After many years and discussions of how to accomplish getting Android Auto or other such technology into our cars, NavTool designed a module that allows us to mirror our phones to our cars. Other companies have similar modules but they seem to all require AUX inputs, etc. (update: this is also the case with this unit it turns out) which I don't believe Y51's have. Due to a discounted price due to Black Friday, I decided to pull the trigger and purchase the NAVSGF4.0-HDMI+NI4 kit from NavTool for like 50% off. To reiterate, this kit is for the 2011-2013 Infiniti M37 or M56. It *may* work for the 2014+ Q70 but they don't specify that. You'd have to cross reference the part numbers of the AV system in an 11-13 model to that of a 14+ model.
*Disclaimer* - I am not liable for anything you do to your car. This is just a basic walk through and the steps that I followed to get this connected. Additionally, this HowTo is only for making the physical connection of the NavTool unit to the car. I will not be covering how to set up phone mirroring, updating, etc. although I may invariably, due to my background in IT, provide unofficial support or tips (but don't expect that

Task: Install the NavTool NAVSGF4.0-HDMI+NI4 kit on a 2011-2013 Infiniti M37/M56
Time: A couple of hours working cautiously
Prerequisite: You must remove your radio. If your radio is still in your dashboard, please follow this guide: Link
Tools/Supplies Needed:
- Wire strippers
- Electrical tape
- (optional) 16-18 gauge wire in red/black for running an external switch and connecting an in-line fuse holder for protection
- (optional) two terminal on/off toggle switch
1) First, we need to take the NavTool secondary harness (black plug with 7 wires coming out of it) and tape off the green, orange and gray wires like so:

2) Next, now that we have the radio out of the car, we need to find the 20-pin and 32-pin connectors that we will use to tap for various signals. The easiest way to do this is to look at the back of the radio and count the pins and then match it to whatever connector was in that spot. Here is a picture of the back of a 2011 Infiniti M56x (with Bose & Navigation) radio and where the 32-pin and 20-pin connectors go (note: if you don't have the same packages as me, you may have a slightly different radio unit).

3) Here is the pin out chart for these connectors from the Factory Service Manual and what wires we will be tapping into:

4) Here are the two factory connectors along with the wires we have to tap using our quick connect taps:


5) Here are the connections we need to make (disregard NavTools documentation in the PDF titled 'NI4', it is - I'm assuming - for a G35 and the pin numbers are incorrect although the locations are correct):
Note: main harness = harness with gray connector, secondary harness = harness with black connector that plugs into main harness
NavTool Main Harness White/Gray Wire --> Pin 7 on the 20-pin connector (purple or violet wire - ACC) (see next step on this though for more information of how I did it)
NavTool Secondary Harness Red Wire --> Pin 19 on 20-pin Connector (yellow wire - Battery)
NavTool Secondary Harness Black Wire --> Pin 20 on the 20-pin connector (black wire - Ground)
NavTool Secondary Harness White Wire --> Pin 74 on the 32-pin connector (pink wire - CAN-L)
NavTool Secondary Harness Yellow Wire --> Pin 90 on the 32-pin connector (blue wire - CAN-H)
6) Now, we need to take a look at that ACC wire. This wire needs to be 'switched' per NavTool, so I bought an on/off toggle switch from Walmart. I connected my ACC wire like so:
NavTool Main Harness White/Gray Wire --> toggle switch --> Pin 7 on the 20-pin connector
I made all of the wires long enough (using 16 gauge wire from Walmart) so I can store the toggle switch somewhere that isn't behind the radio lol. I have not decided on my permanent location for these yet.
7) Lastly, you need something like a Google Chromecast to mirror your phone to the NavTool. However, keep in mind the following caveats:
- You will not have audio when streaming - NavTool *may* have a solution for this but I removed the device before I was able to figure this out
- You will need a mobile hot spot in your car or to make sure you have hot spot tethering enabled on your phone to utilize the Chromecast while on the road