Amp protection mode

Generally speaking, an amp protects itself from heat, shorts, overloads and operator exuberance by refusing to turn on or stay on.

Overloads can be from excessive periods of high output or marginally low impedance loading by the speakers; and shorts would be wiring issues or a speaker blowing up.

You should be able to feel if it's hot. WHY is it overheating? Make sure it has sufficient ventilation on all sides and that vent holes are not blocked by dust balls. Ensure the fan (if equipped) is running as designed (some only operate on demand). Clean dust and debris from it.

If the amp comes back on after cooling, you're lucky. They only have so many self-protection cycles in their lives so continuously resetting or cycling their power without addressing the cause can do more harm than good.

If it protects immediately on a cool power up you should disconnect the speaker connections and try it 'naked'. If it comes up then diagnose which lead(s) are shorted. If it does not come up the problem is internal and should be left to an experienced and competent hands-on tech.

This can be an indication of protect mode. See the link below for an explanation of protect. If you have any additional questions or wich to attempt a repair yourself, please update this and I'll provide additional information.

Dan

Link: http://www.fixya.com/support/r5390728-protector_means

Yes, you can do this easily.
Perform the following steps
(1)Plug your amp to AC outlet.
(2)Switch it on.
(3)observe time taken for switching off.
(4)immediate to shut down over current protect(5)3 seconds to shut down DC protect.
If over-current protect do the
following steps
(O)unplug the amp.
(1)download NR806 service manual.
(2)open the amp metal cover.
(3)measure 7 large white resistors resistance loacated next to power transistors mounted on a large heat sink with black probe touching the middle pin and red probe to first/left or third/right pin.
(4)If this 3 Pins large white colour 0.22ohm x 2 resistor is open with infinity ohms ,
(5)replace it and jot down this channel for example left surround faulty. Usually only 1 channel went faulty.
(6)the two large power transistors next to this white resistor 0.22 ohms x2 should also be replaced.
(7)plug the amp
(8)switch it on
(9)if ok, troubleshooting get done
(10)if not ok
(11)replace ALL the components of this power amp channel.
(12)pre-amp section no need to check.

This is a short or unstable ohm load. Remove all speaker wire connections to see if the amp will stay on.
If the problem goes away when disconnecting the speaker wires try this:
1) Check volume level on zone one and zone 2 if connected. If it is too high the amp will go into protect mode and shut off exactly as you described.
2) Make sure no wires are touching any other wire or the metal surface of the amp. This will cause a short and send the amp into protect mode.

Is the red light flashing at first?
The unit may be going into protect mode. Lets hope it has done the job and the receiver has protected itself from failure.
Protect mode can result from speaker wires touching each other or the Amps metal case. Check that first.
It can also be caused by unstable ohm loads if too many speakers are connected to any of the outputs especially zone 2.
If you can remove all speaker wires and turn the unit back on. If it stays on, turn the volume down on the main zone and zone 2 if connected. Then reconnect speaker wires.

The manual suggests disconnecting inputs and outputs and power, letting it sit for an hour, then plugging it back in and turning volume to max to see if it still shuts off. If it does, the problem is with the unit. If it doesn't, the problem is elsewhere.

Judging from some other sites, this is a common problem. If you take it to a dealer, suggest they check the AC input. Before anything else, make sure that there are no stray wires on your speakers connecting the positive and negative clips, which will cause a short and activate the amp protection.

I had the same problem with an Onky502 and replaced it today with an Onkyo606. It worked fine for an hour then started shutting off automatically. I'm following the manual and letting it cool off now for an hour, and meantime I'll check my speakers.

when i connect left front speaker it's shuts down .
That is probably due to protection caused by either
DC or over current. This means your troubleshooting is not complete.
Preform these steps.
Download SR605 service manual.
(a)unplug the amp.
(b)Connect left speaker (c)remove the vertically installed pre-amp board.
See this:
How to do?
1.Unplug the amp.
2.Remove the metal cover.
3.You will see a long vertically installed pre-amp board mounted next to those large power transistors fixed by 12 screws on a large aluminium heat sink.
4.Remove this long vertically installed board mounted by 2 screws.
5.With 2 screws removed, just pulling this board out and hold it with one hand.
(d)Plug the amp and switch it on.
(e)If your amp stays ON forever, the problem is from this long board.
(f)If switch off at once, the problem is from power amp board.
Try the above- mentioned steps to confirm DC or over-
current in left channel.
(g)For DC protection, replace ALL components on left channel of the vertical board.
(h)For over-curremt protection, replace ALL components on left channel.

Replacing ALL components on a faulty channel do not cost you too much.

The output section has smoked and requires repair. The unit is not in "protect" mode. This means that the outputs are turned off to prevent additional damage to either the amp or the speakers. Expect a repair to run from $15-$40 in parts plus the local labor rate.
Dan

Psgolfer ...I pretty shure you dont need that. It just needs to be reset, its in protect mode.....hold the power button down and the A n B speaker buttons down at the same time for 30 sec.....ok , Radricktip

It is not a blown fuse. Your baby is in its ***** throes! It is fubar. You have either a damaged power supply or blown output stages (since sounds horrible it is probably this).