Hey peeps new user here. I have a issue i hope i can kindly be assisted on. On my s80 volvo the previous motor blew a hole in the block straight through and through (dont ask) but me and my buddy put in a second hand "new" motor and everything was done correctly everything went fine we didnt disconnect any brake lines whatsoever but now, we have one electrical connector that we for some reason just CANT find where it goes to or where its other connector is that meets up with it. If it even has one? Car runs and drives fine but our assumption is because of that wire. It now has the "brake failure, stop safely" message on the dash. And the abs light is on as well as the brake light. And our assumption that connection is abs related? We didnt touch or disconnect the pedal pressure sensor whatever its called thats on the brake booster by the brake resivour. And the fluid isnt low at all so im stumped any ideas?

Thats the connector that we cant seem to know where its other connection is, if it even has one, or where it goes or what this is for. Ive seen on other s60 vids this isnt connected either. But im lost