HU Install - left over harness?

[MidKnight]

Hello all:My wife got me an early Christmas gift of a new Kenwood HU from Crutchfield, so it came with all the needed brackets and harnesses. My question is this, when I unplugged the factory radio, I took out 2 harnesses and the kit only replaced one of them. With the old harness just hanging out, I don't see any lack of function.Could somebody let me know what the heck that extra harness was for?Thanks for any/all replies.

[DoubleBaril]

i dont think you need to worry, as it didnt affect my aftermarket deck either.It may be some sort of dimmer control on the factory deck, but wasn't needed for an aftermarket one.I'm guessing Audiovibe will chime in soon enough