Protect Light Flashing.
I too have one of these with the same problem,the unit is only 3 years old . I too did the troubleshoot check on both AVR and speakers but still the same .
I was sent a sevice manual by Denon and as a result of a quick study of the circuit diagram , I tried diconnecting the jumper link to the processor which is labelled 'Protect'. The effect of this was that when the unit is turned on , the display is now visible as normal , but no sound from the speakers .
It seems that the main processor requires a very small voltage from the output of the power transisitors to trigger the main processor to operate the speaker relay circuitry , but when there is an overvoltage ( whether of an intensity harmful to speakers or not) , the 'protect' circuit is triggered and remains so.
Can anyone offer some further assistance ?
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Re: Protection Light Flashing
You will need to measure the output transistors as well as the driver transistors or IC's for shorts, as it is a DC voltage that will trigger this protection circuit. If you have a PDF of this service manual, I would like to take a look at it and to tell you what to check.
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the red flashing LED is that the Device is in protection mode.
the internal power supply . +15 volts and -15 volts are defected you need to be replace it ... Regulators 7915 and 7815 .... these you should change , might also need to check capacitors .
these are common defects for Denon . AVR units.
Hope this helps
Are you getting a standby light at all? Is it flashing? Do you here a click when you plug the unit in? If the answer is no to all of these then you blew a fuse. If you do have soome sort of standby light, then your set is in protect mode. More than likely for a blown channel. If no lights, but you ar egetting a click, you could have a bad transformer. Use a DVM and see if it is open or not. Good luck
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 unit is in protect mode. This effectively shuts off the output amplifier section. This happens because a problme is detected in the output section. This unit will require service. Most likely the output transistors have failed. Figure on $20-$40 for parts plus the local labor rate for repair cost.
Probably some speaker wires got shorted or the output stages freaked out and the cpu went into protect mode. Normally plugging it out of and in to the wall socket should/could reset it.
First check all wiring at the speaker outputs and on the speakers then if it still wont startup you could try the avr-1500 method with some trial and error pressing of buttons.
avr-1500 reset method: Unplug the unit from the wall, hold down both video select and audio
select at the same time, plug it back in. Keep holding both buttons for
2 secs, unit will reboot. As you have no audio select button on your avr-1100 you might try pressing video select and another key to see if this will reboot it.
I just picked up a non working AVR 900, there are a total of 4 fuses inside the unit: 2 on the protect board, 6.3A and 8A, and 2 in the middle near the front.
I was told by Denon the following might reset the microprocessor.
1) unplug unit
2) press and hold tuner and video select on front panel
3) plug in while holding buttons
Unit display should flash until you let go of buttons.
Unit stays on you should be ok/ goes back to red- service
They also said:
There are 3 types of protection that will commonly occur with our receivers. This is designed to protect the unit from permanent damage.
1) Thermal Protect = When the unit overheats this will occur, usually if there is not enough air space above and around the unit. There cannot be anything directly on top of the unit and there must be at least 4 inches of airspace above the unit.
2) Overload Protect = Most commonly occurs when a strand or more of copper speaker wire is not securely connected to the speaker terminal and is touching the chassis of the receiver. If the volume is turned higher than 85% this may also occur. If you need to turn the volume higher than this point to get the level you want, you need a more powerful amp.
3) DC Protect = When an amplifier fails this will occur. This will protect dc current from damaging the speakers. When this happens the unit will need to be serviced.
I had a bad 6.3A fuse ? I replaced it and tried to reset. The microprocessor would not reset. I had the exact same results you had.
The chip on the back side of the front IC board was smoking.
Before I attempted the reset I asked Denon if it was worth sending in for repair. The answer was "NO"