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.

90 thoughts on “Power Connector”

  1. The first time my laptop screen started flickering and showing horizontal lines I took it to a repair shop who replaced the DC plug and fixed the problem. It flickered first when it was only connected to the power then after a while all the time and especially when opening videos or using Alt+Tab to switch between programs.
    The second time this happened I changed the DC plug again (costing me 50 dollars) and it worked. I also bought an external current protection which shut down power going to the charger when the outside current was too high or too low (which happens sometimes in my country).
    About a week ago the problem started occasionally appearing again (even with the current protection) especially when the laptop was hot. When I closed all running programs sometimes the flickering stopped. When I ran the laptop for a lot of time it starts happening.
    Now I think I’m going to take it to the repair shop again who advised me that if the problem persisted I should probably buy a new laptop because this one is “broken” from its core. It lasted several month between each repair and reappearance of problem.
    This article is the first one I came across that offers a good potential explanation of the problem. I just hope my motherboard isn’t hit.

  2. Hi, I removed the battery from the laptop and plug the charging point to the laptop. there is no any disturbance in laptop operating but the port is still hot as burning fire. I also gently wiggle to the plug but no any disturbance like switch off laptop or scratching sound in speakers. why this is happen so please give me response about it.

  3. Hi, my daughter tripped over here power cable and the internal cable that connects the plug (that takes the external DC jack) to the PCB board broke off one of the terminals of the plug. The other end of the cable has a PCB connector that can easily be disconnected from the motherboard to remove the whole cable assembly. Now I need a replacement plug-cable-connector assembly. It is a Dell Inspiron 13, 7000 series. Where can I get this? I have a picture.

  4. Hi, i have a smasung R510 laptop. Ive just got 2 new batteries for laptop & when I unplug after charging the laptop recharges it self. Then I have to plug it in & it says its plugged in but not charging (at 75%). It also loses charge very fast (about 1% a min approx) when not plugged in…what can be causing this please?

    Can you email me with help to: lady…

  5. samsung chromebook XE 500 C 21 H01US
    port charger was loose , so I trued soldering. now wont turn on.
    did i use too much solder?

  6. Working on Leptop when I attach charging pin in my Leptop after few minutes my leptop goes to switch off. Kindly tell me someone how to solve this problem

  7. Yesterday when I was using the Lenovo G50-70 which is showing me 7% battery level, wrongly inserted charging plug into USB type C port,and it suddenly went off now its not showing any display on the screen,no LED lights are getting on and also power button is not working,what may be the problem.

  8. I am using dell vostro. When we connect the charger in the laptop suddenly power gone and in few minutes it resumes.
    Same has been in the removing charger also.

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