Sub-woofer output not working

The receiver's out put sections are grouped in pairs. Front left and right in one output, rear left and right in second output, and center channel and sub output on the third. Sounds like a semiconductor or semiconductors have gone bad in the center & sub output.

Short circuit protection energizes. Check for any external short circuit with connecting sires to sub woofer. If it found OK, the sub-woofer output amplifier section circuit inside the set is fault. Short circuited component/s. Check and replace them. Contact any service technician. If you wish to get some details; check the site linked here. Pull up older posts.
http://electronicshelponline.blogspot.com/

It sounds like the problem is not with your VR-606. If you hear a hum from the sub, the problem is more likely to be in the sub's built-in power amplifier. However, it is worth resetting the amplifier to factory presets. To do this, unplug the power cable from the mains supply and reconnect whilst holding down the power on/standby key. If the hum persists, connect any powered speaker to the sub-out socket, power on and listen for the hum. If no hum then suspect the powered sub amp. Turn the sub on with no connection to the Kenwood VR-606. If hum persists, the sub has a problem and will need to be replaced or repaired. By the way, you said there is a low frequency hum through the 'speakers' for about 30 mins. Is that all speakers or just the sub? Hope this helps.
Cheers, Don.

I suppose you could, but you are talking about a driver (speaker) that was not designed for that cabinet size and amplifier used in the Kenwood, There are differences in speaker design besides power rating and impedance.

I inherited a Kenwood SW 505 Sub woofer. I don't know if it works I plug it in but no lights.

http://www.kenwoodusa.com/Support/Car_Entertainment_Owners_Manuals/ You can download the manual from Kenwoods site. While the unit is in Standby mode, press the B.Boost button for a second or two. You should now be in the Menu. Select SWPRE. Now chose SW from the (R*/SW) options. The output of your CD player is now a dedicated sub woofer output. I hope this is what you meant. There are many settings regarding the sub woofer and generally the sound in whole. Getting the manual is highly advisable. dreamsystems.

Is the 407 set up to drive the unknown sub. It's not just plug n play.

The manual will guide you, around page 15. Also refer to your subwoofer manual. Try retrevo.com for that one.

http://www.retrevo.com/support/Kenwood-VR-407-Receivers-manual/id/480ag200/t/2/

on the back of your receiver is a subwoofer pre-out, connect one cable here, and connect the other end of this cable to your subwoofer - line level in. (depends on your subwoofer and receiver) but that's how mine is connected. yours will be similar.

Your receiver should have an RCA connector on the back panel that will be marked "sub woofer" or "LFE out". That connects to your sub woofer with a standard RCA type cable. Also, some powered subs have left and right speaker level inputs and outputs in which you would indeed run the sub woofer through the speaker outputs. The down side of that type of connection is that the line level converter inside the sub woofer will take a slight amount of your receiver's output power, although that is rarely detectable. Also, if you have a Dolby Digital receiver, using this connection method will take away systems ability to accurately control the low frequency effects of a soundtrack.

Good Luck,
BB

I felt supid this morning.
I bought a high end cable for my subwoofer.... and it did not work but a regular RCA Cable did. When I went to put the cable back in the package I saw an arrow pointing one way, I turn the cable and it works great.