Cannot find brake light wire. Please help

I have two plugs..each with 4 wires going to the left and right tail lights. Of the 4 wires I found Ground....park....Reverse..and direction light...
If I press the brake..no power is found and if I unplug both connectors to each tail light the brakes light stay on both sides
Clearly there is another harness to each tail light that has ground and positive...but I cannot find it..
Any ideas??

 

I forgot to mention this is a 2018 Prius two...( I think it is a two..I don't know how to tell which it is)