My Sony stereo system MHC-RV555DA is blinking Protect continuously and won't play. What's the cause and How can I overcome this problem

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protect usually means a short somewhere in the amp. This will have to be repaired before the unit will turn on.

may i see a diagram showing where the ic goes?

Your stereo went into protect mode to prevent complete failure of the amplifier inside that radio. Most of the time this happens from playing the stereo real loud for a real long time and it overheats. Most of the time disconnecting the receiver/stereo and letting it cool all the way down or at least 5 minutes and then reconnecting it to the power source will reset the protection mode. You want to make sure you are keeping the radio cool. Don't stack anything on top of it and try keeping a small fan blowing on it to expedite the heat out from the unit. Also turning it down every now and then to let everything cool down a bit will help prevent it from going into protection mode as well.

Make sure songs are in mp3 format so MHC-ZX70 can playback it

something inside the unit has become faulty electronically, otherwise if u have moved the unit with cds inside, they may be out of allignment and causing the unit to go into protect.

one of the out put tran is short ,
there normaly 4 to 8 of them
screw to a big heat sink ,
easy to get to.
check with a volt meter
then google the part
they cost 8.00-12.00

only use original speaker, check cable circuits..

The audio amplifier IC is damaged and need to be replaced

to restart, press stop, clear and display at the same time.