DIY – NAV System Conversion with working rear defrost
 

DAMAGE DISCLAIMER: By using this DIY, the User assumes all risks associated with the use of this DIY, including any risk to User's vehicle, ECU, BCU and any other electrical system, which might be damaged by the owner attempting to make a modification to his or her vehicle. More specifically this a modification that I did to my vehicle, and I am sharing what I did to make my system work, I am not in any way shape or form telling you to do this modification, this is solely on YOU. I shall not in any event be liable for any direct, indirect, punitive, special, incidental, or consequential damages, including, without limitation, lost revenues, or lost profits, arising out of or in any way connected with the modification to your vehicle, through the use or misuse of the information or lack of information on the 370Z forum Web site or with the delay or inability to use this web site, or from any information, documents, services, software, or other material obtained through this web site, or otherwise arising out of the use of this web site, whether based on contract, tort, strict liability or otherwise, even if you the owner has or has not been advised of the possibility of damages or any unseen damages that occur from this specific modification. I shall not be liable for any loss or injury caused in whole, or in part, by its actions, omissions, or contingencies beyond its control, including in procuring, compiling, or delivering the information, or arising out of any errors, omissions, or inaccuracies in the information regardless of how caused, or arising out of any user's decision, or action taken or not taken in reliance upon information furnished.
This is a DIY (Do it yourself) and I hope it will assist those of you who want to change out your Nissan factory Navigation Systems to an aftermarket solution.
I did this to conversion in order to use the WorkShop12 tablet kit which can be found here: https://workshoptwelve.com/nissan-370z/

I have read a lot of posts within this forum about people despising Nissan’s navigation system. My experience is that it has major issues with finding its way and it’s just overall a bad design. The upgrade costs in itself are way too costly. I have read many posts that say that this modification is not possible, and supposedly many of those who tried have epically failed in attempting to do so. I can only share with you my modification which did work. I have used the instructions from http://www.the370z.com/diy-section-d...version-2.html and updated them to include the rear window and mirror defrost fix. Your Z might not be the same as mine but you can easily check your cars wiring described below to see if everything matches. This is my mod and solely the information on what I did. If you do this - anything you attempt to do is on you guys. I wish you all the best and please provide feedback. I hope it helps.
The WorkShop12 tablet conversion works and all other wiring to do their conversion is on their website. This write up is only to do the navigation to non-navigation in order to have a fully functioning AC. This does not include instructions to remove your dash trim or the stock navigation system.
So now down to the question at hand, the Navigation System conversion. It is pretty straight forward and not complicated:
Parts Needed:
1. Pigtail from the Standard HVAC Controls – I purchased 10P025 NH Female with 10 terminals from NH-025.
2. You will also need to purchase 11 pins from site above (buy a few extra in case you break one).
3. Standard HVAC Controls (3 Dials)
4. HVAC Amplifier (White box under the radio)
Non-NAV A/C Auto Amp part # 27760-1EA0A
NAV A/C Auto Amp part # 27760-1EA1A
5. Double Din Conversion Kit. (This is for your radio connection.)
6. 18 AWG wire (at least 15 ft of wiring)
7. Some basic Wiring knowledge.

There is no difference between the Nissan Navigational system(s) and the Nissan Non-Navigation System(s), except the two use a different way to send signal to control the AC:
They all include A/C setting(s) of:
• Automatic mode
• Temperature range(s)
• System blower speed(s)
HOWEVER (THERE IS ALWAYS ONE) being that the Nissan Navigational system(s) all have the ability to display on the screen the luxury options such as:
• Fuel Economy
• Maintenance Stuff (Alerts)
• Where am I
• Traffic Info
• Weather Info
• Navigation Version
• Other Info

Conversion of the Navigation to Non-Navigation:
The HVAC system:

1. Disconnect car battery
2. Remove navigation A/C Auto Amp and plug the M66 connector into the non-navigation A/C Auto Amp (this is a 40 pin connector)
3. Add 4 pins to the M66 connector. The non-nav has 4 extra pins off this connector that you must add. You will add pins to slots 6, 7, 26, and 27. [6 is for TX(AMP>CONT), 7 is for RX(CONT>AMP), 26 is for Rear Window Defogger Feedback Signal, 27 is for Rear Window Defogger On Signal]

Notes/tips: If you want a cleaner install, run each line one at a time. First connect the pin to one end of the wire you are running. Install pin into connector, run line to opposite connection and install pin or splice into needed location. How I made all my pin connectors: I took extra wire from a left over radio wiring harness, stripped one end of the wire, only expose a few mm of the metal wire, just enough to fit the middle space of the pin (you will see the two middle metal crimp spots), you will see the top two metal crimp spots on the pin, those should be crimps around the wire (NOT the exposed metal). I used needle nose pliers and crimped down one top side first and then crimped down the opposite side over the first. I did this for the top two crimp spots first, and then repeat for the middle section over the exposed wire you stripped previously. I made about a dozen of these with the wire length about 6 inches.

When installing these 4 pins, what I did: I took a bobby pin from my wife and snipped off one end to make a small flat metal end, then make sure you have the pin end facing the correct direction. I used LONG narrow needle nose pliers (the mouth needs to be long enough to reach over the bottom of the connector to the top of the pin you are adding). I first slide in the pin with my hand as far as it will go, I then use the bobby pin to try and gently force the pin down, when it doesn't want to go, I then use the pliers, be gentle as you don't want to break the pin, it slowly forces it in, then use the bobby pin again with the pliers to force the pin down to the bottom of the harness. Repeat for the other 3 pins.

Picture: Nissan 370Z Forum - 2SIC4U's Album: Nav Conversion AC - Picture
http://www.the370z.com/members/2sic4...94-ac-m66.html

4. Add 6 pins to the M67
Picture: Nissan 370Z Forum - 2SIC4U's Album: Nav Conversion AC - Picture
http://www.the370z.com/members/2sic4...connector.html

Note: If you want a cleaner install, run each line one at a time. First connect the pin to one end of the wire you are running. Install pin into connector, run line to opposite connection and install pin or splice into needed location. Repeat notes above to make 6 pins with wires. This time, pop off the white bottom cover of the connector. Slide one wire at a time up through the bottom of the harness, followed by the pin, make sure the pin is facing the correct way. If you look through the bottom of the connector you will see a plastic retaining clip/pinch spot, that spot needs to go into that middle spot of the pin to hold it in place. Ok, use the same method as notes above to slowly force the pin in from underneath, repeat for all 6 pins. Put the white bottom cover back onto the connector. Now, you can simply strip the other end of the wires and splice/add to the other wires.

5. You will need to wire:
Pin 5 of M67 to pin 6 of M66 (pin you added)
Pin 4 of M67 to pin 7 of M66 (pin you added)
Pin 1 of M67 to pin 20 of M66 (splice into wire)
Pin 6 of M67 to pin 19 of M66 (splice into wire)

6. Next you will need to wire for illumination:
Pin 2 of M67 to pin 3 of M256 (splice into wire)
Pin 3 of M67 to pin 4 of M256 (splice into wire)
Note: 6MT (manual transmission) is connector M256 and 7AT (automatic transmission) is M144 connector. Pinouts are the same except wire colors are different.
Picture: Nissan 370Z Forum - 2SIC4U's Album: Nav Conversion AC - Picture
http://www.the370z.com/members/2sic4...6-ac-m256.html

Now what no one has been able to figure out until now is get the rear defrost to work.
7. Pin 27 (pin you added) from M66 to Pin 130 of BCM. You will need to add pin 130 to the BCM which is located in your passenger side kick panel.

Note: I pulled the connector out of the BCM, carefully pride open the white door on the side of the connector and kept a small screw driver to hold it open, I also carefully removed the white bottom that covers the pins. I then slid the pin through from the bottom by forcing it in. I used a small hook tool to hold down on the inside pressure piece while pushing the pin in. This was the hardest pin for me to install. You can also use the method from previous notes above.

Pictures:
Far Nissan 370Z Forum - 2SIC4U's Album: Nav Conversion AC - Picture
http://www.the370z.com/members/2sic4...-ac-bcm-1.html

Close Nissan 370Z Forum - 2SIC4U's Album: Nav Conversion AC - Picture
http://www.the370z.com/members/2sic4...-ac-bcm-2.html

8. Pin 26 (pin you added) from M66 to Pin 9C of M3 on fuse block. This is located in the driver side kick panel. This is the upper left connector.

Picture: Nissan 370Z Forum - 2SIC4U's Album: Nav Conversion AC - Picture
http://www.the370z.com/members/2sic4...693-ac-m3.html

9. Plug the M67 connector into the non-nav HVAC controls
10. Connect whatever other wiring for your aftermarket radio, put dash back together
11. Connect battery and enjoy your new setup.

Good luck!!! My Instagram, YouTube, and Facebook names are all: AGeekyGuy

Please let me know if you were able to follow this or not. I also uploaded a video to my YouTube channel that might help.
https://youtu.be/uH7DZh0gtKE

My setup:
Picture: http://www.the370z.com/members/2sic4...ac-tablet.html
http://www.the370z.com/members/2sic4...ac-tablet.html

Awesome writeup!

I did this, works great, i even ****** up and connected wrong pins and didn't blow anything up.

Great detailed writeup.
what about converting non nav to nav? did you sell your nav unit? i will be interested to buy that and do a writeup for non nav to nav conversion :)

Excellent DIY. Nice to see some place that sells small lots of connectors (most I've seen want you to buy in lots of 100 or even 1000).

You would have to make a lot of harnesses, or find a donor car for them. Plus add the GPS antenna, shark fin antenna, sat radio module, and wire up the backup cam (which is split between 3 harnesses itself). The factory nav is garbage, definitely not worth the hassle. I'm holding onto mine for when I decide to sell the car down the road.

Navi Delete Effort Without A/C Amp Swap
 

I have an '09 Sport/Touring with the Navigation system. I liked the idea described here to convert to non-navi for custom audio installations but I am approaching it from a different angle. I am working on a way to use the base model A/C dial control module with the Navi AC amp module. This would eliminate a lot of invasive modifications to the Z to perform this conversion. For example, it would eliminate splicing into existing wire harnesses, adding pins to existing connector housings, and running new wire. It would also remove the need to source a base model AC amp (which I know isnt a huge deal, but as of now are are ~$80).

In effect, this would be a plug-n-play translator that would allow the base AC controls to operate as normal and interface with the Navi AC system. Additionally, the AC state could be communicated to an app (or custom screen) to get visual feedback. In my case, I plan on integrating a tablet in conjunction with an aftermarket stereo. The tablet could run the AC state app and provide things like Mode, Temp, Fan speed, etc, similar to what the Navi screen displayed.

Anyway, I have ordered a base model AC control module. It would be awesome if anyone had a functional base AC amp that I could barrow (or buy for cheap!?:ugh2:). I would pay to have it shipped both ways and would reimburse/replace it if it got damaged. I am just trying to avoid having to buy one off eBay and reselling it. I don't have a good idea of how long I would need it yet, so that may not work for most.

Trimmed your post so I'm not quoting everything but look into this if you don't mind eliminating the knobs:
https://www.youtube.com/watch?v=_13IPpjElL0

Yes, I have actually implemented this project and controlled the AC with my phone. I then wrote my own application that runs on Windows to further test. It does look really neat to have everything on a screen, but I actually wanted to keep tactile controls. The two main reasons for this is that it would be way easier to implement due to being able to simply buy a base model aftermarket 2-din stereo bezel instead of the added effort to make my own full console tablet bezel (or spend way more $$$ to buy something pre-made). Second, I actually really like physical controls. I tried the whole on screen environment in the Tesla and never really liked it to be honest. Sure, I would probably get used to it eventually, buy I felt like it was a bit too distracting. At least for me. The physical controls can be manipulated without ever taking your eyes off the road and that makes me much more comfortable.

Oh sh!t!! I’m doing a tablet install right now on my car, but not all that technical. I was looking at the can-bus project a few weeks ago, but didn’t know someone had an interface to go along with it!! Need to definitely look into this more as I did the dial conversion but would rather the all digital method.

edit: my progress so far. Running Brainiac and plastics from them.

I still have the Nav unit but I would have to remove a ton of other wiring in the dash to allow for the opposite to be wired but from my understanding you would have to swap the entire cars wiring harness to do the conversion from non nav to nav. The nav is all digital and the non nav is analog. This is why you can swap the nav AC to non nav as you can swap the amp and add the wires but for the digital of the nav, it interacts with the cars PCM/ECU. IE, the nav can display other information about the car so trying to go from none nav to nav would be a lot of work and require finding the correct full car dash wiring harness.

Why is it that installing a new HU will cause the defrost not to work any longer? I ask because it seems like every time I pull the battery I somehow **** something up (sent stock radio into security protection mode, got myself a nice flashing airbag light) and I just want to make sure I don't move on to disabling the defrost; it's cold in Michigan this time of year, and I need my defrost lol

Someone years ago did this conversion but never figured out the rear defrost. I was able to figure out why and my solution is posted above. The Nav system, digital AC controls, and radio are all one unit. In the None Nav version, the AC unit is analog. This is why you need to change the AMP being used from the nav to none nav and add pins. The pins are to send the analog signals that are not needed in the nav version.

This isn't entirely accurate. The Navi AC system is controlled via the CAN bus. There is an AV CAN bus that interfaces with the Navi AC/Stereo control panel and communicates to the stock HU. The stock HU translates that communication into different CAN messages on the main CAN bus that connects to the HVAC Amp.

The non-Navi controls are also digital, but they communicate directly to the HVAC Amp via a dedicated serial interface (No CAN bus). There is no analog AC control in the Z.

One of the goals of my current project is to make this conversion a plug-n-play experience with the non-Navi controls interfacing with the CAN bus system.
http://www.the370z.com/audio-video/1...e-project.html

Also, I have sourced the needed 10 position connector for the non-Navi control module locally from Mouser Electronics:
TE Connectivity - 936163-2 - $1.53 - Way easier that ordering from Japan ;)

This write-up is great. I too am doing the conversion. I just got the A/C controls working last night. Feeling good about the project.