Question Harman Kardon Hkts210sub stopped working

[nilz18t]

Hi guys

I have got a HKTS16 Harman Kardon surround sound system setup and have been using it for a couple of years now with no problems at all, however last week, all of a sudden the sub stopped working.

The Sub is a HKTS210SUB/230 and this is where it gets strange... There is power going to it, it is set to auto on, so will come on when a bass signal comes to it and goes off when it doesnt get one for a while, so seems to be working fine, however there is no sound coming out of it at all.

I have run a test tone through my amp and it sends a signal to all the other speakers but nothing out of the sub. I took my sub to a mates as well and tested it on his amp too to make sure it wasnt the amp.

I have looked online and found nothing on this at all apart from a resistor that may have blown, which I have replaced and tested again today, but still no sound.

Any ideas or advice would be much appreciated, really dont want to get rid of the sub, as I am really happy with it.

Thanks
Nilz

 

[fatboy frank]

Any internal fuse that could have blown?

 

[nilz18t]

Not that I can see. Also with a blown fuse would it still power up and run bar the sound?

 

[fatboy frank]

No idea, was just a thought as i do know some have internal fuses too, which might be protecting other circuits/components and stopping output. As i say it's just a guess, but worth checking if you can gain access easily enough.

 

[nilz18t]

Hi

Thanks for coming back, as far as i could see inside there isnt another fuse, its really wierd as its acting as if the speaker has just been disconnected, even if you connect or disconnect the lfe, there is no thud or anything like that at all, however everything else is running as normal.

 

[A7madYG]

Hey nilz18t, did you solve the issue?
I'm currently facing the same issue, I tried to open it and I couldn't see any fuse inside.
thanks

 

[jasonsmith559]

View attachment 1141829
I have attached what I found to be the issue on the sub I repaired. It is labeled diode D4 on the board and is circled in red. The original is a 200V 1A Schottky and on the unit I repaired it was shorted. In the picture you will notice I replaced it with a higher current diode which is part number SB3200 or SR3200 rated at 200V 3A. Remember to observe the diode polarity before removal so that you will be able to easily install the replacement. Also if you replace the diode with the higher current version the circuit board holes will have to be enlarged.

 

[nilz18t]

@jasonsmith559 Thanks for this, I assume you resolved the issue after replacing this diode?

I am sure I did replace that, however still refused to work. I more or less replaced the majority of the board and still no joy!!

I may go back and retry to see if I can get it working.

 

[Sylvester1]

View attachment 1141829
I have attached what I found to be the issue on the sub I repaired. It is labeled diode D4 on the board and is circled in red. The original is a 200V 1A Schottky and on the unit I repaired it was shorted. In the picture you will notice I replaced it with a higher current diode which is part number SB3200 or SR3200 rated at 200V 3A. Remember to observe the diode polarity before removal so that you will be able to easily install the replacement. Also if you replace the diode with the higher current version the circuit board holes will have to be enlarged.

Hey,

This worked for me!!! Replaced the Schottky diode(I couldnt get my hands on 200v1A so i replaced it with 200v 3A) and the sub works very well, couldnt be more happier!
Thank you very much!

 

[Bgp123]

Hi All, I just came across similar problem where this exact HK subwoofer doesnt power on.

I purchased the HKTS200 surround sound system(6Pc) back in 2015. Perhaps this is a commonly failed part. HK support would not replace or fix as its out of warranty.The Shottkey diode relatively in expensive on ebay. Beats buying a new subwoofer

After reading this I figured injustice try to pull out the diode before buying new one.

I was able to solder out the D4 diode. Its labeled with MBR1200 / 3509 Label on it.

Can anyone tell me if it's worth just replacing this without any testing? If I had a multimeter could I test the failed diode vs working one?

I have little electronic background, so could use your guidance.

I've attached some pics in case anyone else has same problem.

Thanks.

 

[Sylvester1]

Hello,

You can test the diode with a multimeter in "diode" mode.
Heres a youtube video on how to do it I should also tell you that be careful when you're messing around with amp boards, the windings or the caps can keep an electric charge even when its not plugged to the socket.

 

[marcbyron]

I am looking at the service manual, which mentions a MBR1200, and others here on the thread mention the SB3200. Are these interchangeable? Both are Schottky Rectifier Diodes