Corolla 2019 multi led signal for external led bar

[Smulle96]

hello, ive got a 2019 corolla TS with multi led (6 pins connector) and am looking to install a led bar behind the grill. The issue ive got is how i would wire up the signal for the relay, ive looked into it quite alot. Ive found the pin that gives 12v on low beam, and i guess ive found the pin for highbeam. Here is where it seems to get tricky. On that pin, when on low beam its reading 5v from pin to ground, but when i put highbeams on it reads 0 with the tester on a ground point and the pin. If i switch the tester probe to positive side of Battery, that wire is now 12v earthed? is it that pin getting earthed that triggers the high beam? if so, could i connect the relay signal with a cable from Battery plus to this specific wire and it will turn on when highbeam gives it earth, but would 12v going into where it only gives 5 under lowbeam fry some electronics?? 
or can i just run the relay parallel to this wire?

i am confused to the moon and back about the way these lights are wired
kind regards