2015 to 2016 Leaf S Radio Swap DONE: the lengths I will go for OEM Bluetooth streaming

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chumpp

Member
Joined
Apr 30, 2017
Messages
18
How I put a newer, better, bluetoothier OEM Nissan Stereo from a totally different car in my '15 Leaf and got EVERYTHING (yes, everything*) to work.

Old & busted:
YNZaBiJ.png


New hotness:
ysaMKuK.png


Story Time
(If you want to skip all the story, just click here to go right to what I did)
At the end of 2015, we bought a new Leaf S for the Mrs; she loves the car, but somehow, Nissan felt it was appropriate in TYOOL 2015 to sell a car that can't stream music over Bluetooth. Unacceptable. I wanted to do something about it (I had just replaced the radio in my Forester XT with a new Pioneer double-din unit) but after an incident involving cursing, blood, a blown fuse and a semi-significant amount of smoke, she didn't trust me. Fair enough. I bought her a little $18 Anker (or Aukey?) Bluetooth dongle from Amazon and didn't think anything more of it.

Thing is, I don't drive the car often, but when I do, it's with my wife, so we are usually talking and not listening to music. Turns out, that thing is super flakey, and moreover, there is often a contention between that thing and the car bluetooth over which device gets to take calls if they come in. It had gotten bad enough that she would either 1) not listen to any music in her car (because lol radio sucks), or, 2) spend 10 minutes un-pairing/re-pairing with the adapter in the car before she could drive. To make matters worse, in November 2016 her mum was excited by my wife's Leaf and decided she'd get one of her own - a 2016 Leaf S. And lo and behold, the 2016 Leaf S *does* have Bluetooth music streaming. That last piece was the nail in the coffin. I was going to do something about it.

I parked the cars side by side:
k2Ttj3f.jpg


As far as I could see, the dash was identical. It literally looked like both the cars were going to be exactly the same under the dash - other than what radio they were attached to. Just to be sure, I pulled the radio out of both of them to check the wiring:

2015 Leaf S Accessory Connection:
DnOImX9.jpg


2016 Leaf S Accessory Connection:
OAPTbBk.jpg


Hmm; looks almost identical - but there are three pins that have moved from holes 11, 12 and 13 of the top row to pins 14, 15 and 16 of the bottom row. I bet I just have to move those pins, and it'll work, right? At the time, I didn't notice the extra two wires going in to pins 5 and 6 of the top row. Whooops...

I went to Car-Part.com and searched for a replacement radio for a 2016 Leaf S. None found - - however, apparently the Display Radio from the 2015 Sentra was compatible. An auto recycler near me had an ad not unlike this one:

y4bDNdD.png


and the radio was just $80!. Sweet!

The radio came in the last habitable day outside before the winter set in, and i tried fitting the radio.

Here's what worked:
*Device powers on/off with vehicle
*Most non-Bluetooth music sources (CD/AM/FM/XM)
*All speakers
*Backup camera

Here's what didn't:
*No AUX input (used to be on the radio itself, moved elsewhere in the car for '16, plus, I didn't get an adapter
*No USB input (different plug between '15 and '16)
*Limited steering wheel controls (Volume/Source buttons worked, but not phone up/down)
*No microphone, and, as a consequence
*No possible way to pair Bluetooth

No matter how hard I tried, I could not get the microphone to work.
Defeated, I put the old radio back in, and tried to plan what I'd do once it was nice outside again.
 
So now it's Spring, and I can stand to go outside. I got an idea that rather than try to pull the wiring harness inside the dash apart, I'd just get a male-female harness extender, and make the changes I needed with that. I bought an AX-NIS-ADDCAM1 harness adapter, pulled all the wires I didn't need, and got to testing. Here's what that looked like:

XID0ycS.png


Eventually, I discovered the phenomenal resource of nicoclub.com - a site with service manuals for (almost) all Nissan cars. Their link to the 2015 Leaf page was broken, but I figured the biggest changes (radio-wise) must have happened between 15/16, and less from 14/15. I used the Leaf service manual for the 14 to see how my car was wired, and compared the service manual from the 15 Sentra to see how the new radio fit in. Ultimately, what it comes down to is this: the 2015 Leaf S has all the bluetooth junk in an entirely separate module - in the trunk, whereas the newer radio has everything internally. If I wanted to get the newer radio to work in my car, I had to bypass the bluetooth control unit. This meant pulling the whole damn trunk apart. F#$^k.

So here's what I did (all pin numbers refer to the diagram on Nicoclub's Service Manuals):

Wiring Harness Adapter: I routed the mic input signal (formerly at pins 24 & 25) to their new location on the new radio (pins 50 & 52)
I also ran a new wire to the trunk (probably could have used an existing pin, whoops) to carry the +5v from pin 51 to power the Mic. This wire was connected to Pin 29 of the Bluetooth Control unit harness. I ran all the other wires that were present on the vehicle's harness straight through, and discarded the wires that weren't present.

Then, I just jumped two sets of two pins together on the harness - pin 7 to pin 9, and pin 8 to pin 10. In this way, the microphone signal goes from the roof down to the trunk, into the harness, through my jumped pins, and straight back up to the harness that connects to the radio! Inefficient, but functional! I tested my theory, and lo and behold, the mic worked! I was able to pair my phone (since I could finally say "yes" when it asked if the pin on the handset matched the pin on the display). I put the car back together while listening to some music, then excitedly texted my wife and asked her to call me. She did, and so I pressed the "Call Answer" button on the steering wheel. Nothing happened.

F!#@$%!%#&&
 
THE PLAN
Here's what I did. You can try it too, but I'm not responsible if you damage your stuff or burn things. Please be careful. I don't provide any guarantee that this won't destroy your car, kill your dog and everyone you've ever cared about. But it worked for me, and while I still have a wife, we never had a dog.

This is the summary of what I'm doing to the Bluetooth Control Unit Wiring Harness - after it is completely disconnected from the Bluetooth Control Unit. As for the unit itself, I'm going to take it out of the car entirely, because it's another ~16 ounces to carry, and who knows, maybe that's another mile of range. Or at least a few hundred yards?
jSdPKwi.png

In short, I bridged the Mic Input + to the Audio Out + (same for the "-"), bridged the Steering Wheel Control wires in a similar manner, and provided 5v+ to the Microphone, which was not getting 5v from the BCU any longer.

Now, last time I pulled the car apart, I didn't take any photos. But this time I did.
If you want to do this, you're going to need
Components
*A Display Audio Unit from a wrecked 2015 Sentra (you can source from a wrecker, eBay, or Car-Part.com
*An AX-NIS-ADDCAM1, wired as described above (mic input signal (pins 24 & 25 on male end) to their new location on the new radio (pins 50 & 52) plus all un-used wires removed. The ADDCAM harness has a RCA plug that I didn't need so I removed it; I may have had to move some pins around but I don't remember. You will be able to figure this out easily when you're checking the "straight through" part of the harness. I also ran a new wire to the trunk (if you have a multimeter you could potentially try re-using the old "AV COMMUNICATION HIGH or AV COMMUNICATION LOW" pins which aren't used any longer) to carry the +5v from pin 51 to power the Mic. This wire was connected to Pin 29 of the Bluetooth Control unit harness. I IMPLORE YOU TO DOUBLE CHECK MY PIN NUMBERS FROM THE SERVICE MANUALS (2014 LEAF & 2015 SENTRA - select "AV"), AVAILABLE ON NICOCLUB, BEFORE YOU WIRE THIS STUFF UP!

Speaking of checking pins, you'll see this illustration all over the service manuals:
jbUFssP.png

What this means is that pin numbers are counted as though the pin is connected to the device - that is, you are looking at the cables going into the plug, with the pins pointed away from you.

Tools
*A philips-head screwdriver
*Either of the following:
-A method to remove pins from the wiring harness (I used a T-Pin, which you should nick from someone's office cubicle because they probably come in boxes of 1,000), or
-a soldering iron and wirecutters
*Patience
*A spudger/plastic pryer (to remove trim)
*A socket-wrench (or other wrench-like thing) and 10mm, 13mm, 16mm sockets. 10mm is optional if you want to remove the BCU, but you can just leave it there, disconnected and skip the 10mm
*A multimeter is handy

I strongly recommend you keep the Nicoclub Service Manual handy for instructions on removing trim, or referring to if you have questions about the wiring. it is a thorough pain to remove trim under even the best circumstances, and these manuals help to understand just how to do it.

UPGRADING YOUR STEREO STEP 1: Remove the rear seats (yes, seriously).
sf9gMdj.jpg


Once you've got the seat base up, use your 13mm socket to remove the seat back sides (lol):
PmEBTqp.jpg


...and your 16mm socket to remove the seat back base (bronzey-colored bolts in the center).
See those two wires on the left? I think they're part of the charging circuit. Good Lord don't damage them.
a83dphV.jpg


Be careful not to pull the seats all the way out of the car - moving the seats just a half foot forward meant I didn't have to disconnect the seat heaters, which is one less mistake to make putting things back together again.

STEP 2: Access the Bluetooth Control Module (a.k.a. dead weight)
The reason we needed to get the seats moved was because their presence prevents you from removing the rear side interior trunk panel (U.S. passenger side) and thus, the BCU. Before you can get to that panel, though, you need to remove the rear inner trunk lining: two little push pin things hold it in place.
ZgSC5rD.jpg


With that out of the way, you can finally remove the panel blocking the BCU. As you get it loose from the wall, disconnect the little luggage lamp.
pgZU778.png


Here's the BCU, as I left it last week - with functioning telephone & bluetooth streaming - but no steering wheel controls.
This is it with the jump made between pins 7 & 9, and pins 8 & 10.
r2HEXRX.jpg


Time to remove all that tape and do some testing of the theory I penned above.
Remember: Safety is our #3 goal.
81grn94.png

Looks like crap but IT WORKS!

Shall we tidy it up a little bit?
CoaU3eQ.png

Good enough for me. Let's ditch the BCU & wrap the harness in a quarter-roll of electrical tape.

T6Arkkd.png

Done.
Installation is the reverse of happiness.
 
Lessons learned
First, if you fail to plan, you plan to fail. It was dumb to buy a new radio on the basis that the two cars had to be the same even though their radios clearly weren't. The one part that I did plan in advance was the harness adapting the new radio to the old wiring - and that was the one part that worked first try. I did run the +5v through some doorbell wiring to the trunk (that's the red wire) and put it into Pin 29 - but in retrospect, I could have used an unused wire to deliver the 5v (like either of the two in position 5 & 6 of the top row that aren't present on the new radio).

If you want to try this yourself, first, please read the service manuals. I have a Subaru that I have to pay for access to manuals like these, which sucks, so take advantage of this incredible resource. I guarantee I would have given up without access to the manuals and documentation on what each pin does.

I could have put in an aftermarket radio, sure, but this one just looks "correct" for the car, it doesn't look aftermarket, and it works flawlessly*.

Oh right. I did put an asterisk above - where I said I got everything* to work. Here's what's missing, and more importantly, how it can be fixed.

*USB: The USB port on the new radio isn't the same as it was on the old radio. You'll need an adapter to make it fit. The old radio used a proprietary connector, whereas the new one uses a USB Mini-B female connector. Match the two up with an adapter and you're set. Not a big deal for us because we never use the USB, so we probably will ignore it.

*AUX-in: The old radio had a 3.5mm AUX input directly on the front of it - but as the screen's a bit larger now, there's no more room for it on the device. In 2016+ Leaf cars, the aux input was moved somewhere else. So if you need an AUX, first you'll need an adapter to get a 3.5mm input to connect to the radio, and then you'll need to put it somewhere. You could probably just order the OEM part from Nissan directly, to be honest - same for the USB - but don't expect it to be cheap.
 
cummpp Pretty good info. Did you take any video to upload to YouTube?

Any ideas on how to connect a steering wheel control interface to the Bluetooth Control Unit Wiring Harness?
 
Can you give some input on this thread, please: http://www.mynissanleaf.com/viewtopic.php?f=36&t=16061&start=30
 
Where does the Microphone 5V plug in? The service manual mentions connector R3, terminal 4 but no schematics are shown.
 
chumpp said:
STEP 2: Access the Bluetooth Control Module (a.k.a. dead weight)
r2HEXRX.jpg

...is that entire metal box dedicated only to bluetooth??? Or is it just the black box affixed on the outside?

If it's the entire box, that seems....kind of excessive
 
Hey all;

Sorry for the late reply; I didn't see anyone ask any questions for a while so I stopped checking the thread.
Let me try to answer your questions:

Fmerc said:
cummpp Pretty good info. Did you take any video to upload to YouTube?

Any ideas on how to connect a steering wheel control interface to the Bluetooth Control Unit Wiring Harness?

I didn't do a video; but I don't think there would be much it would add; other than the misery that was pulling half the car's interior apart.

As for the SWC interface; you mean for an aftermarket kit, yeah? If so, I imagine it would depend on the kit, but if it's anything like the Axxess kit I put in my Subaru I imagine you'd just wire it up to the pins which are indicated as coming from the SWC and going into the BCU - those being pins 14 (common - ) and 12 (LAD IN 1+) and 13 (LAD IN 2+). But now you have to run the adapter from the trunk. Thing is, if you're using a SWC interface you're probably using an aftermarket head unit - I would want to intercept the controls closer to the stereo.

Aftermarket or not, I would just the same thing I did and use an adapter harness to turn the connector into a '15 Sentra - that is, my adapter harness and the jumped leads at the BCU just turned my car into a 15 Sentra as far as the radio is concerned - so any aftermarket head unit that's compatible with the 15 Sentra would work in my car now. If you look at the aftermarket options for a 15 Leaf on Crutchfield you'll see barely anything - but there are many more for the Sentra.
 
Fmerc said:
Where does the Microphone 5V plug in? The service manual mentions connector R3, terminal 4 but no schematics are shown.

Which end do you need clarification for; the radio end, or the BCU end?
 
kidjan said:
chumpp said:
STEP 2: Access the Bluetooth Control Module (a.k.a. dead weight)
r2HEXRX.jpg

...is that entire metal box dedicated only to bluetooth??? Or is it just the black box affixed on the outside?

If it's the entire box, that seems....kind of excessive

The massive steel box (not just the black bit) seems to be housing only Bluetooth, and yeah. It seems pretty silly. The BCU has been sitting on a shelf in my garage since the stereo swap and nothing else seems to have changed. I'll post if I notice something else... but yeah.

Maybe it had something to do with the XM? I don't know, we don't have a satellite subscription so I couldn't say - but we still get the test station with the updated radio so unless that maybe housed an XM antenna also, I got nothing.
 
Fmerc said:
Can you give some input on this thread, please: http://www.mynissanleaf.com/viewtopic.php?f=36&t=16061&start=30

Looks like the bulk of the folks posting in that thread are looking to replace the stereo with a non-OEM device, which is cool - I'd strongly recommend that anyone doing that sort of thing who doesn't want to cut/splice any of the harness cables for a '15 or earlier car use the BCU bypass and harness adapter I have listed in the third post of this thread - doing this will give you a harness for a '15 Sentra which opens up your aftermarket options a bit. Again, please do any of this at your own risk, and at all times refer to the service manuals if in doubt.

I'll go out to the Leaf this afternoon when the Mrs gets home and I'll yank out the harness adapter I made to get some pics, and will detail what's connected and where for that particular piece of the puzzle.

e: gonna have to wait for the weekend. Will get a pinout together of this harness adapter.
 
Here's the modified harness as described in my third post - it's based on an AX-NIS-ADDCAM1 harness adapter - but slightly modified.
The Black and Yellow wires wrapped around the harness are a part of the harness adapter and are not used at all - I could have cut them off but I'm planning on using those for another Leaf modification later ;)
Df9teFW.png


Let's get a closer look at the connections:
58xQ5AI.png


In this angle, I have the female end (the end that the male connection from the car plugs in to) at the bottom, and the male end (which plugs into the stereo) at the top.
Let's start with the top row of pins from the male connector (to radio) in the top half of this picture. There are six wires which are connected 1:1 - that is - they go from the same place on the car's harness to the same place on the new radio. Other than the 6 pins connected at the leftmost connection on the top row, the entire top row is empty as it connects to the new radio - but not so on the female end which connects to the car (bottom half of this picture). Although the 6 pins are present - there are another two pins (green/white and blue/black) occupying that row as connected from the car. These are carrying the MIC+/MIC- and need to be moved to their new location - this happens to be on the second row.

Here's the second row:
CmrH0P7.png

Now, this is a little confusing to look at, because these connectors aren't really "side-by-side" like this in real life - so the connections are flipped. The left plug is the female (to car) and the right is the male (to radio). You can see where the green/white and blue/black connections are coming from the car (left half of image, top row, left) - and now where they're going to (right half of image, bottom row, right). In between those pins there is a red wire - this is the +5v output from the radio which is providing the mic power through a long wire down to the BCU harness.

If you refer to the images in my first post, you'll see that only 4 of the top row pins are probably needed (as the old radio had 6 pins and the new one only 4). This would mean you could possibly use the existing wiring from either of those two pins (the old radio used them for COMM high/low to the BCU, now removed from the car) as your method of delivering +5v Mic Power to the trunk - saving you from doing what I did and running a new wire to the trunk. I don't know if you might damage anything running current through those wires - obviously only try this (or anything I posted) if you are willing to take the risk of damaging stuff - but hypothetically, what you'd do is move one of those two spare pins from the top row between the green/white and blue/black in place of my red wire, which runs to the trunk to the BCU harness, and then patch that to the Mic Power input.

More pics later!
 
Here's a decent shot of the connection which is going into the radio, with the red +5v doorbell wire I ran down to the trunk.
That red pin at the bottom right of the radio end is (as far as I know) the easiest +5v output to get at from the radio itself.
There are 4 other pins on the bottom row which will be a 1:1 connection.
MYlI2WZ.png


Here's a view of the top row, side by side
C8f8UVB.png
 
Someone asked about the Bluetooth Control Unit, and was asking if that's all it does.
Let's find out:

The unit pulled from the car
rOFWVcX.png


Connections on the device
cMA7flb.png


Black box pulled off the top; looks like this particular component is for comms between the device itself and passenger's phones
0zFX2ph.png


Hell of a lot of silicon for a basic bluetooth module..
NRUw9SE.jpg


I see a Texas Instruments OMAP processor, some memory of some description just underneath and to the left of the OMAP chip, beneath all of this is the Bluetooth radio ("csr" labelled chip, upside-down). The square chip on the right is another TI processor (TMS 470).

Let's take a look at the sheet for the OMAP chip:
http://www.ti.com/product/OMAP5912

What the hell is this thing for?!? That is a hell of a lot of power for just handling phone calls!
I did bench test the old radio - it still does "radio" stuff (obviously though it never streamed Bluetooth) but since just about everything else seems to work, I'm perplexed.
 
That....is really weird. I don't understand what all of that hardware is for; also, that TI chip has really bizarre stuff like a DSP core that includes video stuff (???). I'm also baffled why this thing has to live in the trunk???
 
It's kinda big - like, the length of a VHS tape and twice as thick (with the brackets attached). They may not have had room for it behind the dash.
 
I don't understand that either; plenty of companies fit full-featured bluetooth capabilities in a form factor dramatically smaller than that. Or, translation: if nissan made a blue-tooth enabled cell phone, it'd be twice the size of a VHS tape???
 
This thread was immensely helpful and I want to thank you for documenting this process :D

I have a 2013 S Leaf that I swapped a Pioneer NEX HU into and just went the last mile to get the telephone steering wheel buttons working and better mic placement. I posted about it over in this thread.

One thing to note is if you're using the mic that came with an aftermarket head unit, you don't have to worry about getting 5v to the mic. Just wire it through and install the mic in place of the OEM one.
 
Chumpp and others:

Great work and persiverance!

Has anyone else performed this install/change?

1. After round 2 of your install on this thread the only things that were not working was the USB and aux connection because the plugs were different?
2. After you did all the wiring and removing Black Box. The BT streaming and phone and all the steering wheel controls worked?

I want to upgrade mine, but dont want to use an after market deck. Prefer this route if possible.
Thanks,
Chris
 
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