It's a VQ rear seat cig lighter and will be handy to have it wired in. Any one have the wiring diag for this option.
I would just tap into the front cigarette lightr plug. The colours should be the same so shouldn't be hard to match up. If not get a test light a figure out what goes where.
Probably your headlights. When you turn your lights on it turns on a light inside the lighter. It's probably uses the yellow for earth so the blue would be a control wire for the light inside it. Earth the yellow and put power to the blue one and it should light up.