Way To Solve Sony Mini Hi Fi Push Power Protect Problem

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:

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

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:

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

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

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

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

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.