Question about Sony STR-DE475 Receiver

2 Answers

STR-DE475 receiver flashes "PROTECT" when turned on

My Sony receiver was working fine last night. I have it hooked up to (4) speakers plus a sub-woofer. When it was turned on this morning it flashes "protect" on the display. I have a Vizio flat screen TV,DVD player,CD player and cassette deck all Sony products hooked up to it.

Posted by mllrmarvin35 on

  • dhuang1205 Apr 07, 2009

    It comes on 5 seconds after power-on.  I don't have anything connected to it.

×

Ad

2 Answers

Anonymous

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

  • Master
  • 8,546 Answers

Protection is usually a sign of overheating or something is wrong at the power amplifier's output.

Theory: Protection is a delay and sometimes an internal test to allow the electronics to stabilize during power up before they are allowed to interact with the speakers. The most common cause of it remaining ON is that a speaker cable pair is shorted. Some isolation is required...

1. Turn the Power OFF.
2. Disconnect each set of the speaker wires that are directly attached to the receiver. Mark them so you remember where each one went. pay special attention to which conductor is on "+" or "POS" and which is on "-", "COM" or "Ground". You may elect to disconnect them one pair at a time if your sytem is complex and you don't want to lose track of where things were.

Turn the Power ON. Is the "Protect" indication gone from the display?
--------------------
If YES, you have a shorted speaker wire or speaker. To isolate the specific cause:

1. Turn the Power OFF.
2. Attach ONE speaker wire pair at a time and test it by turning the Receiver ON. When the "Protect" light returns you have isolated at least one of the cause(s). Disconnect the defective speaker cable and continue isolation of all speaker cables. Visually examine the cable at both ends for frayed wires that could touch each other or contact metal on the receiver or other objects.

To isolate further within the cable/speaker pair - disconnect the speaker end of the cable on the failing path. Try another cable that you know works, or at least one that doesn't cause Protection to stay on.

If you're electrically savvy and have a Digital Volt/Ohm Meter you can troubleshoot the short(s) with it.
-------------------------

If NO, there is probably an internal problem.

Is it solid or does it come on after the Receiver has been ON awhile.
It could be overheating.
Is the unit hot to the touch?
Is there a cooling device (fan)?
Is it stopped or clogged with dust?
Is there adequate ventilation around the unit for air to flow?
Clean any ventilation slots on the top and bottom of the unit.
Avoid stacking components that produce heat under an amplifier or receiver. Their heat rises. Also keep them away from other heat sources like like home heating vents and radiators.

Problem solid and NOT related to the speakers or heat: internal malfunction.

Let me know.

Posted on Apr 02, 2009

Ad

Anonymous

  • Level 1:

    An expert who has achieved level 1.

    Problem Solver:

    An expert who has answered 5 questions.

  • Contributor
  • 3 Answers

Could it be the internal fuse

Posted on Oct 16, 2009

  • Anonymous Oct 16, 2009

    you have just scammed my money and gave me nothing idont already know.experts ,idiots more like

×

Ad

Add Your Answer

×

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

0helpful
1answer

Helo ! I need to know why the subwoofer is silent when I connect it to my receiver-STR DE 475 . Plus , the sorround does not work . When I push the bottons , I either get the centre with the front...

Have you looked at the manual? There are procedures for adding a sub (which is NOT necessarily assumed to be there) and assigning bass to it.

http://www.retrevo.com/support/Sony-STR-DE475-Receivers-manual/id/387bh949/t/2/

Then there's the unidentified sub's manual and requirements to consider.
0helpful
1answer

Sony str de 475 ?? is appear 'protect' on screenboard and can not listen anything

The message appears usually when the wiring is wrong (short circuit) or the speakers are defective or their impedance is too small for the amplifier's output (for instance 4 ohms speaker connected to an 16 ohms output). First, check your connections.
0helpful
1answer

Sony STR-DE475 receiver ''protect'' problem

The relay or relays that click disconnect the receiver from the speaker terminals so that no dc voltage can burn out the speakers. More than likely the power output transistor(s) are faulty. Look at the relay(s), determine the input and output connections. The inputs come from the output power transistor and emitter resistors area, the output of the relay(s) connect to the speaker terminals. Check for dc voltage on the input contacts in the range of 30-60 volts possibly. If dc voltage is found there then you have bad outputs, caps or emitter resistors. A word of caution -troubleshooting at this level requires advance knowlege of electronics, do not attempt this with out onsite help from a experience tech.
4helpful
2answers

Right front channel not working

try to check balance adjustment if working.
0helpful
1answer

No subwoofer

Make sure you have sub pluged into the sub pre out and not the six channel input.

CABLE GUY.
0helpful
1answer

How do i disable the protect mode?

Ensure your speaker ratings (4 ohm, 8 ohm, etc) are sufficient with the output of your unit. The protect mode sense a currently level on the output amps that is nearing the failure rating. Just make sure your have properly rated speakers.


2helpful
1answer

Hook up wireless speakers

I'm assuming the wireless speakers you have utilize an RCA jack to connect to the receiver.

Solution:

The good news is yes, you can use them on your receiver. The bad news is that the only output on your receiver is "VIDEO OUT" so whatever you want to watch or hear on the wireless speakers must be connected to the "VIDEO INPUT".

If the wireless speaker module uses speaker wire to connect to a receiver you will simply tap into the surround thumb clip speaker jacks.

I will add that wireless speakers tend to be disappointing when used in home theater.
1helpful
1answer

No sound from rear speakers during test tone usng Sony STR-DE475

I had this problem last night.

To solve it, you can reset the amp by:

1) Put the receiver on stand-by
2) Hold down "MODE" button and press on button
3) "S.F. CLR" appears in the display and surround is back on.


Good luck

Dr Gardner
0helpful
1answer

Surrond Sound Rear spaeakers

yeh i get the same problem.. i have 5 speakers hooked up to my str- de475 and cannot get sound from my sl/sr speakers its a nightmare aint it? why is there no soloutions on the net for?
Not finding what you are looking for?
Sony STR-DE475 Receiver Logo

1,536 views

Ask a Question

Usually answered in minutes!

Top Sony Audio Players & Recorders Experts

 Grubhead
Grubhead

Level 3 Expert

5720 Answers

The Knight
The Knight

Level 3 Expert

76823 Answers

 Francisco Mauricio...
Francisco Mauricio...

Level 3 Expert

1551 Answers

Are you a Sony Audio Player and Recorder Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...