okay so i just got my retrofit HID kit in for my 2012 TC and I've been searching around for help to install my harness but nothing was helping! I really want to install the harness with my bulbs! So in the picture below...... is it 2 negative that has to grounded??? IF so... where on the TC???

 

yeah. two negatives. one positive that draw power from battery. one adapter to know if headlights are on and another two separate adapters to control lights.

 

thanks! i thought so! do you know where the two negative could be bolted to? i saw an area next to the battery to be grounded but not to sure about the other one!

 

you can put them onto the negative of the battery if it reaches that far. if not, then just any random bolt works.

 

Just in case someone comes across this thread later, that harness allows you to ground close as possible to the actual ballasts, near each headlight instead of running back to the battery. This help if you headlights are on when you start the car it wont flicker, old style harness does this.