When i switch on it will appear protection and goes off

SD cards have a slide switch along one edge. The position farthest from the metal contacts locks the card, protecting it from writes. The position nearest the contacts unlocks the card.

A short has transpired before the fuse. Now in protect mode. See a tech.

The power supply regulator section circuit has to be troubleshooted. There might be some shorted component/s. It is a skilled work. You must have sound knoledge in electronics to do this work.

These digital amps are very prone to blow if the speaker wires are shorted so Sony appear to have put in a protection system that mutes the amp when this happens. You have to unplug the amp for a minute till the light goes off, make sure no speaker wires are touching each other and then it should work ok. I found the same problem with one I bought 2nd hand.

Audio receivers have an output protection circuit called "protect mode", this is to protect the receiver from short circuit failures.The speakers and speaker wires are what I inspect thoroughly first, look for bare speaker wires,or bare wires that are touching each other at that point,check speaker wires at the back of the receiver for sloppy connections,etc.If all looks good then try disconnecting all the speakers at the receiver,then turn power on to see if it goes into "protect mode", if it does the the receiver probably has an internal short and will need to be sent in for service,if it doesn't go into "protect mode" then connect one speaker at a time back into the receiver until it does go into "protect mode" then which ever speaker you connected last is the speaker that is shorted(blown) and then you know that speaker is the problem and it will need to be replaced or repaired. Good luck !

This has happened on my receiver but it goes away if I switch it off and turn it back on again.

Disconnect all the speaker wires at the receiver and turn it back on. If itdoesn't go into protect mode, your receiver is ok.

Reconnect the speakers one at a time being sure to turn the receiver off each time you connect a speaker and turn the receiver on until your receiver goes into protection mode again.

When it goes into protect mode again, the last speaker you connected has a problem. Trace the speaker's wire to the speaker looking for cuts or shorts along the way.

If you have a multimeter, switch itto ohms and check the speaker for a dead short, if you show a dead short you have a blownspeaker. Hope this helps.

--Matt

If you have a USB memory stick that has a small slide switch on the side, this switch is a copy protection switch, move this switch to allow you to copy onto the USB memory stick.

You have an amp failure, this can be a problem with a speaker but is more often a shorted output channel.

You can check to see if it is a speaker by disconnecting the speakers and then turn it on. If it goes into protect again, you have a shorted output channel. If it turns on, you may have a bad speaker.

If it turns on, try connecting one speaker at a time until it goes back into protect. When it goes into protect, you just found your bad speaker (last one connected).

Make sure you turn it off before connecting a speaker. Then turn it back on again. Do this for every speaker you have.

If it stays in protect, you should take it in for service. Unless you have the proper tools and experience working on electronics there is nothing you can do to repair this yourself. I have seen many people try who were not qualified to work on electronics, and more often than not, they cause more damage than they started with which results in a more costly repair.

Let me know if you need any more help.

Dave

'Protected' usually appears on amps or combined cd/amp units when the main processor detects a short circuit in the speaker connections and the unit goes into 'protect' mode to stop further damage.Check the speaker connections. You may then need to reset the unit by holding the power switch in for a few seconds while powering on the mains cord for example. Sony A/V amps are notorious for this issue.