In a CLOCKWISE direction, starting at the top left, I’ll describe the connections.
Top left = 12V power. Connect this to your battery. I’m working on the driver’s side on my truck so I connected it to the driver’s side battery. This power lead contains an inline 30 amp fuse so the harness is protected against over-current.
Top right = This lead contains both a connector (black with a red and black wire going to it) and a pigtail with a barrel capacitor and ground terminal. This black connector is what connects to the HID bulb harness connector you wired up in step 6 and connected to your factory headlamp connector inside the headlamp housing. Again, pay attention to the polarity here. You want the positive signal from the factory headlamp connector (white wire for me) that is now connected to the HID bulb harness (blue wire for me) to connect to the red side of this connector, or, the same side that the capacitor pigtail is on. Sounds confusing, but it’s pretty straightforward.
Bottom right = this is the connector for one of the ballasts. There is a positive and negative side (red=positive, black=negative). The black wire has a ground terminal on it.
Bottom left = this is the other connector for the other ballast. Same thing.
Middle left = this is the relay itself.
This is off cumminsforum for a 2011, sounds like it doesnt matter which one but you be the judge.
