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HP Envy Laptop Power Adapter Repaired
Two days ago I got a phone call from the nephew of a good friend asking my help. It was about his HP Envy 17 n-010nb laptop. Apparently he previously had brought his laptop to a repair shop, and there they told him afterwards that his – still quite expensive – HP laptop couldn’t be repaired because of an internal short-circuit on its mainboard.
After I started examining the original HP laptop power adapter – also quite expensive at about a price of 120 euro bought new – I noticed the half broken of power cord. These laptop adapters are designed especially with a 3 wire power cord that communicates with the laptop it was sold with to check if the right original adapter is attached.
In this case the adapter gives up to a current of 6.15A at 19.5V DC. Which makes it possible to use and to charge the large laptop at the same time.
When the laptop notices that a different or for instance a universal adapter is used, or a type with only a 2 wire DC power cord, this will prevent the Battery pack from correctly being charged, or even recognized. The third DC power cord wire to the laptop power input is for communication with the laptop mainboard. This also assures the mainboard that the battery is charged correctly by the right original power adapter. It also makes sure that the battery pack is charged in the correct time it was designed for. Safety above all to prevent fire or explosions. I checked if the laptop worked with the
adapter attached but nothing happened. Which looks like a dead laptop with a mainboard failure. I noticed that the 19.5V DC voltage disappeared after I had attached it to the HP Envy 17 laptop. So this could mean that the laptop was short circuiting like the repair shop had stated. But that is hard to tell without any Led on the adapter outside. I of course first had fixed the damaged 3 wire power output cord to be sure that would give no problem. But still the laptop kept completely silence. And because I heard some crackling noises inside the 120 Watt power adapter when I attached it to the laptop I decided to start opening the laptop to check the mainboard and power jack. To my surprise there was no short circuit or malfunction at all! Strangely only a not attached power cable to the mainboard input connector. And I attached it back to the connector where it should have been attached all along. And the only conclusion left was that it must be the power adapter that was defect. So it was time to open the original 120Watt 6.15A 19.5V HP adapter and check the inside. With a screwdriver I opened the glued together plastic by giving it some blows all around the housing so both halves came almost completely loose. And by giving it some opening space I was able to take the power board out to one side (it doesn’t have to be opened all around to be able to do that) for inspection. But first thing I did was to make sure that the laptop would work when I attached an external 19V DC voltage from another power supply attached to the output wires of the now open original power supply on its 3 wire DC output cord without using the adapter itself.
And indeed the HP Envy 17 worked! Which proved that the repair shop was in error and not worth the 75 euro they were paid ! Above photo shows the adapter solder side after both Aluminium metal safety shields were removed. And by using my nose I was able to track the position of the faulty component. It was the primary interferences preventing AC input coil that apparently got hot and made the adapter useless when it failed making contact to the D10XB60 greatz diode bridge.
It only worked okay incidentally when the coil did make good contact which explained the crackling noises I heard. And so it had nothing to do with any short circuit in the laptop!
Previous photo showed the coil after my repair. Which involved fixing the two broken input wires. Next follow 2 photos that show where the coil detached itself from the solder side.
Following photos show more of the inside of the now good as new repaired 120 Watt HP adapter.
After repair both adapter AND laptop work splendidly again! And following photos are proof of that. The nephew of my friend is very happy I could help him although he previously already had bought a universal Power adapter from manufacturer Trust (that didn’t correctly charge nor recognized his original HP laptop battery pack, which could be bad too?). Also stores do not have such expensive adapters to sell in stock. So my friend’s nephew now only has to check with the now fixed adapter and another new battery if everything is working as is to be expected.
I doubt if the repair shop was qualified enough after these conclusions.
And I hardly dare to repeat myself like frequently before but again this repair is another one at no component cost whatsoever. It only took a lot of time to open and close adapter and laptop afterwards. But it was all worth it. I even may be able to fix his laptop battery but that all depends if he will be able to buy a new one for a reasonable price. And next 2 photos show the snaps I made of the controller chip on the power adapter board after I had scraped of some of the white stuff. I had to play with the contrast/brightness enhancing a bit to make the chip’s markings better readable.
I almost wanted to order a couple of these DAP 019D controller chips through Aliexpress (see next picture) but luckily there was no need for. Also because all other board’s semiconductors, with also at least one 600 Volt (RDS on of 0.24 ohm) n-channel P14NK60ZFP mosfet, checked out fine!
And next photo shows the (3 contacts) Power plug that goes into the laptop’s power input jack.
The plug outside diameter is only about 4.48 mm and none of my universal laptop adapters had this same matching plug. And neither did I have another identical HP adapter to test the HP Envy 17,3 inch laptop with. But not that I really needed one in the end.
So if you ever get a defect high power 120 Watt HP laptop 6.15Amps adapter (with likely only one year of warranty ?) you know what to do and look for.
You all have a very good day!!
Albert van Bemmelen, Weert, The Netherlands.
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Note: You can read his previous repair article in the below link: