Little Known Way To Solve Sony Mini Hi Fi Push Power Protect Problem

By on February 2, 2016
stk442-130 ic








stk442-130 ic  repair

The complaint of this Sony HCD-RV6 Mini Hi-Fi was once you turned it On, you can see the message “Push Power Protect”. If you search from the Internet, it seems that lots of people are searching for the solution.

It can be caused by shorted wires in the audio speaker, shorted speaker, power related problem and bad Class AB 2 Channels AF Power Amplifier IC. As usual, in order to see the circuit board, one has to remove the back cover first-see the photo bellow:


sony push power protect repair

You also need to remove the tray before  you can pull out the circuit board.

sony push power protect repair hi fi tray


From many previous repair case histories, the major cause of the Sony Push Power Protect Problem were due to the bad Class AB 2 Channels AF Power Amplifier IC and the part number was STK442-130-see the photo below:

sony push power protect repair stk442-130

sony hi fi repair

Besides the IC, I also found 2 pieces of 100 Ohm resistors had an opened circuit and two 22uf 100 volt were bulged.

sony push power protect repair stk442-130 ic



I had to buy a new IC for replacement and for the other parts I had them in my spare parts compartment.
stk442-130 ic replacement


Here is the STK442-130 IC schematic (hard to find datasheet) for you to refer.

stk442-130 datasheet

Once the parts had been replaced and powered On, look at the result below:

sony hcd-rv6 push power protect repair

Conclusion- The Sony hi fi push power protect problem seems to be very common in quite a number of models. What you need to do first is to check and make sure the output voltages from the power supply are good and no shorted audio speaker wires. If these checked to be good then you need to go straight to the amplifier IC section. Don’t straight away replace the IC and retest because sometimes corresponding components also can be the cause of the problem. All the best to you.









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

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Note: You may check out his previous repair article in the below link:




  1. Albert Hoekman

    February 2, 2016 at 5:52 pm

    Thanks for sharing the article, nice job!

  2. Albert van Bemmelen

    February 2, 2016 at 6:19 pm

    Thanks for another nice Professional repair. Sony like Packard Bell and many others make devices for the Consumer Market at Home that often seem to be dropped into the Stores even before they apparently are thorougly tested. Which won't do them any good in the long run. The result is bad publicity all over the Internet by unsatisfied customers who will buy their next product from other Manufacturer's. Therefore it is a good idea not to buy any new product but to wait and afterwards buy any older product that earned its value. Recently I bought a second hand HDD/DVD recorder, and a used perfectly working Printer/copier on Marktplaats (Dutch daughter of Ebay?). And I know the devices are cheap and well produced!

  3. Tito Kanshulu

    February 2, 2016 at 7:15 pm

    Thanks for sharing the information Suranga. Your explaination is quite comprehensive. I also,happened to come across a similar problem but the only culprit was a bulged capacitor.

  4. Robert Calk

    February 2, 2016 at 9:06 pm

    Nice job, Suranga. Thanks.

  5. Parasuraman S

    February 2, 2016 at 10:11 pm

    Good Job!

  6. Mark

    February 3, 2016 at 7:05 am

    Hey Suranga,
    Thanks for a well written article and diagnostic path.
    I have been working on a Panasonic SA-HE70 Amp which comes up with a F70 code. It usually is a power issue at fuses etc, but mine has had other issues, including dry solder joints and faulty power amplifier. At the moment it is sitting on my workbench, just staring at me, taunting me, but as my confidence grows with my skills, I will tackle it again. I have a full schematic for it, which is a help, but for now time is a factor.
    One day......

  7. gene

    February 5, 2016 at 12:49 am

    great article

  8. Reychie canonigo

    February 7, 2016 at 6:30 am

    Nice job sir

  9. Manoj

    July 26, 2016 at 3:02 am


  10. NEGLAY

    October 25, 2016 at 10:57 pm


  11. karim metwally

    November 9, 2016 at 11:50 pm

    Is there is any solution to fix the ic by reprogramming it by somekind of external kit

  12. Tesfaye kebede

    February 16, 2017 at 11:46 pm

    Thanks suranga a well written article

  13. asanda

    April 7, 2017 at 11:09 pm

    My sony MHC-RG22 has display the protect push power what can be the cause?

  14. reychie canonigo

    June 19, 2017 at 3:32 pm

    wow yo are awesome.

  15. ahmed

    July 10, 2017 at 3:31 am

    hi i need some help about a no sound from my mhc rv5 when i power up it display " C81 " excuse my bad english email me any solution
    Receive my cordial greetings from algeria

  16. Priyadarshi Dutt

    September 8, 2017 at 1:41 am

    Hi Suranga,
    Great article especially thanks for the supporting pics you posted.
    I have Sony MHC V40. Its display stopped working long back. I was using this system by connecting mobile using aux cable to enjoy music under MD/Video option.
    Recently sound also stopped working. And no response to remote also. Only power switch is working.
    My friend said that it must have went into protect mode.
    What can be the possible cause?
    Changing STK402-100s ic will solve the issue?
    Both display and sound..what else can be the cause..
    Please help.
    I badly want to make it functional..

    One additional info.. Sometime back while playing song at louder volume suddenly disturbing sound could be heard..
    I found out that speaker coil was partially broken near the joint at connection to frame..and spark in that damaged part produced that disturbing sound. That speaker I'll get fixed..

    But the system needs to be fixed.
    Kindly help me fix this issue..
    Thanks in advance..

  17. micheal

    October 10, 2017 at 7:54 am

    my keyboard Yamaha displays the program but there is no sound, what could be the problem?

  18. Rotex

    January 11, 2018 at 8:01 pm

    Please, can a bad STK IC cause the unit not to power on completely?

  19. Ndumbehson

    March 1, 2018 at 8:58 pm

    I removed the capacitor and put a new one but the problem is still there. So I am looking for the intergrated circuit STK 422-130 so I can replace it. Hope it works

  20. Jeffy Mathew

    March 3, 2018 at 3:24 pm

    Where can I can buy The IC for this. It is not available here in kerala


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