I'm new to this so please excuse my naivety. I recently bought a 2006 Limited V8 that has the navigation system. When I bought it, I could use the tilt and open functions but now they don't work. A dealer says that if I wanted it replaced it would be about $2500 for a remanufactured one!!!! Does anyone know what the model number or MPN is for this? I'd rather not pull it out to get the details if I don't have to. Thanks for the help!