Denon 8500HA red lamp blinking every 2 - 5 days

[Hendrixfan]

I tried calling Denon and the repair center in Syracuse, no on has much further diagnostic but it sets DC codes in protection history, all RBH speakers are at 6.0 -6.2 ohms only does it after a day or 4 ! Always maxed out at - 40 volume is plenty loud here, not sure how they can diagnose this shutdown interval unless the replace amp sections ?

 

[TLS Guy]

I tried calling Denon and the repair center in Syracuse, no on has much further diagnostic but it sets DC codes in protection history, all RBH speakers are at 6.0 -6.2 ohms only does it after a day or 4 ! Always maxed out at - 40 volume is plenty loud here, not sure how they can diagnose this shutdown interval unless the replace amp sections ?

First off check your speaker wiring. One small wisker can cause this or worse. That is job one. Also make sure the unit has good ventilation and may be put a couple of computer fans on top.

Your receiver is a current model, so I assume their is likely warranty involved.

What are your speakers, especially their impedance? They do state the the unit can be used with 4 ohm speakers, but only quote specs to 6 ohms.
Most receiver don't like difficult speaker loads.

Unfortunately Denon's owners are in a shambles at the moment. The owners are Sound United who have been hemorrhaging money and they own a lot of brands. They have an offer to buy from Harmon, who are owned by Samsung who also have a lot of brands. Now this issue of the sale is waiting approval by the monopolies commission and they say to expect a decision by years end. Knowing the incompetence of the current administration, that may be wishful thinking.

Anyhow I have had a couple of bad experiences with Marantz that is a Sound United company.

In had a Marantz 7705 fail at five years they could not repair due to lack of parts. I replaced it with a Marantz 7706 which failed at three months. It has now been in for warranty repair for almost four months, and I can get no information, and nor can my local dealer who is handling the warranty repair.

So, I bought a costly Marantz AV 10, to get my room up an running. This was a major investment, but it has turned out well, as that Japanese built unit is far superior to what I had before in numerous important ways.

So this is just a warning that you may not get good, or required service from Marantz.

Please stay in touch here and keep us informed closely on how this plays out. This helps us advise other members. I have a horrible feeling that from what you say your situation may already be off the rails, but we will have to see. Please stay in touch.

 

[Hendrixfan]

That Samsung deal went through Today, All RBH speakers are at 6 -6.2 ohms.No strands while trying to try with ohm meter attached. It is going to end up as an amp board or 2

 

[TLS Guy]

That Samsung deal went through Today, All RBH speakers are at 6 -6.2 ohms.No strands while trying to try with ohm meter attached. It is going to end up as an amp board or 2

Sounds like it. Thanks for the update on the sale. Unfortunately I expect some of this chaos to continue for a while. Please keep us updated on how this plays out.

 

[Hendrixfan]

So because i can not get a tech to talk to at the Syracuse store where it was upgraded to an 8500HA, i started with an ac infinity fan T9 knowing it does not shut down to a thermal event but a DC code in diagnostics and still shuts off with fans emitting 78 degrees, but again every 2 -5 days, how are they going to diag it UGH

 

[TLS Guy]

So because i can not get a tech to talk to at the Syracuse store where it was upgraded to an 8500HA, i started with an ac infinity fan T9 knowing it does not shut down to a thermal event but a DC code in diagnostics and still shuts off with fans emitting 78 degrees, but again every 2 -5 days, how are they going to diag it UGH

I have never heard of a receiver being upgraded. I assume you mean you upgraded to a new receiver and sold the old one to the dealer for resale. is that correct?

So, in my case we are now at four months with my returned Marantz 7706 and I have heard nothing.

I hear that these recent receivers and pre/pros are not actually fixable, and don't know if that is rumor or not, but it would not surprise me. So, for warranty the repair is replacing the receiver. May be in time you will get satisfaction as the new owners take charge. The problem becomes is that I am really suspicious that the quality of a lot of units from Sound United is highly suspect. See, if you can return it under warranty ASAP, and have it replaced down the road. If you have the funds I would buy a high end Japanese unit like the AV 50 or 40.

I bought an AV 10, and if I ever see my AV 7706 again I will put it up for sale, and hope to retrieve most of my purchase price.

Unfortunately unless you take drastic action you will not have a system for a while.

I would caution you about using units that are not working right. I had a 7705 give trouble at five years. It had an intermittent hum that was on all channels whether inputs connected or not. Then it made an almighty bang through all speakers and I was lucky not to have a speaker damaged. However the rear left channel was taken out.

Marantz would not fix it, claiming no parts available. So it went to the recycling center. This is all a total disgrace and completely unacceptable. I just hope things improve under the Samsung/Harmon partnership. The statements by the Harmon CEO are encouraging, but only time will tell if that translates into improved reliability and service. He did make special mention of improving the quality of the supply chain. This outfit, has only one way to go and that is up. If things don't improve during 2026, that will be a big problem and do lasting damage right across the home AV market. This can't continue without driving custom away.

 

[Hendrixfan]

I have never heard of a receiver being upgraded. I assume you mean you upgraded to a new receiver and sold the old one to the dealer for resale. is that correct?

So, in my case we are now at four months with my returned Marantz 7706 and I have heard nothing.

I hear that these recent receivers and pre/pros are not actually fixable, and don't know if that is rumor or not, but it would not surprise me. So, for warranty the repair is replacing the receiver. May be in time you will get satisfaction as the new owners take charge. The problem becomes is that I am really suspicious that the quality of a lot of units from Sound United is highly suspect. See, if you can return it under warranty ASAP, and have it replaced down the road. If you have the funds I would buy a high end Japanese unit like the AV 50 or 40.

I bought an AV 10, and if I ever see my AV 7706 again I will put it up for sale, and hope to retrieve most of my purchase price.

Unfortunately unless you take drastic action you will not have a system for a while.

I would caution you about using units that are not working right. I had a 7705 give trouble at five years. It had an intermittent hum that was on all channels whether inputs connected or not. Then it made an almighty bang through all speakers and I was lucky not to have a speaker damaged. However the rear left channel was taken out.

Marantz would not fix it, claiming no parts available. So it went to the recycling center. This is all a total disgrace and completely unacceptable. I just hope things improve under the Samsung/Harmon partnership. The statements by the Harmon CEO are encouraging, but only time will tell if that translates into improved reliability and service. He did make special mention of improving the quality of the supply chain. This outfit, has only one way to go and that is up. If things don't improve during 2026, that will be a big problem and do lasting damage right across the home AV market. This can't continue without driving custom away.

Denon has been doing upgrades since the 5800 in 2002, I sent my Denon 8500A to have the 8K upgrade board,,l to the 8500 HA now it sometimes shuts down not from a thermal event but a DC problem in amp section, will keep researching until they are sure what the fix is, as it would be tough to diag a 2-5 day event unless they have seen the same before

 

[TLS Guy]

Denon has been doing upgrades since the 5800 in 2002, I sent my Denon 8500A to have the 8K upgrade board,,l to the 8500 HA now it sometimes shuts down not from a thermal event but a DC problem in amp section, will keep researching until they are sure what the fix is, as it would be tough to diag a 2-5 day event unless they have seen the same before

Interesting. That is the first I have head of that. It sounds risky to me, as those receivers have all the boards packed in like a can of sardines. So the chance of causing a problem would be great. So, I suspect there was either damage or some board did not get seated correctly. It could also be the problem is unrelated to the upgrade.

In any event I think this will be hard thing to sort out for anyone most likely. No one is going to be sure what the fix is here I doubt until the unit is on the test bench, even then it may be very tough.

So your receiver is between 4 and 6 years old, and therefore out of warranty. I see the warranty for the upgrade is only 90 days. So am I correct that there is likely no warranty on this unit currently?

You need to sort out if there is warranty or not. Given the age and life window of AV receivers, I doubt it is worth the cost of repair if there is no warranty.

I have to say that there is no way I would have risked that upgrade especially when the difference between 4K and 8K is minimal, if even noticeable.

 

[Hendrixfan]

Interesting. That is the first I have head of that. It sounds risky to me, as those receivers have all the boards packed in like a can of sardines. So the chance of causing a problem would be great. So, I suspect there was either damage or some board did not get seated correctly. It could also be the problem is unrelated to the upgrade.

In any event I think this will be hard thing to sort out for anyone most likely. No one is going to be sure what the fix is here I doubt until the unit is on the test bench, even then it may be very tough.

So your receiver is between 4 and 6 years old, and therefore out of warranty. I see the warranty for the upgrade is only 90 days. So am I correct that there is likely no warranty on this unit currently?

You need to sort out if there is warranty or not. Given the age and life window of AV receivers, I doubt it is worth the cost of repair if there is no warranty.

I have to say that there is no way I would have risked that upgrade especially when the difference between 4K and 8K is minimal, if even noticeable.

Upgrade was 3 yrs ago, no relation. Lightning does crazy stuff in Cent. Fla ! I will fix myself if needed, Looking for home Warranties LOL !

 

[TLS Guy]

Upgrade was 3 yrs ago, no relation. Lightning does crazy stuff in Cent. Fla ! I will fix myself if needed, Looking for home Warranties LOL !

Good luck fixing it yourself. They do not even publish circuits, let alone a service manual. It seems to me it is time for a new receiver.
If your house does not meet NEC 24 then you need to update it pronto. That is SPD-1 surge protection at entry of your electric service to your home, and SPD-2 surge protection at each electrical panel. If you have solar panels you will need another SPD-2 surge protection on the combiner. Everyone should update to NEC 24.

If you had told the full story on your problem from the beginning it would have saved a lot of time. Getting the full story from you has been like pulling teeth. Thinking you will fix this receiver yourself, is nothing but a pipe dream.

 

[Hendrixfan]

LOL it did not get stuck by lightning, every outlet is double protected. I have the service manual, you are just afraid to fix anything, I did this for 45 yrs !

 

[TLS Guy]

LOL it did not get stuck by lightning, every outlet is double protected. I have the service manual, you are just afraid to fix anything, I did this for 45 yrs !

Well, what the Hell are you asking us for?

 

[Hendrixfan]

Well, what the Hell are you asking us for?

Cause Denon is not even familiar with DC codes, Ill figure it out,diagnostics is what i did for GM electronics, but worked on everything also for repairs, Diagnostics is 90% of all repairs

 

[flyboylr45]

Upgrade was 3 yrs ago, no relation. Lightning does crazy stuff in Cent. Fla ! I will fix myself if needed, Looking for home Warranties LOL !

Central Florida huh?? I may know someone with a working, homeless X8500h that may be willing to let it go.

 

[Hendrixfan]

Central Florida huh?? I may know someone with a working, homeless X8500h that may be willing to let it go.

Maybe, but hell you only live once, poss a 15 channel Denon while i get time to repair this one !

 

[Hendrixfan]

Well, what the Hell are you asking us for?

You are not US, we are here to help each other, you are 25 yrs behind on just upgrades !How you can be on this site for what you know is strange, I learned much from Gene and his awesome info team