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How To Repair No Power Problem In Hi-Fi

By on February 15, 2017
how to repair no power in hifi system











My customer sent to me the OLAN Hi-Fi system with the complaint of no power. As usual, one has to open up the casing in order to check on the power supply board.

Once the cover was removed I could see there were few sections such as power supply board, DVD board, DVD Tray system and etc.

hifi circuit board

The first thing I checked was the power supply board because the complaint was no power. If the complaint is can’t read DVD and etc, i would check on the DVD tray system area first.

how to fix hi fi

Upon visual inspection, I saw that the main fuse was slightly dark and it was blown-see the photo below:

how to repair hi fi no power

Further checking I found the power IC was burnt and exploded. The part number is HBS6838.

how to repair hifi

From experience, once the IC is blown , it could also kill other surrounding components. Thus I had to check all the surrounding components (photo below). If you would like to learn how to check electronic components you can get Jestine Yong’s ebook HERE.

how to check hifi no power

After spending some times, I was surprised that there was no other bad components so I concluded that it was only the main fuse and the power IC that were defective.

burnt ic

hbs6838 ic

Once the power IC is fixed, I connected a light bulb in series with the fuse line and powered On. It was a good sign that the bulb did not continuous light up. All the output voltages were measured good.

fixing hifi no power

After the replacement of the two components, I powered up the Hi-Fi and see the result below:

how to fix no power in hifi system

The power came back and I was very happy that another equipment can be saved from the dump. By the way if you would like to be a pro in switch mode power supplies repair, you can check out Jestine’s ebook HERE. It has the step by step guide and tons of photos to remove all the guesswork which includes the light bulb testing method in repairing switch mode power supplies.

Happy Repairing!


This article was prepared for you by Suranga Bandara who owns an Electronics repair shop in Anuradapura, Sri Lanka.

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Note: You may check out previous post about fixing active speaker in the below link:




  1. Parasuraman S

    February 15, 2017 at 10:16 am

    Good job! Thanks for sharing!

  2. Yogesh Panchal

    February 15, 2017 at 3:38 pm

    Congratulations! Suranga for quick fix.

  3. Albert van Bemmelen

    February 15, 2017 at 3:39 pm

    Not bad if only the internal Mosfet in the HBS6838 was defect Suranga! That must be between Drain pins 5,6 and GND pins 7 and 8. I couldn't download a datasheet but was able to read the specs of this controller on :

    • suraga Electronics

      February 16, 2017 at 2:43 pm

      Hi. Mr,Albert,
      Thank you So Much..

  4. Kushan

    February 15, 2017 at 5:53 pm

    A great informative article, Thanks for sharing suranga

    • suraga Electronics

      February 16, 2017 at 2:45 pm

      Hello.. Mr. Kushan.
      Ok. Thanks !

  5. Luciano Khware

    February 15, 2017 at 7:38 pm

    Another successful story. Keep it up!

  6. moniem

    February 16, 2017 at 11:56 pm

    Good job thanks for sharing information

  7. Sunday

    August 10, 2017 at 1:26 pm

    Please, can 100watt bulb be use instead of 40watt lighting bulb, and can we replace power ic no- 7N65C with 7N60F will it work, Thank.


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