No, it's the wiring sleeves - some way up that will have the markings - but you may n,ot be able to see it without removing some of the insulation.
Anyway, back to the faults and you obviously have a some communication problems on the CAN networks that connect these systems. My suspicions are the engine fuse box.
These are non-user serviceable, but supply the BSI and the ESP and Engine ECUs and the gearbox locking relay - all these other faults could be symptoms of the main failure of the engine fuse box. There is no guarantee - but given the sheer quantity of these faults this is the one common denominator.
Sometimes the relays embedded in the engine fusebox can fail and this will cause multiple problems.
I would start by checking all the battery wiring, and all the fuses in the engine fusebox first - but again with so many faults it would mean there would have to be more than one fuse shot in the engine fusebox - so I still think this is a likely suspect.
The part number of the fusebox for your X7 is: 9807028580. The cost from Citroen is not as expensive at (UK) £95.71 inc. our 20% VAT - so about 1188.55 Swedish Krona at today's rates.
So looking at the Engine Fusebox, there are direct supplies to the Automatic Gearbox (F7), and multiple supplies to the BSI that in turn is responsible for communication to other systems that are on your fault code list. If it was one or 2 specific faults, then it would likely be a single connection / electrical connector / sensor that would be the culprit. I've also heard the speed sensor being responsible for a load of faults - as this relates to the engine ECU and all systems that are dependent upon this - but again - too many unrelated systems to pin it on an engine speed sensor in my opinion.
I don't think there's much you can do on these test-wise, but if you have checked all your obvious connections, wiring, wiring plugs / battery and supply wiring, then for the price of an hours diagnostic session at a dealer an engine fusebox may be worth a shot.
Consequently, I haven't uploaded over 33 fault code explanations as I don't think under the circumstances it would be helpful given the sheer number of faults and may actually confuse the issue - plus the time involved to do this.