Install grand prix navagation

I just purchased a Grand Prix GXP and it has every option except engine block heater don't care and navigation. I know I need to have the nav unit unlocked but I have a couple of questions. Can anyone tell me without guessing what the 4th electrical plug is on the back of the nav unit not counting the radio antenna port?

Port 1 and 2 are the factory radio plugins, port 3 is for the nav antenna and port 4 is for?? Once I install the nav unit and plug in the 3 know plugs will I need to install anything else to make the nav work as intended from the factory?

Thanks for your help. Last edited by Cheezehead; at AM. I received the GPS antenna ACDelco and located where the antenna would have been installed from the factory and the pig tail coming from the antenna is 12" which is way too short for a direct connection to the nav unit 36".

I assume the pig tail plugs into the harness somewhere near the mounting location but I don't see a plug nor do I see a plug coming out of the harness near the nav mounting location. Can someone tell me if I'm on the right track or if a factory nav unit install in a non-factory nav installed Grand Prix is just too hard? The smallest plug is for the microphone.

I have one if you need it. Any two wire microphone can be wired in for audio input. Otherwise voice commands won't work. The smallest one not counting the radio antenna plug is for the GPS antenna upper right hand corner. The plug in question is the white plug lower left hand corner of the picture. The far left plug. I didn't mean the satellite plug. Description: With navigation system, code: ui6. With navigation system, code: ue1. More Info. Notes: Order by description.

More Notes. Fits: Buick: Enclave Chevrolet: Traverse. Add to Cart. Replaces: , , , Description: With bluetooth, with mp3. Code ufu. Not For Sale.

Description: With navigation, 2nd design. Fits: Chevrolet: City Express. Description: Without navigation, with bluetooth. Description: Without navigation system, code: ui4. Without navigation system, without onstar.

Description: With navigation system, code: ui5. Languages English Bahasa Indonesia. Home FE News. Derry Munikartono. Follow Crash. Latest Articles. Marc Marquez returns to training for first time in three months. It appears that your browser has cookies disabled. The website requires your browser to enable cookies in order to login.

Please enable cookies and reload this page. Help Center Quick Links For additional assistance, visit the Help Center to find information specific to your vehicle including how to install map updates and tips for using your navigation system. Help Center. General FAQs. Shipping and Return.