Originally Posted by 20046.0
The harness which connects everything. Should there be 1 or 2 of them in a 55w 800k h/l 9007, h10 55w 8000k. setup
There is only one that connects to the driver's side - the truck harness on the passenger side is not used since cable from the driver's side routes across the front of the engine bay to power the passenger's side. This allows the lights to work in unison since the lights are electrically charged to switch from hi to lo.