I know I’m a little late to the game but I’ll bet that plug is for the GPS Antenna. The GPS antenna in not the one on the roof (or the trunk for roadsters) it is in the dash. Here is my response to another guy when asking about trying to install a factory nav system in a non-nav.

Hi Vabam no your not to late that idiot wont take it back and he insist that its from a 370z i have the gps antenna and everything else as well, i cant find the wiring diagrams for my specific parts,all i got seems to be from a 2009 but doesn't include the one connector i am wondering what the hell it is even from the manual book the one connector shown as the displays connector in some other German forums they say the small one is the can bus plug and the one shown in the manual as display plug he describes it as totally something else that is what drives me crazy i cant find anywhere the manual for my parts :/
I know i have to rewire everything i recreated the whole cable wiring it all seem to work but as soon as i connect the ones that the German forum describes to be the canbus pins high and low to the ones on my ECU all dash instruments die, shut down completely so i am wondering either the ecu is not compatible wich is a question even nissan here cant answer me 100% ,they think the ecu might not be compatible ,or those are not the pins i was supposed to connect as can bus to the ecu ,either way i gave it up for now couse i dont know 100% what is what and dont wanna screw something up on my car :/ so any further infos regarding this matter would be helpful to me and i guess to many others trying to figure out the same thing as me :/

I'll take a look at the FSM soon but I'm sticking by my original comments. The NAV system requires a different harness and IMO you can’t splice or adapt the Non-NAV wiring harness to work with the NAV system. One thing is for certain the HU you have is not a 2009. I’m betting 2013 or newer at this point due to the extra piece of equipment you have that I’ve never seen before; bottom pic, look like a DVD/CD drive. I noticed that you are in Germany; Europe might have gotten a different system than us here in the USA at some point after 09. Every one had the same NAV system in 09 which had the CF card reader on the front. Do you have the Germany/Europe FSM (Fleet Service Manual)?

Maybe it is the reason that mines somehow different ,i saw in a British forum a guy says he has the 2009 and it looks exactly like mine ill add the link dont know if i am allowed
Reverse Camera + iPod control on 370z without Connect Premium? - I.C.E & electronics - 350Z & 370Z UK/
And he has the exact OEM part number as mine so it should be from a european 2009 maybe Us version had other systems .when u say nothing fits yes i know ,only the power harness fits the one that goes to the bose amp and speakers ,the biggest problem is the AC unit that communicates through canbus and not direct as it does right now without navigation models . here some more pics of my parts maybe they it helps .
Thanks for the Help!!!
http://www.the370z.com/attachment.ph...1&d=1479127042

http://www.the370z.com/attachment.ph...1&d=1479127042

http://www.the370z.com/attachment.ph...1&d=1479127068

http://www.the370z.com/attachment.ph...1&d=1479127068

I’m not seeing your pics and attachment. To be honest unless I have the 2011 FSM and 2009 FSM for the Euro spec Zs I’m not going to be much help. The US 2009 Nav system has fewer parts so less connections and so on. One problem that me and few others are having is the rear defroster not working after the conversion. I literally just found this a few hours ago; with the US spec NAV system the rear defroster is turned on by the head unit (AV Contoll unit) and on the Non-NAV it’s turned on by the AC Auto Amp (WTF Nissan). I’m working on a solution for that as we speak.

My guess is that the 2009 Nav units were borrowed from another Nissan (or Infiniti) vehicle and cobbled to fit in with the Z. I can't see how that would be any better or cheaper for Nissan, because of the harnesses, but I'm no car designer. YMMV

i am searching everywhere to find it with no luck :/ im trying to figure every pin out with an oscilloscope right now so far the can bus are correct :/ the weird part is why they instruments shut down after i connect it to the main car canbus flow the ac harness on my and the navigation model are the same as far as i can see the diagrams only it connects through pin 1-2 for can bus and u just unplug the 6-7 or something that where used to communicate direct , arent needed . ill try to contact nissan for the manual book even though i doubt they would give them out so easily :/
The defroster is not that important as to make it work first :P but thanks for the notice and the great help your giving me :)
Btw do have any tuts from anyone thats has pulled it off ?

Southark you might be right btw couse when i google my oem part numbers they come up as Murano or infinity, so Nissan might had gone down this road but the weird part is i already looked up theyre manuals and still not same as mine :/

ok update
So i got a complete harness for the navigation and i managed to plug it all correctly and start up the navigation outside the vehicle, the problem i am facing now is the Green boxed message "Secure" apearing on the screen i can get in the info menus but not more
As far as i know the unit has to be reprogram to my cars anti theft system with a new code now i recognizes its from another car with wrong code..
I called more than 10 nissan Dealers and none had a clue on what it has to be done :/
they all told me to go by and have it checked but i am not on mood to give another 500 euros or so just to check for something that might not work at all!
So does anyone know if it simply need to be reprogrammed to my vehicles anti theft system or to completely remove the code validation within the navigation unit ?
Thanks ! :)

The system is deeply programmed to work and communicate with your vehicle, lights, climate control, radio and so on. I believe what you're seeing is it's locking down from not talking to the car. But once again you're going to need not only the harnesses but the bose amps and speakers to get everything to work. It's really not worth the work to put it in and what you gain.

Hi. I went to Nissan and they told me it has to get reseted by Clarion theyl have to send it to them and they gonna set it back to New so once i connect it to my cars can bus it will take the code from my ecu and be recognized and mine .it stores the Navigations Code and Vin number inside the eeprom and it binds together with that certain vehicle once first ignition is turned on. My car has already a BOSE system and amp i made my self a harness cable from the one i bought the navigation and everything works now ill have to pay around 200euros to clarion to set it back or try to hack it my self by reading the navigations eeprom then my factory radion and rewrite the code of my ecu to the navigation i will let you know if the experiment work and how you could do it your self if needed :)

By passing the stock 2009 navigation system
 

Does anyone know what color is the speed and brake wire? Wanna by pass the stock 2009 Navigation. I been looking online and coundn't find anything.

Have to give you a little grief on this post. It is a little off topic for this thread. If you have a question, start a new thread please. :tup:

FYI I have responded to your PM.

Hi simon I have got similary problem but I need change my us spec HU on EU spec navi when I put to car used EU Hu after one minute is secure... Can You may help me something...? I lost many time to find security anty thef but no succes yet :(

simos please contact With me if possible or request to You give me @ ,skype or phone I need contact to do my nav or contact to clarion becouse i cant find nothing who can help me