Service manual to dismantle and replace power supply on HP Pavilion ZT3380

Does anyone know how to replace a power supply in an HP Pavilion ZT3380
laptop please?

The power plug seems to be exceptionally loose and if the computer shuts
down, you can occasionally get it turned on again by turning the plug around
in the socket 180 degrees so that something makes contact with something
again. But I don't think this is the whole story.

The computer does work as a desktop but once it did shut down overnight for
no apparent reason and once during use while I was trying to soak-test it
for this very problem. When it shut down overnight, by the morning, when I
turned it on, the orange charge light having presumably been on all night,
it showed 0% charge. Suspicious.

More importantly it shuts down completely if you accidentally jiggle the
plug, not going to battery power at all. In addition, when you start it with
a largely dead battery and then try to plug it in to charge the battery, the
battery doesn't charge at all. It CAN also show an orange charge light
overnight when off and by the morning, show no increase in charge: This
doesn't just seem to be a loose plug!

I upgraded the BIOS and this seemed to improve things for a very short
while, with the new BIOS having a battery calibration utility which worked
once. However, now it wont even charge the System Battery except
excruciatingly slowly. Isn't the system battery something like a
rechargeable CR2025? Which should discharge/charge in a few minutes. When
the battery utility did discharge/recharge the main battery, it did do it in
around a half an hour.

We HAVE tried changing the AC adapter in case the problem was with the
internal wiring of the plug itself and isolated that as not being the issue.

Someone once referred me to a service manual for my Pavilion 5415 which had
a similar problem but I cant now find the reference to it (and replacing the
power supply for the 5415 involved a completely uneconomical taking apart of
the whole computer down virtually to the last screw!). These internal power
supplies do occasionally come up on ebay and sell for a few bucks. possibly
for this reason?

Hopefully the situation wont be the same for the 3880? Though an alarming
number of them seem to come up very cheaply at places like Fry's, -
reconditioned .

(Incidentally it refers to itself on its screen panel as a ZT3000, on its
underside as a ZT3300 and on it serial number plate as a ZT3380US)

 

A CR2025 explodes if you charge it.

It may just be a contacrt problem. THese are best tackled with contact
spary and bending the contact so that is presses firmer on the plug.

Arno

 

Yes, I suspected that: So the problem may well be with the CMOS battery
itself? The utility at first stopped the charging process at 99%.
Thereafter, it wont get much past about 8-10%. I wonder if this could
account for the whole problem? (see below)

Actually when I now go into the BIOS utility, I am not offered the option of
calibrating the Main Battery any more (I did go through the process of
recalibrating the main battery, - successfully, - once), just the "system"
one

The reason why I included such an amount of detail in what could be a
contact problem is because MOST OF these symptoms don't seem to point to a
contact problem. Such as: Why can't it switch from ac to (a fully charged)
main battery like all other computers when you simply take out the plug? Why
does it shut down completely when you arent actually doing anything on the
computer if it is a contact problem? Unless the contacts inside the socket
are completely burned out, carbonised and pitted, why doesnt it charge the
battery on re-plug in if it is just a contact problem?

If it IS just a contact problem, surely just spraying it with WD40 will make
the problem completely go away for at least a while until the metal under
the 'oil' starts encountering the carbon again? And for fear of repeating
myself, why am I getting all these mysterious problems with the calibration
utility if the problem is with the contacts?

 

Sounds like the power connector is coming loose from the main
motherboard. Not uncommon with a laptop. Especially if it was ever
banged around with the charge cable connected. If it is coming loose it
can cause ALL the problems your seeing. You need to open the machine and
resolder the connections, or replace the power connector itself it it is
damaged.

The connector is not JUST a connector, they usually have a couple of
switches inside as well as the charger circuit having current and
voltage detection as well. With the loose connections you get the
symptoms your seeing. One time the charger works fine and the battery
gets charged, the next the machine is dead because it doesn't get power
from either source. Then you get the

Dell, HP and Toshiba all have had this same problem at one time or another.


--
Steve W.
Near Cooperstown, New York


--
Steve W.
Near Cooperstown, New York
NRA Member
Pacifism - The theory that if they'd fed
Jeffrey Dahmer enough human flesh,
he'd have become a vegan.

 

Hmm. Agreed. Sounds more like an issue with the entire power unit
in the laptop. Maybe a swithcing transistor that has a problem or
the like. Very hard to diagnise without shematics and the right
equipment.

Arno

 

Contacts are self cleaning. That applies both to connectors and to
contacts on battery.

You are speculating what is a problem; then trying to fix based only
on speculation. In but minutes with a meter you (or those who can
provide better information) would know rather than just speculate.
Everything posted is just speculation. Anyone with sufficient
technical knowledge to provide a useful answer will post nothing -
because no useful facts have been provided.

For example, what is that battery voltage? Now we can say if the
battery is charged. What is battery voltage when connected in system
or voltage on connector to that battery; measured when AC power is
applied and is disconnected.

Why are you getting weird calibration problems? Nobody who could
answer that question will even post because you don't provide numbers
necessary to answer that question. First essential numbers are in the
previous paragraph.

Meanwhile, WD-40 is a worst solution possible. Contacts are self
cleaning. Those with sufficient knowledge to answer your questions
would have also noted why contact contamination does not exist.

Is power supply a separate board? That would be unusual.

Meanwhile, money spend on the power brick also would not be wasted
had you used the meter and one minute to make those measurements.
Just another exmaple of why fixing things only based in speculation is
money wasted.

 

Actually I am not the one who spent the money but the reason I posted was
obvious: to find out (from someone who knows the way around the HP web
site) where the service manual is. This will tell me how to establish
whether the power supply is separate and/or how to get it out to replace it.

Again, obviously, once inside I may well be able to figure out whether the
contacts can be rendered more secure and the problem completely solved. Look
at my carefully worded header.

Without taking any voltage calibrations.

(At the moment I don't even know how to crack open the case. And my
suggestions as to what might be wrong with some carbon build-up on the
connection was not designed to be taken seriously, else I would be able to
see at least some pitting at least somewhere)

 

Have you ever actually worked on a laptop computer? It's no where
as simple as you make it out to be.

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You haven't come across w_tom before, then? Just don't mention
lightning...

 

That is what I sorta figured from his assertions that one has to do complex
voltage measurements of minuscule internal parts (which you can only get at
once you have cracked the case) in order for anyone to answer a question on
where to find a service manual so that you can crack the case!

 

The power jack on the notebook has separated from the mainboard. This
is not unusual for HP notebooks. The jack simply cannot withstand the
forces of insertion and removal of the AC power plug.

If you are skilled with a soldering iron, there is a good chance that
you can figure out a way to either re-solder the power jack to the
mainboard, or solder a pigtail to the mainboard input power traces to
move the AC adapter jack outside of the case.

Otherwise, it is a mainboard (or sub-board for the jack) replacement,
and good luck working with HP on that!

Q

 

Had the same issue with a Compaq Laptop.

 

Try eBay:-
HP Pavilion ZT3000 service repair manual 0n CD US$9.99

Good luck! Colin

 

This is pretty much exactly the symptom I am noticing: I just posted here to
see if it was a common problem others had faced with this notebook; and if
possible how others have dealt with it.
This

Sine ci Posted, a friend has told me that he has exactly the same problem
with a few HP notebooks he has!!
The jack simply cannot withstand the

Arent they all made in the same Quanta factory in Taiwan?

Sorry to repeat myself or sound naive but how do you get to the mobo?

I had already spoken to them and they gave me a load of fluff lasting about
20 minnutes prior to telling me that the power supply is on the motherboard
and replacement will cost four hundred bucks because they have put too weak
a jack connector on their laptop. Is this why there are so many refurbished
ones coming onto the market? Does Consumer Reports know about this problem
and how HP both cant re-solder one connector to the motherboard and/or power
supply AND treats their already-sold computers like mini-profit centres?

 

I believe you are confusing w_tom with news.rcn.com. The latter is
going to open a laptop, look at a power supply, and know whether that
power supply is defective on sight. He is going to solder a loose
connector but even declares voltage measurements with a meter as
complex. He is even going to *fix* bad electrical contacts with
WD-40.

He wasted money replacing a power brick ony because he speculated it
might be bad rather than do what a 12 year old even does - use the
meter. The meter being so simple that it is even sold to K-mart
shoppers.

news.rcn.com does not even know how to open a laptop but somehow
*knows* the meter is too complex. Meanwhile, if he had used the
meter, then basic information on power supply operation, power
connector, and battery state could have been learned without opening
the laptop.

Most interesting is the speculation. news.rcn.com has assumed the
power supply will be on a separate board. I have yet to see that on
any laptop. But then news.rcn.com is using speculated symptoms to
know what is wrong.

If news.rcn.com cannot use a simple meter, then he most certainly
cannot use an iPod. Therefore he is the last person who should be
opening a laptop. Appreciate why HP would fear letting too many have
service manuals. Somehow news.rcn.com is going to look at a power
supply board and visually know it is good or bad? Well had he taken a
few voltage measurements without opening the laptop, then his replies
here could have been far more useful. Currently every reply is only
speculation. Even more absurd is that he will reflow solder on a
connector - but fears the multimeter as too complex. He will fix a
connector with WD-40. Others never questioned his technical grasp?

 

....snip...
Some PCs have non-rechargeable system button cells that can simply be
replaced.

Sounds like you have a bad NiCAD/NiH battery and bad connections. On my
Compaq (aren't Compaq and HP the same these days?) the socket is notorious
for coming completely loose from the motherboard resulting in the whole
thing failing. My PC was dismantled carefully, the socket soldered back
with some suitable copper wire where the MB contacts had failed and then the
whole socket epoxied to the motherboard for further strenthening. Should it
fail again, I'll never be able to repair it again but frankly I've repaired
it once too many times for my liking already.

Paul DS.

 

I am in exactly the same position: We have established that the connector
between the mobo and power socket does come loose on these HP laptops and
then presumably the power in stops providing power to the rail comprising
the CMOS battery charge circuit. There might well be nothing wrong with the
(reasonably newish) CMOS battery. Since this time I have spoken to a
friend in New York who reports that he had exactly the same problem with TWO
of these computers bought for his kids! I dont think there can be much
doubt any more about what is causing this, despite some responder's mention
of the need to check voltage measurements before soldering back what
everyone seems to agree is the broken connection.

Where did you find someone to do the repair? Or if you did it, was the
soldering a difficult one comprising lots of tiny connections?

 

Take a look at HP's customer service area, especially to
http://search.hp.com/query.html?lan...n+zt3380LA+Notebook+PC+|+service+manual&la=en
A mfr will build several models from the same basic computer chassis, putting in
a variety of features in an effort to extract more from your checking account.
The same service manual can apply to several different models. Look at the list
of manuals on that page and see if any fits your computer.
You'll likely find that the DC coaxial power connector has broken from the
mother board. The fix for this type of problem is usually limited to
replacement of the connector. These connectors are usually priced from around
$1 to $10 USD. The price of having a computer shop replace the connector can be
in the neighborhood of $100 to $200 USD. That's because of the labor involved
in disassembling the computer, replacing the connector, and then reassembling.
The service manual will give you the disassembly and reassembly instructions,
but if you don't have the necessary soldering equipment and skills, you can
easily destroy the motherboard. The choice is yours...

Cheers!!!
--
Dave M
MasonDG44 at comcast dot net (Just substitute the appropriate characters in the
address)

"In theory, there isn't any difference between theory and practice. In
practice, there is." - Yogi Berra

 

You are absolutely right and this is exactly what i have discovered: The
centre pin in the female socket is very loose indeed. I am just wondering
what I will find when I get in there to replace it. And is there a link
anywhere to somewhere to buy a replacement?

All the manuals which result from the page you reference look a bit like the
notebook I have: I wonder how I establish which one is correct or are they
basically probably all similar when they look similar?

I wonder why the 3380 manual doesnt come up when one does the search you
did, especially when the results page does indeed refer to the 3380!



The price of having a computer shop replace the connector can be

 

http://www.justmanuals.com