2003 Volvo S60 Rear Registration Plate lights don't work

[Whitters]

I have had problems with the trunk lock for some time. The small message screen showed the message, "trunk open" even though it was always locked. I could only open the lid with the key in the hidden keyhole and it would not respond to any of the key buttons.
I replaced the trunk harness part number 8645057 and solved most of the problem. Now the registration plate lights will not work. Bulbs are ok.
What I need is the part number for the wiring which is plugged to part 8645057 and carries power to the plate lights.