Sub woofer keeps blowing fuses

I would expect a shorted component in the power supply

Link for the service manual: http://elektrotanya.com/pioneer_vsx-305_405.pdf/download.html On page 50 of the manual (36 of the pdf) it says for the "Sub woofer pre-out jack (Not available on the VSX-305 model) If you want to boost the low frequencies, connect to a subwoofer power amplifier" Your model will not drive a sub-woofer with out another amp. His sub may be a powered sub?

If a fuse blows it won't self-heal when you cycle power.

Swap the subwoofers between the two subwoofer speaker feeds. Maybe it will stay with the channel or maybe it will follow the speaker and make next steps easier.

Where was it sitting before it was moved? Did it have it have more ventilation and keep cooler? This sub has a powerful amplifier in it. If it got moved to an area that restricts air circulation around the sub more it is possibly overheating and causing fuses to blow. Put a fan on it and make sure it is on a hard surface or up off the carpet at least to keep the bottom side cool as well. Also when one moves a speaker it's often to put it into a more convenient area to be able to turn it up louder with less disturbance to others. This will draw more power and create more heat within the amplifier than it's previous location. If this is so keep it as cool as you can and turn it down every so often to give the amp a rest. The key here is to keep it cool as you can. One thing you never want to do is put a higher rated fuse in than the unit is rated for. Always use factory recommend fuse rating.

If you have replaced with the correct rating and the fuse blows off then you will need to check for higher current drain in the sub woofer or the network. After replacing the fuse load up the subwoofer slowly, reduce the bass and as you increase check at the point the fuse blows off. Now we need to analyse if the rating of the amplifier you are using is rated for the subwoofer. If your subwoofer has a higher rating you can increase the rating by about 25% and check again. Some amplifiers give a very higher voltage on full bass which could result in such a condition. Moderate this and check again. If the fuse stays Ok you can continue with this new rating.Otherwise the output of the amp at higher volume needs a confirmation. Hope this helps. Good day

You should open it up and look for a short. Usually, an exposed wire is touching metal. Wrap the wire with electrical tape and look for a ground wires that are loose. That will blow fuses too.

hi
it sound to me that when you biamp and driving speaker and woofer , you are over loading the fuses , suggestions
uprate the fuses till they stop blowing

If your fuse keeps on blowing after you cg=hanging,that meens that there is a shortage.check it first using the multimeter.good luck.

You will only blow fuses and resistors if there is a short of some kind you can change fuses, resistors and capacitors all you like if you don't find the short they will just keep on blowing. It maybe something as small as a bit of conductive material or fluff or dust on chip board wipe board down make sure it is clean (a clean toothbrush is perfect) and there are no signs of burns on either side of the chipboard befor you change anything. If there are burns or greenish build up clean them with some metho or water on a cloth not to damp though and make sure Burn or corrossion hasn't taken off the protective layer on the board.
Then try new fuses. Hope this helps you

Hi,

The fuse blows when the current that passes through it are beyond its rating. This could be brought about by excessive consumption of the load, in this case the amplifier powering the sub-woofer.

Repairs would involve component level and require that you be familiar with electronic components and circuitry, use of a DVM and a soldering iron. Often it is just the finals that needs to be replaced. Of course we cannot discount the possibility of other components or section such as the power supply.

The smoke indicates something heating up such as a resistor or diode or a capacitor.

Should you be uncomfortable opening the unit and doing a DIY (do-it-yourself), then perhaps you need to seek the services of a qualified professional.

Should the downtime and cost of repair be no longer economically reasonable, purchase of a new unit might save you further trouble.

Hope this be of initial help/idea. Pls post back how things turned up or should you need additional information.

Good luck and kind regards.

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