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My subwoofer had no sound or power. I replaced the ZN3 diode and now I have power but still no sound. Any suggestions?

Posted by Chris on

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Steve K

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If this is a boston acoustics sub, then I assume you replaced ZD3. You also need to check R9 on the back of the board. It is a surface mount resistor and should read 10 ohms. This resistor sometimes goes open when the diode shorts.

Posted on Jun 09, 2015

Testimonial: "I checked R9 and it reads 11 ohms so I am assuming it is fine. I did replace ZD3 which restored power but still no sound."

  • 2 more comments 
  • Chris
    Chris Jun 09, 2015

    I checked R9 and it reads 11 ohms so I am assuming it is fine. I did replace ZD3 which restored power but still no sound."

  • Steve K Jun 10, 2015

    Look at C18 & C27. If they have any signs of venting (usually shows as what looks like putty bubbling out of the body) they need to be replaced. that's the only other commmon problem I've found with these subs

  • Chris
    Chris Jun 10, 2015

    ok. I will check. Are those capacitors? If they are bad would you know the specs them?

  • Steve K Jun 10, 2015

    they are .1uf/250v caps

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