So i have an Alpine CDA-9886 headunit installed on my car. I bought this metra antenna adapter
Honda Antenna Adapter Motorola Male to OEM Female at Crutchfield.com
but it just doesn't work... i attached the factory radio harness the motorola end adapter and plugged it into the back of the headunit. am i missing anything or doing anything wrong? i can just let the blue wire hang loose right?