Dashboard lighting

Hello, I just installed a new panisonic CD deck in my 97 Jetta GT. I purchased the $30 piece from future shop for Jetta's of my year to connect the wiring in the car to the back of the Deck... however the piece only has 2 slots to plug in and there are 3 groups of wiring that are coming from inside the dash that were connected to the old stereo. I plugged in the two... now I have 2 extra brown wires (from the back of the deck) and I have an extra group of wiring not connected. now my stereo works but my Dask board lights won't work. Are the dash board lights powered threw the stereo? What am I missing?