Compaq 700us laptop; replace powerjack

[Vickip]

Hey everyone...

I need some help replacing a power jack on the Compaq 700us laptop. It has broken completley off..and compaq does not sell them...they want you to purchase an entirely new motherboard.(although they should..seeing as how this seems to be a problem with a lot of them.)

I found one from a parter on ebay, but since I normally only work on pc's, I'm a little hesitant to just rely on my instincts here..

Any and all help would be appreciated!

and thanks in advance...Vicki


What if the hokey-pokey really is what it's all about?

[elmers]

>>>compaq does not sell them...they want you to purchase an
>>>entirely new motherboard

Thats pretty harsh. By power jack do you mean the end of the power cord that plugs into the lappy ?

[Vickip]

no...it's where you plug in to..on the motherboard itself..

and yes, it's very harsh! The cost of a new motherboard, plus the labor to install it is about the same as to buy a whole new laptop!

[elmers]

In that case you could open the case and solder another female jack fitting the power cord. It will definitly void the warrenty, but is a lot cheaper than replacing the mobo. Perhaps this can be done in a "official" manner so as not to void the warrenty by going to a recommended service center. I remember the same thing happening to my nintendo and my dad just replaced it himself. It worked allright and was done in 10 minutes.

[hockeyman12c]

I'm currently doing the exact same thing. I had to take absolutly everything apart and now I'am waiting for the 8 doller part. I hope it works.

[fixmyjack]

How to replace a dc jack**spam removed**

Fixing a dc power jack on your (or someone else’s) laptop can be difficult. If you are not sure what you are up against is a sure sign that you may not be able to reassemble the laptop. However with the proper steps, repairing, or replacing a laptop dc jack can be accomplished.

The following is by no means an official user manual or repair guide. This write up is a check list and a general guide to help you replace a dc jack without having to purchase a new motherboard or a new laptop. This is a guide, to help you decide whether you should attempt the repair, or ask FixMyJack.com for repair assistance.

Disclaimer: FixMyJack.com or its employee’s claim NO RESPONSIBILITY for anyone who fails in their attempt to replace a laptop dc jack or any damage laptops can receive following this guide. We are just trying to inform others from the steps we have taken for dc replacement and the possible blunders.

0) As step zero, it is important to make sure that you identify a bad dc jack. If a laptop isn’t charging when it’s plugged in combined with a very loose power jack port usually indicates you have a bad dc jack. We have also seen dc jacks that are just fine, however when looked inside, you see it has been physically destroyed on the rear end of the jack itself. Each case is mostly different, but you will run across 3 possible scenarios.

a) The dc jack has cold solders and it just needs to be resoldered (the most common).
b) The dc jack has been broken in unseen areas of the jack itself (common diagnosis is the wiggling of the jack with the adapter).
c) There is nothing wrong with the dc jack and it’s an issue with something else on board (uncommon, but it happens).

1) Do your research.

So you conclude that you have a bad jack. Find out what style or sort of power jack you need for the laptop. You don’t need to open the laptop to find out what type of power jack you need. Go to the internet and search for model laptop + dc jack. For example, if you have a Toshiba Satellite, search the internet for “Toshiba Satellite dc jack”. You will be greeted with some useful results. Not only will it give you results for dc jacks but they look like in general. It would not be beneficial if you ordered a random dc jack that doesn’t even fit inside the notebook.

At this time, it would be best to check to see if the laptop powers on. If here is enough battery life left, turn it on to ensure that the laptop works fine. It may be essential after reassembly which we will explain later

Some models like Toshiba Satellites will have a dc jack with different pin sizes. The pin in the middle of the jack will be a different gauge or different size. It’s crucial that you check to ensure that you get the correct jack size. Failure to do so will ensure you some problems when you plug in your Power adapter (ie: it won’t fit). When you receive your dc jack in the mail, fit it on the power adapter that goes the notebook to make sure that you received the right dc jack.

2) Prepare and gather the tools you need. Make sure you have the right tools for the job.

- Screw Drivers (different sizes and shapes)
- Paper
- Pen or Pencil
- Packaging Tape
- Soldering Iron (and soldering essentials)
- Volt meter (to check continuity)
- Basic electronics and soldering knowledge

Make sure you have different types of phillips screw drivers, flat headed screw drivers, hex screw drivers, torque screw drivers, etc. If you have never been inside your laptop, then you don’t know what to expect.

3) Visual overview and time to get to know your laptop. This one is what we consider an important step, but it can easily be missed.. Before are ready to disassemble a laptop, we always look at every single screw hole, removable piece and potential issues. It’s just a practice that we perform to help me remember where the nooks and corners are. Take about 5-10 minutes to sit down and rotate the laptop around and look at it in more detail.

Time to get started…

4) Remove the external devices. By external devices, this means the Hard Drive, Battery, PCMCIA devices if you have any, etc. When you remove these devices, you will see screws in new places and it will obviously make it easier to access the laptop when disassembly occurs. The CD ROM from a laptop, most of the time, cannot be removed at this point. When you start removing screws, it may be easier to remove the CDROM later but not in the beginning.

5) Disassembly and documentation of your steps. This is where the paper and pencil come in. The most important tactic you need to perform during the disassembly process is the documentation. We cannot emphasize enough the need to document where every single screw location and size.

The most general place to start disassembly is on the bottom of the laptop. It has the most accessible screws. Generally what you want to do is draw on a piece of paper a rough diagram of one laptop. Draw one side of the laptop per page. On the diagram, label where screws are located on the laptop. Be as descriptive as possible about the location of the screws and their location.

When you remove screws, use the tape to stick them near the hole where they came from. In case the tape fails, the diagram you draw will assist you in putting them back where they belong. Document the order in which pieces are removed. Another solution is to collect all the screws from a section, tape them in a little bundle and stick them in a notable location.

Some laptops have only 2-3 sizes of different screws. There are many laptops that have many different sized screws. Take the time and document where each screw comes from. IBM Thinkpads are nice. They actually have a sticker that shows the label of screws and screw sizes. It comes in handy. Some Toshiba's also have a label next to screw holes and give you unique identifiers.

Once again, it’s essential that you document each step you take during the disassembly of the laptop!

6) Handle with care. The Plate connector beneath the LCD is the most fragile piece of the laptop disassembly. That’s why we gave it it’s own mini-section.

It’s the most fragile because if you force to plate too hard, you will snap or damage it. Some models have it just tied down by a few screws underneath the laptop. Most models have a snap action to it. It comes in handy to use a very thin flat head screw driver to probe the plate. If the screw driver bends too much, then it’s time to probe in a different section. Please be cautious when doing this. A good place to probe is on the hinges where the plate overlaps next to the LCD hinge. When you start pulling up on the hinge from the corners, it will start exposing the parts underneath it.

(Note: The LCD display will not have to be disassembled fully. Just the cord and hinges can be removed alone. You do not have to get into the insides of the LCD.)

7) Motherboard access review. You’ve disassembled the laptop and you have the motherboard in your hands. Look at the dc jack and it’s connection to the motherboard. One issue we see with dc jack failure is cold soldering or failure in the solder itself. If there is not damage to the dc jack, the jack can be repaired by re-soldering the current dc jack in place. Some of the time, the dc jack itself is damaged and needs to be replaced.

8 ) Replace / Repair the laptop dc jack. If the dc jack needs to be replaced, use your soldering iron to heat up the solder from the dc jack and remove the old jack. If you have a dc jack with hooks or curves in the connector, good luck. We know how difficult it is when removing this type of dc jack, but with some patience and persistence, it can be done. When the dc jack is removed, clean the area (pin holes); then solder in the new dc jack into it’s slot.

Warning: Some motherboards have very thin rings around the dc jack connectors themselves. The older Sony Vaio laptops have them. If you heat the solder too hot or too long, these rings come off. When that happens, you might as well call it game over. These rings connect the dc jack to the motherboard using extremely thin connections. The rings are vital to the dc jack connection to the motherboard. It is very easy to burn, or break the system board during this process.

When you get the new dc jack in the slot, you have the option of putting hot glue around the corners of the new dc jack. It’s an option to prevent the dc jack from getting bumped and pushed too much from the ac adapter. It’s just added strength. Just don’t over-do it if you decide to put some on.

BE CAREFUL ABOUT THE CHIPS AND ELECTRONICS AROUND THE DC JACK!

People have destroyed chips on laptops because they were not careful when de-soldering and soldering. A sharper soldering iron is a better tool than a blunt rounded soldering iron.

9) Test your continuity. It sounds impossible, but you can test to make sure that you connected your dc jack correctly. Most volt meters have a continuity checker on them. Check to make sure the grounded section of the dc jack properly grounds, and if possible, check to ensure that the positive pin on the dc jack is properly connected to the motherboard. You can do this by touching some of the diodes on the motherboard close to the jack. You will know if it registers.

10) Reassembly with a little faith. This is the moment of truth. If you documented your disassembly well, then it will be your road map to reassembling the laptop. Start reassembling the laptop in the reverse order in which you disassembled it. Make sure you plug in every little cord, and ribbon back into your laptop. Disassembling the laptop again because you forgot a wire or ribbon is just annoying to the max.

11) Testing the laptop. Test the battery first to make sure that the laptop turns on without the dc jack. There have been a few situations where people have worked on their laptop and it didn’t turn on after they reassembled it. This is unfortunate, but it does happen. Sometimes you damage something during the whole process, but with caution it can be avoided.

Once you verified the laptop turns on with battery, then go ahead and plug in the dc jack. First sign it works is the “Battery charging” light turns on and you know you have a successful replacement. Another final test is to power down the unit, remove the battery, and see if the unit powers on with just the power cord.

At this point you can turn on the laptop and your job is complete. If your laptop doesn’t turn on .. well.. go back to step 4 and 5 and go from there. It can happen, but we haven’t seen it too often unless there are more problems with the laptop than originally thought.

We hope this article is helpful; and if you have any doubts please do use our services that we offer at **spam removed** Don’t risk damaging your laptop.

[techman_007]

Fixmyjack did an phenominal job in explaining the do's and don'ts in replacing the power jack. My hat is off to you. However, there is one other item that I think should be mentioned in the replacement.
Most motherboards are layered. I have seen as many as five layers with circuitry running on and through all the layers. As a matter of fact, the last motherboard I repaird, (replaced the female powerjack) had a very small piece of wire that was wound around the positive pin from the top of the board (wire wound on the top of the connector positive pin), it then ran through the hole with the wire parallel to the pin, then wound again at the bottom of the pin (the bottom of the motherboard). This connection was obvioulsly part of the main buss with connections made in the layers of the board.
One other thing should be metioned is that when using an ohm meter, whether digital of analog, you have to be careful when injecting a voltage to check continuity. Even though the current might be very small, keep in mind it only takes -0.01 to .07 volts to change the state of an IC chip from on to off. If your working around CMOS chips the voltage can go as high 17 volts before changing the state electrical state of AND gates, NOR gates, XNOR gates, ect. Even injecting 5 volts into a diode can cause a reverse bias, and run current where you don't want it. Usually there are op-amps that run in series to powerjacks to regulate voltages. This is just a simple reminder to take care when checking for continuity. If your using an analog meter, you can set the resistance measurments to RX1K. That will give you a very low current state instead of a full blown voltage, current charge.

have a great day
techman_007

[checkin]

Question with testing dc jack on my Compaq Presario V2000. I have it apart now, think I can avoid unassembly of the motherboard, fan, etc, by prying up the corner case just enough to get iron in.
It is still in circuit, no matter how I ohm it, it shows shorted with pos. & neg. dont know if I'm not doing something right or what. Battery I beleive to be dead, so could not test that to see if it powered up.
The jack is not loose, one or two joints may or may not be cold, but am curious if there is a sure fire way of testing the jack to find out for sure.
Also, how important is it for reassembly to try the power?
Thanks. Bob RMo8235376@aol.com