Power Connector

A common weak spot on most laptops is the DC power jack. If someone trips on the wire while you have the power adaptor plugged into your laptop, chances are that the power jack will get damaged.

Dislodged pinOn most laptops the DC power jack is soldered directly to the motherboard and there are only three or four small pins holding it in place. Unfortunately that makes the power jack quite weak. Any sideways pulling of the DC power cord while attached to the laptop will usually dislodge at least one of these pins, breaking the solder around it. Modern laptops use quite a lot of power, from about 70W to 120W or even more. The bad electrical connection from the dislodged pin will cause sparks and heating that will eventually burn a hole through the motherboard and can even be a fire hazard. The usual signs of that are:

  • The battery is not charging properly or stays at half charge despite that you have been using the power adaptor.
  • The screen flickers (the brightness is changing) while the power cord is plugged in. This is caused by the laptop switching between DC power (screen is brighter) and battery power (screen is dimmer).
  • The DC plug gets hot after a few minutes of use and may even smell of burning.
  • There are “scratching” sounds coming from the DC jack.

All of these symptoms are caused by poor contact between the DC power jack and the motherboard.

There are several models of laptops that are resistant to this problem. All older Dell laptops that use the three pin DC power jack are usually not affected, probably because the power cord pops out easier. Also some older Sony Vaio models, and 1-2 Toshiba models where the DC jack is attached to the case away from the motherboard and all new Apple laptops, where the DC power cord is magnetically attached to prevent any damage to the laptop if someone trips on it.

To test for broken power jack:

  1. Remove the battery
  2. Plug in the power cord
  3. Start the laptop
  4. Gently wiggle the DC power plug on the back of the laptop

If your laptop shuts down abruptly (looses power), find a repair shop that can resolder or change the DC power jack as soon as possible, as the motherboard has already started to burn around the dislodged pins. Some repair shops will offer to replace the whole motherboard, however the price of a new motherboard together with the labour charge for installing it will usually be greater than the current value of your laptop and can go well over a thousand dollars.

Fully disassembledReplacing or re-soldering the DC power jack is not an easy job too. It usually takes two to three hours depending on the damage and the model of the laptop. To reach the power jack, the laptop has to be completely disassembled and the motherboard taken out. Then if the board around the dislodged pin is badly burned, the power jack has to be un-soldered and the board has to be patched. After that a different power jack has to be installed, attached to the case of the laptop and connected with wires to the motherboard, as the patched board wouldn’t be strong enough to support the original type of power jack that was soldered directly to the board.

99 thoughts on “Power Connector”

  1. Thanks for the fabolous informations.

    I had triped by inserting in my notebook (asus f3jc) a power adaptor of another laptop a few months ago.

    The pc immadiately shutted down. After having turned on it, it functioned perfectly, but from that day the battery doesn’t function. The computer doesn’t reveal it and the power adaptor doesn’t recharge it.

    Could you help me? It should be the DC power jack that is to be replaced?

    I tried the test you suggest, by gently wiggle the DC power plug on the back of the laptop, but nothing happened.

    If it is not the DC power jack what it should be? When I inserted the power in the jack, what it should be burnt on the motherboard?

    Thank you so much for your help.
    Regards

  2. i have all those syntomps you listed above. But i d’n know wether it affected my motherboard. How do i test such that i will give up it th motherboard is fulty. THANKs

  3. i have dell inspiron1525 laptop when i connect adapter then aftersometime my left side screen become dark when i remove adapter aftersometimes its good mean if supply through battery then ok what is the problem,plz solve my problem.

  4. Hi guys I have a hp G7000 laptop the power adaptors wires was exposed and it touched each other wile pluged in and laptop just died I bort a new adaptor but still the same thing don’t want to go on any help on what it could be please guy

  5. Hi guys I have a hp G7000 laptop the power adaptors wire was exposed and the two wires touched each other it probably affected my motherboard cause I bort a other charger but it still don’t want to go on can you guys please give me advice and thanx in advance really apriciate it alot

  6. Dell Inspiron 10 mini…had the same problem as #45. I replaced the motherboard and the on switch and it works fine. Hardly ever used it..but read there were similar problems with the mini’s. Good thing, the two parts weren’t too expensive on ebay.

  7. hi i have a dell inspiron N5010 and a dell inspiron M5040 and my problem at the minute is that both laptops say that they are charging but not taking a charge?? Ive tried swapping the batteries and ive got 2 power adaptors and tried both of them in each laptop and the same is happening is it possible that both laptops or power cables have the same problem or is it a problem with the motherboard if anyone can help id greatly appreciate it.

  8. Very useful information, I have a toshiba and the power jack need to be replaced. I was wondering if there is a cable to power the laptop from the pin battery connector. Thank you for sharing!

  9. I having trouble with my dell inspiron mini 10 it doesnt want to charge it turn on with the charger. And I also wanted to know if a Compaq charger will it work instead of the original charger because the original charger seems to not be working for so would it work instead of it and if it isn’t that what else would it be wrong because I put a power checker and it seems like there’s power going to the laptop but doesn’t want to turn on so what would be would you please get back to me on it soon as you can thank you and have a great day

  10. when i plug in adopter to my laptop its mouse stop working after some time, when i plug out adopter mouse start working what is solution of this problem.

  11. I accidently plugged my external hd power adapter in to my laptop’s ps/2 mouse port. Now the only way I can power my laptop is with both the external drive power adapter and the laptop power adapter. Any ideas?

  12. Is anyone aware of commercially available DC power cables that can connect directly to the connector that the battery normally connects to, thereby not requiring repair of the non fuctional DC jack ?

  13. The power cable indicator shows it working find, but then it started showing not charging on the laptop I wiggle it and it works and then one day as plugged the cable into the laptop, I smell a burnt and a smoke at the back of the laptop where plugged the cable since the laptop want power up. please tell me what the problem could be and what to do to solve it

  14. Well i had similar problem, whit an old hp-compaq nx9010 motherboard dc connector jack, whit a de-soldered in few junctions , i open it removed the jack, clean the board whit 66% anti-septic alcool, “rash” a bit the conection point to gain few “grip” to the new soldering material, fixed a bit the oldjack whit melted plastic that i did whit soldering-iron,puted back the jack on place,worked whit cold iron material and after i heated up , wen i started the laptop hp-compaq nx9010 it was like new!!
    Just to prevent that the jack would givehim selft a lack ,i have filled the sides and top so the case could make pressour on the jack.
    Also adapted 2 wireless antenas in lcd frame and a wireless adapter,trade also a new 15″ lcd screen from a dell p-70 or so,all worked just fine.
    Now my problem is to adapt a acer 1690 14.8V/4.400Mhl, to the hp-compaq nx9010 laptopseries that also uses a 14.8V/4.400Mhl batery…..i have the datasheet for the acer battery, description for each pin, now im having dificulty to find the hp-compaq nx9010 motherboard pinout description…
    can any one help on this one since this guy HAS A GREAT WEBSITE IN THIS AREA!

  15. Can anyone tell me what is the purpose of the boot on a dc powerjack harness? I’m replacing a harness on a toshiba laptop, but with the new harness, the boot is at the jack side, and it was on the motherboard side on the old harness. The boot makes it impossible for me to put the top cover back on my laptop. I see that under the boot is a plastic piece with the wires wrapped around it a time or two. What does that piece do? If I removed that piece, would that damage my laptop? It makes me think that it has something to do with regulating the power going into the motherboard? I have seen pictures of other harnesses, and with some models of laptops, they don’t have the boot. Any help? Thanks, Ron.

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