I just purchased a mint 2007 C70 t5 with 32k miles. It is beautiful! The Dynaudio sounds great, however the subs are not working. I have activated it on the head unit. I felt the speakers behind the back seats, I just don’t know where the amps are to check the fuse? I believe the subs are on their own amp. Still looking for information on this car. Any help is appreciated.

 

on the gen 1 C70s the amp is in the trunk on the left side behind the panel. Did you check for the same on your car? As to fuses, you should see a listing in the owners manual for the various fuse box locations or you can find wiring diagrams/ fuse box details on line. Again I suspect there's a fuse box in the trunk or by the glove box.

 

Thank you! I have procured some wiring diagrams. I plan to look at it this evening. I checked the obvious subwoofer fuse in the engine compartment, but it was perfect. I even swapped a new one to just pretend it would work. It was late so I had to give up. I am going to bust out the multi-meter and see if I’m getting voltage on the line once I find the amp. That’s pretty much the only thing not working on the vehicle, other wise it’s a cherry. My wife thought the stereo was amazing without the subs, lol!

 

I will be brief. The input signal line is fiber and not analog. The sub amp had the T connector just looped into itself. I removed the mains amp and tied them together. Subs are working great. So the previous owner must not have known that his subs did not work for 15 years. My wife is stoked and we’ll get some use out of them. First time I have ever seen a digital connection to factory amps. Makes sense to isolate the noise. My friend thought I was making it up!

 

Excellent. Volvo went to Fiber connections beginnng in 2005 or so along with oddly shaped bezels making after market installs a PITA. LOL this has pissed of S40 Gen2 owners looking to upgrade for years :-) I figure it was some form of theft deterrent!!