Ok, so I just bought a new kenwood headunit it came with the wiring harness and i matched up the colors to the wires in my 1984 toyota pickup based on the wiring diagram here: http://www.modifiedlife.com/1984-toyota-pickup-car-radio-wire-color-codes/ and the wiring diagram that came with the head unit. but it powers on (i can hear it and i can put a disc in and eject it.) but it wont light up buttons or display anything! please help! not sure what other info to post but yeah