[Parknest]

I've just read this thread from the beginning and it partly relates to my own "anti-skid service required" issue as I have a CEM 1A64 error code.

@moorgate mentioned broken CANbus wires and my first thought was to test the wiring with an oscilloscope. These can be had for a reasonable price these days and it is a good way of checking the integrity of the CANbus network. A simpler test is to check the resistance of the network (60 Ohms if I remember correctly). If you get 120 Ohms then one of the terminating resistors that are located at each end of the network has failed. I think the resistors can be embedded in a module.

I have a Haynes for my own XC90 but the wiring diagrams aren't of much use when you're trying to diagnose problems with modules or the CAN network. I did manage to locate a proper wiring diagram for the P2 platform (V70, XC70 & XC90) which has helped me.

Volvo Diagnostics seems to have a good reputation going by the forum posts that I've read and would be worth a try.