I've had my 01 V70 T5 for 9 years. Recently, I tried to lock the car with the remote and all 4 doors lock properly, but not the tailgate. One can just open the tailgate, and sometimes the security alarm does sound. There's no audible click either at the tailgate when trying to lock the car. I've been searching a bit, and a few recommendations say that the harness wires may be broken where it passes through the left hinge area. The fuse is good. Other ideas?

 

So, I did have to splice together 5 broken wires coming through the left hinge. This got the latch working again. HOWEVER, the tailgate still would not unlock with the remote. It turns out that there's a spring on the release handle that becomes weak or broken (other posts confirm this). I bought a used handle assembly on eBay and installed it (Volvo #31253018). This fixed it. Now, it locks and unlocks properly with the remote. Here's a link to a YouTube video showing the problem with this spring inside the release handle: