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A dead Dell laptop charger repaired. Model: DA90PS2-00

By on September 28, 2013

A computer technician brought this dell laptop charger to my shop and told me that the cable needed to be changed. Once I opened it and replaced the cable with a brand new one, it did not bring the laptop charger back to life.


The way to open such a charger is to use a sharp knife and cut it open. When you are done, just put it back with a tiny drop of super glue on the four corners of it. Just make sure you do a nice straight clean cut so when you put it back, you will not see any gab between the two boxes sides.


I plugged in power and started doing voltage testing. There was no voltage reading at the main power capacitor and the logic way here is to start testing it from this point back to the main power outlet.

The next step to test was the voltage at the main bridge rectifier and there was no reading there either. I tested the fuse and it was not open but the moment I tested the coil that feeds power into the bridge rectifier, one of the legs was broken and that was the main power problem in this laptop charger.


As you can see in the photo, I took it out and tested it. It was broken and needed to be replaced.


Well, I looked around in my shop and could not find a new one to replace the broken one. Here is what I did. As you can see in the photo, there is some glue holding all the four legs together. I took some part of the glue that was holding the broken leg and took it out. That made the broken leg loose. I winded that wire backwards and that gave me enough wire to put back on the charge board and soldered it.

Before soldering it back on board, make sure you scratch the end of that wire so it will become conductive to electricity. You can do that with a sharp knife. Once I did that and soldered back on board, the laptop charge came back to life.

I tried it on the laptop and it worked nicely. Mission accomplished.





This article was prepared for you by Waleed Rishmawi, one of our ‘Master Authors’ and currently working in the Bethlehem area of Palestine repairing electrical and electronic equipment. Please give a support by clicking  on the social buttons below. Your feedback on the post is welcome. Please leave it in the comments.

By the way if you have any good repair article that you want me to publish in this blog please do contact me HERE.



  1. Bradley

    September 28, 2013 at 11:26 pm

    Good repair article. I have also repaired items this way.
    Good for Waleed for sharing.

  2. wael

    September 28, 2013 at 11:53 pm

    OH YES i have seen this failure in many laptop charger
    like hp which is basically so similiar to dell chargers and toshiba other 2 more common failures are shorted cable that will activate ocp and prevent the charger from producing power and open cable is also common

  3. frankz

    September 29, 2013 at 12:27 am

    Justine , I have used several of your tips to repair P C Monitors laptops and LCD televisions. Since I am still gainfully employed at 78 yrs old I u8sually only charge clients for what parts cost me. I have many people that are willing to help me with any needs i may have. Thank you for your help. frankz

    • Jestine Yong

      September 29, 2013 at 8:37 am

      HI Franz,

      You are welcome. Hats off to you even at this age you still active in electronics repair.


  4. Glicerio

    September 29, 2013 at 12:38 am

    Hi Jestine:
    Thank you for the info indubitable that is a good one.

    • Jestine Yong

      September 29, 2013 at 8:31 am

      HI Glicero,

      You are welcome and also special thanks to Waleed for contributing the article.


  5. Gary Gemmell

    September 29, 2013 at 12:58 am

    Nice fix there and good description for beginners to electrical repairs!!!


  6. Andre Gopee

    September 29, 2013 at 1:21 am

    Great article. I like to read these type or repair article where someone really do some detective work to find the source of the problem.Keep those article coming.


  7. Surjit Singh

    September 29, 2013 at 1:51 am

    Dear Sir,
    I read this article,i like this

  8. ramy

    September 29, 2013 at 2:45 am

    good , and we need your experience in laptop motherboard.

  9. Chirag Varma

    September 29, 2013 at 2:49 am

    Good Job Waleed

  10. raymundo saura

    September 29, 2013 at 9:58 am

    thanks for this article. I will help me a lot in my future repair if and when i will encounter this kind of repair.

    thanks and GOD bless

  11. Robert

    September 29, 2013 at 12:40 pm

    Great article, Waleed. I have not opened a wall charger yet but I do look forward to it.
    Hello Mr. Yong. My camera takes lousy close-up pictures so I'm hoping to get a good camera next week so I can send you the article on the anomaly I found in the 555 IC.

    • Jestine Yong

      September 29, 2013 at 5:02 pm

      HI Robert,

      Ok noted. Thanks.


  12. gaudenio valdez

    September 29, 2013 at 1:18 pm

    thank you.

  13. clavour

    September 29, 2013 at 2:19 pm

    Really good job man

  14. milo

    September 29, 2013 at 3:01 pm

    How about the rectifier and the Power Regulator? Still Good?

    • Waleed Rishmawi

      September 29, 2013 at 9:05 pm

      yes Milo, the rectifier and the power mos N fet, are good. only the coil that had problems.

  15. Amitava Roy

    September 29, 2013 at 6:17 pm

    Respected Sir,

    Waiting for a Chip Level Computer Motherboard or Laptop Motherboard tutorial as you are usually publishing in your Blog?

    Prepare it at your best so that thousand technicians can be benefited out of your as usual best effort?

  16. Kris Padayachy

    September 29, 2013 at 6:46 pm

    Dear Jestine, thanks for the devotion you show in finding solutions to these numerous daily challenges...Congratulations & blessings for your website & also for inviting other technicians to share their experience with you & all our friends out there. I thank everyone for kindly sharing valuable info on repair techniques.
    Keep it up !
    Kind regards,


    • Jestine Yong

      September 29, 2013 at 9:27 pm

      HI Kris,

      You are welcome!


  17. Robert

    September 29, 2013 at 7:28 pm

    Thank you Waleed for this. I am encouraged to look for cable faults and to at least look at laptop power supply. Could you please explain more in your next lesson where to cut open the case? Do I follow a join?

    • Waleed Rishmawi

      October 1, 2013 at 3:29 pm

      yes Robert, just follow the joint. there a nice good way of opening it suggested by Robbe. check it out.

  18. Waleed Rishmawi

    September 29, 2013 at 9:04 pm

    thanks to all the nice and the ecouraging comments. God bless you all.

  19. corriete

    September 29, 2013 at 11:25 pm

    Mr Waleed thanks so much. i have applied this method to all kinds of transformers too. Continue to share your expertise. great job

  20. Robbe

    September 30, 2013 at 12:35 am

    The easiest way to open a laptop power supply without damaging it is
    I keep it in a nail polish flask and use the brush to drop a couple of
    drops in the seam
    Do this all the way around
    Wait +- 1 min, gently pry it open
    Ad gasoline if needed
    It should come off very easily
    This is the repair tip I use the most from Jestine's blog
    Provided by a subscriber about 3 years a go
    So no cutting needed Jestine 😉


    • Jestine Yong

      September 30, 2013 at 9:16 am

      Hi Robbe,
      Thanks for the tip of using the small brush.


    • Waleed Rishmawi

      September 30, 2013 at 3:05 pm

      thanks for sharing this new tip. I will give it a try the next time I open one.

    • Mark Tembo

      October 1, 2013 at 5:41 pm

      Hi Greetz,
      Thanks for this and I will try it as well. Just that I had opened one before this trick, hence using a knife!. Thanks once more as I have so many of these coming to me for repairs.

    • Thanh H. Le

      October 19, 2013 at 12:59 pm

      Thank you, Robbe. I broke one charger with knife and screwdriver tip top. Even the knife blade broke. Pity me!

      Will use this method for sure!

      With care to drop just enough gasoline, as you show.

    • Jumbe Mateyu

      October 19, 2013 at 1:28 pm

      Thank you Robbe for the tip, I have repaired a good number of laptop chargers but the first challenge has been how to open it and using knife was the only option. Now that I have learnt the gasoline tip,I say thank you Robbe. I also say thank you Jestine for providing a forum for electronic technicians to share experiences in this field I say thank you Jestine.

      • Jestine Yong

        October 19, 2013 at 3:26 pm

        HI Jumbe,

        You are welcome and special thanks to Waleed for sharing it out.


    • Robert

      January 28, 2014 at 11:04 am

      Hi Robbe. I tried your gas trick today and it worked great! I put a couple drops on it and let it set for a few minutes. Then I repeated it again with a couple drops and let it set for about 5 minutes. Then I squeezed it a little bit in my Panavise and opened it right up with a small screwdriver.
      I have a box full of good wall warts so I picked a Motorola Cell Phone charger to open and inspect. It accepts an Input of 100 - 240v AC 50/60Hz. Output is 5v DC 550mA. Actual output is 5.1v.
      I must say that I'm very impressed with the quality of the PCB and components. Instead of a Varistor, it has a 20 ohm 2w Resistor. The SMD's on back of PCB look good also with very good soldering.
      Unless the Transformer quits or many components blow, this wall wart is definitely worth repairing.
      Thanks for the "gas" tip!

  21. Tom Dunaj

    September 30, 2013 at 3:04 am

    My hats off to FrankZ when I was in business I serviced 2 senior
    complexes an did the same thing.The help you give is wonderful.

  22. Marulitua Hutabarat

    September 30, 2013 at 6:45 am

    Nice repair tips article Waleed.
    Good job.

  23. ZAK

    September 30, 2013 at 8:15 am

    Well done WALEED

  24. atul m.

    September 30, 2013 at 12:13 pm

    Good one sir.By inspiration from your work i also repaire my CCTC camera power supply.

    • Jestine Yong

      September 30, 2013 at 1:55 pm

      Hi Atul,

      Good to hear about your success.


  25. Waleed Rishmawi

    September 30, 2013 at 3:08 pm

    with all these nice comments and ecouragements, you have made my daya brighter one. thanks and God bless you all

  26. Osak Courage

    September 30, 2013 at 5:22 pm

    thank you Sir
    i love every repair article send to my email i hav repair most personal electronic from yur repair tips
    i just thank GOD i meet someone like you
    there is a question i want to ask am a student study electrical/electronic engineering i hav a person laptop toshiba i discover that without the battery inserted i connected my charger to the pc and switch it on but getn to the login stage the voltage will drop and my pc will go off
    i check my laptop volt rating it was given DC=15v ,5A but
    the charger rating where 19v ,3.5A
    is the charger amp too small for the laptop to power on to use ? so i can get 5A charger for my laptop

    • Waleed Rishmawi

      September 30, 2013 at 9:24 pm

      I would recommend to use the orginal value of the laptop. 15 volts, 5A.

  27. Humberto

    September 30, 2013 at 7:10 pm

    Hi Waleed Rishmawi, a very good article, I have seem many from you thanks to Mr. Jestine Yong. Congratulations for both.

  28. Hamouda Néjib

    September 30, 2013 at 8:59 pm

    Good idea; Good Work

  29. Mark Tembo

    September 30, 2013 at 11:13 pm

    Hi Jestine,
    I have several of these pawer packs ( the SMPS the size of an egg ) that are faulty with me. Just as I am speaking, I have also opened one with my sharp knife so that I have access to the inside of it. I have just opened it, I will try to work on it tomorrow. I am sure I should be able to what could be wrong, with the help of this article.

  30. Ram

    October 1, 2013 at 3:01 am

    This was very helpful article. Please send this type of articles with detail in future.


  31. reza

    October 2, 2013 at 12:18 pm

    hi jesting thanks for good info

  32. Albino mendez

    October 2, 2013 at 12:41 pm

    thanks sir jestine,the first thing i've done after opening my mail is looking straight to the message you've send,coz i know it's more important than anything for me.i'm only able to open my mails once a week since i leave in remote thank you so much.God bless!

    • Jestine Yong

      October 2, 2013 at 8:11 pm

      Thanks for all the support!


  33. zeeshan zamir

    October 2, 2013 at 1:12 pm

    Hi Jestine:
    Thank you for the info indubitable that is a good one.

  34. Lalit

    October 2, 2013 at 6:04 pm

    Thanks was really i am new in this field.
    But actually i can't see this type of Inductance coil problem in SMPS or Charger...Coils are rare to be faulted..thanks again

    • Robert

      October 3, 2013 at 8:49 am

      It was probably a manufacturing defect.

    • Waleed Rishmawi

      October 3, 2013 at 3:48 pm

      Lalit. yes they are rare to be faulted but it is still a fault that we have to deal with it.

  35. Jai Prakash

    October 3, 2013 at 1:40 pm

    It's very helpful Sir

  36. Vijay hadap

    October 3, 2013 at 4:07 pm

    I like both the articles and expecting lot in future

  37. Mojy

    October 5, 2013 at 2:12 am

    That's a good repair.
    Thank you for sharing it, Jestine.

  38. Nimal

    October 5, 2013 at 4:49 pm

    That is a very good tip,but I wonder how the wire can break. Thanks.

  39. emoniz

    October 6, 2013 at 10:34 am

    Nice Testing! Thanks for the hints!

  40. Tito

    October 17, 2013 at 3:09 pm

    Thanks for the repair tip, it really helps in preventing one from having to buy a new charger. I have had the the identical problem in the past with an Aspire One net book charger which I repaired. In reply to Nimal question, the wire WILL break because of small wire size,that CANNOT take the impact of the ferrite iron core when ever charger fall from table height to floor. Manufacturer need better support for coil to PC board. Thanks.

  41. Amir Mukhtar

    October 19, 2013 at 5:11 pm

    Dear Sir,
    thanks you for your nice Sharing .
    you are doing great in order to share your experiences in ERG members .

    thanks you
    Great Job
    A Student of Electronics
    Amir Mukhtar Ashrafi

  42. Jayaprakash

    October 22, 2013 at 7:25 pm

    thank u's very nice article

  43. Gurpreet

    October 26, 2013 at 3:30 pm

    Hello Jestine

    Thanks for sharing good tips in repair and also thanks to Waleed but still I am not comfortable with Desktop's BIOS section. It has confused me a lot.


  44. Joshua oloo

    February 10, 2014 at 2:33 pm

    I like the Article,It gives me tips of repairing the L/tops chargers. good work,keep it up.

  45. Leo

    July 9, 2014 at 10:47 pm

    Interesting article,
    After open the laptop charger, there are white paste like clay or something. it becomes harder. how to clean them without damage tiny components. Thanks.

  46. Wildon priddy

    January 15, 2016 at 9:25 am

    Jestine Yong. thanks for your website,it brings the electronic tech community togather to share their repair experiences. I have. Been repairing electronics since the age of 15, now at the age of 78 , I am still active in electronic repair! Again thanks for your service , Sir! Regards. Wildon Priddy CET,KA4FKU

    • Jestine Yong

      January 15, 2016 at 9:32 am

      Hi Wildon,

      You are welcome and glad to know even at this age you are still active in the electronics repair line.



  47. purmahmood

    January 30, 2017 at 9:50 pm

    thanks a lot for clear explanation.I have similar problem with my adapter unless main capacitor has voltage about 320v but one of two winding wire was broken from middle. I just connect it but still there is no output with no LED on. I wander if there is schematic or other tips


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