MVS member hu5ker555 shows us how to fix the lumbar support on a Volvo S60 seat on his 2008 S60 2.5T with 168k miles.
So, I was leaning back in my beloved S60 seat when the lumbar support (which I always have cranked all the way up) broke. It is the manual lumbar support operated by the wheel on the side of the seat. After doing some digging around, I found that the likely culprit was a snapped cable.
Surprisingly, I was able to fix it without removing the seat, and without fully removing the seat cover. The seat cover comes apart quite easily at the base. There is a long bar that fits into a channel at the base of the top seat cover. It basically connects the front and rear part of the seat fabric. From there, it was fairly easy to shimmy the leather up enough to see the inner workings. Sure enough, one of the two cable ends had snapped off.
I used some wire cutters to snip of the end of the wire where the remains of the broken cable stop were. Then I threaded it through the hole in the metal seat frame. Next, the trick was to fasten a new cable stop onto the wire. I ended up using a very small ferrel clamp from True Value. It was difficult to get a good crimp on it, but I used my wire cutting crimpers since the surface area on the crimpers is small (more force applied). It seems to be holding and I was able to get the leather seat cover back in place without too much issue.
Hope this helps.