Left Tail Light&Parking Sensors not working (T25 Wagon)

[kit_s]

Hello, I need some advice concerning my Avensis T25 Station Wagon (right hand drive).

I'm having some trouble with the left tail light, specifically the reverse light (the white one that comes on when the car is in reverse.)
I initially started diagnosing the parking sensors (when I got hit by someone on the left rear side of the car) - the parking sensors stopped working.

I disassembled the bumper (quite a lot of work) and it turned out that one of the sensors (the one closest to the left tail light) was badly damaged. I replaced it but nothing changed. Then I read somewhere that the tail lights supply power to the sensors, and I noticed that the reverse light doesn't work (stop lights are ok). I made sure that the bulbs are working, I also changed the relevant fuses (no 8 and 14 in the box behind the glove compartment.) Still nothing.

I suspect the problem concerning both the sensors and the light lies within the connector or the harness, since the light must've been affected by the hit. I'm not sure how to diagnose it though and what to look for. Could you point me in the right direction?