebay laptop.
It went for more than I thought it was worth.If the sellers shipping would'nt have been so ridicously high,I would have paid $65.00 for it,just for the parts.

But as my better half said,why put gobs of money in a 4 year old laptop anyway?

Your 'new' adapter might not have a high enough current rating, and the voltage drops too much when the laptop tries to draw current. As for the behavior with the old one, I have no idea.

Good luck with that HP adapter!

Well,SUCCESS!The Genuine HP AC Adapter made the difference and I found out why.
The 1st cheapie replacement AC Adapter I used had the wrong size plug-in.**I've linked a picture to it below.**
It was somewhat shorter in length than what was called for.Thats why the cheapie one would'nt work.I took apart the cheapie replacement Adapter AND the defective Adapter that came with the laptop.I unsoldered the cords on both and soldered the plug-in cord from the defective adapter onto the cheapie replacement.Even though the cheapie one has a higher than required voltage,it seems to power my laptop just fine now.
Now I have 2 working AC Adapters!I'll use the Genuine HP Adapter and keep the cheapie as a back-up.
I went through alot of headache over this for a mostly easy solution.I guess the thing is to make sure the plug-ins are EXACT whenever replacing a AC Adapter.The old adage holds true."you get what you pay for" and that cheapie replacement had the wrong size plug.I should've noticed it right away instead of taking for granted that what I paid for was correct.Thanks for everyones help and support!
Heres a couple links to pictures:
Plug-ins.The one on the left is correct


opened AC Adapter


my laptop working again!

While I was working as HP Tech Support, after a customer called in and said their laptop would not power on after buying a replacement AC adapter, the first question I always asked was, "Did you buy the Adapter from HP?"

I would have mentioned that you should have bought it from HP (or at least the same part number from another vendor) but I had assumed you did.
For future reference, you can take the HP part number (6 digits followed by a -001) and Google it for a better price from another online vendor.

On a side note, those other adapters could probably be used to provide power to your next projector's LCD.

Thanks Quasi.I've learnt my lesson about buying non-OEM parts that are a high priority component in any given piece of equipment.
HP asked me for those numbers, that was the first thing they asked for,so you know what you are talking about.

I still have'nt finished my projector project yet.I'm waiting for my 'tax stimulus' check and am buying a better quality silver colored screen for it.The white one I bought just does'nt compare to the silver ones for better brightness,in my setup anyway.I have an old silver screen from the 70's and tested it on my projector.The difference was amazing.Ihad half the picture on a white screen,the other half on silver and theres no doubt the siver looked 100% better even with greater contrast.

But anyway thanks again and your tips were helpful.

lonewolf