Carplay Upgrade for VW Touareg

I recently inherited back my 2015 VW Touareg after my wife has driven it for the last 4-5 years. I’ve come from a car with Apple Carplay, and the thought of losing it made me un-happy, going back to old school Bluetooth and no Nav (never got it switched over from UK when we got car). If you’re used to Carplay, its definitely a step back in time.

So I went on to AliExpress and brought a Carplay module that’s meant to add Carplay feature to the RNS850 system in our VW Touareg. First unit I ordered wasn’t compatible and I had to refund and get another unit –

This is the one I ended up ordering for my car and installing – 2015 Touareg 3.0TDI R-Line (ex UK).

New Apple Carplay & Android Auto Retrofit For Volkswagen Touareg Rns850 Audio From 2010 To 2017 Vehicles – Car Multimedia Player – AliExpress

Unit arrived quickly (10 days to NZ). When i opened it, I was a bit hesitant once I realised I had to splice in to factory wiring to get the unit to work, I had assumed it was going to be like a plug and play connector for the back of the stereo, but there’s a bit more to it than that.. :-/

That’s when I started looking up how others had done it and trying to piece together a start to finish install with all the bits collected.. and i thought might as well capture it for the next person like me who wants to add the feature to their Touareg.

I found a forum on Club Touareg’s site with a lot of people talking about the downsides of the unit and installation info (as the info provided by the supplier is pretty average.. they point you to a video but it’s definitely light on some details!! A lot of confusion around lack of instructions etc.. i read all the pages and gleened the relevant install notes in to one list (bottom of post).

I’d already brought the unit and waiting for it to ship, so I didn’t want to have to send back and admit defeat just yet…

Big thanks to everyone who contributed in this channel – it was several points reading through here that prepped me for what to expected

JoyeAuto – Apple CarPlay RNS 850? | Club Touareg Forum

On the whole, the unit I think does a pretty good job. I’m stoked to have this functionality in a 2015 car I will be driving for a while – and Wireless Carplay is even better than what I had in a later model Audi with plug in cable Carplay. With new unit, you get in the car and its just there and connected without having to touch phone.

The unit is fast to respond, and doesn’t feel laggy (like an earlier aftermarket Carplay unit I had in an older Audi..). Some of the things covered in the forums like no steering wheel control seem to work for me, so maybe be fixed on this 2022 unit?

Steering wheel control works fine, the audio works fine through the RNS850 AUX in (although you definitely need this part below MMI AUX cable – luckily my car came with one). If you don’t have one, you will want to get one too, or you’ll have to use existing Bluetooth connection for your audio. OCR 6.6ft AMI MDI MMI AUX Cable Audio Music Interface Adaptor 3.5mm Jack Aux-in MP3 Cable for Audi Audi A3/A4/A5/A6/A8/Q5/Q7/R8/TT, VW Jetta Passat GTI GLI CC Tiguan Touareg EOS Golf Mk 6, etc. : Electronics

I also ordered some VW Stereo removal keys after watching videos and getting notes.. AUDI BMW VW FORD Stereo Removal Keys (1 Pair) | Trade Me Motors

…And POSI TAP connectors (which are my new favourite things, that allows you to tap into a wire in the car without having to cut into/solder etc.) Perfect as you have 5 wires to tap into for this install. 12v Power, Ground, MMI Read (pin 10 on back of RNS module), CAN High and CAN Low (tapped into wiring that’s in a cable tray under passenger carpet. This i thought was going to be the hardest, but it was actually one of the easier steps..

Posi-Tap Red-Grey (20-22 gauge) [PTA2022] – NZ $1.30 : FastBikeGear, Importers and Distributors of Motorcycle Accessories

So.. here’s some videos that helped with the process.. and some of my notes on the install.. I also ended up getting emails from the vendor with diagram and user manual.

My August 2022 Install

Start with tray above screen. One screw and holder in front, must pull both out for tray to come out. Pull up at front first then the whole unit comes out.

Exposes 2 screws that hold LCD in. Undo these 2 and pull unit out towards you.

Glove box removal next. I found this the easiest way to get space to get to everything. I’ve got a 360 camera box installed a few years ago tucked up behind glove box too so I think this made way easier to figure out where all the wires go with the whole big unit out the way.

Take passenger side fuse box cover off.

4 screws along top inside front of glovebox. 2 down the bottom.

2 underneath

Note: glovebox is heavy, and if you just undo screws and let it go, you’ll break wiring, lights etc.

Put a box/crate or something in the passenger side foot well to hold the weight of the glove box assembly as you undo the screws.

When you undo all the screws, let the glovebox drop down a little bit on to box to take weight so you can get to and undo all the plugs.

1. Glovebox light

2. Footwell light

I didn’t get a picture, but its at the bottom of the whole glovebox unit, and if you don’t remove, you rip the temperature sensor out of the passenger side air vent.. at first I thought id ripped the actuator out of the passenger airbag, and I felt sick at how much that was going to sot me to fix.. but then I realised the connection for airbag is in the middle of car on the other side, and what id pulled out was a temp sensor for the air vent.. it clipped back in to the duct that goes to passenger air vent.. phew!!

3. Airbag switch

This plug was tricky to remove as there isn’t much play in the cable, and the release clip is on the other side you cant see right up against the glove box. I used a car trim tool to push the clip release.

With the car still connected to glovebox with RNS850 module loom, reach in behind glovebox and unplug the RNS connections. Not any easy task – use car trim removal tools and just be patient.. Once you get the main connector out, you get a bit more space to work.

With all wires disconnected from Glove box unit, pull the whole glovebox assembly out.

Use stereo removal keys to pull the RNS850 brain out of the glovebox housing.

Sit the RNS850 on the floor and plug the connections back in. 

Note: if you turn ignition on now, you’ll trigger the airbag fault as the switch isn’t plugged in.  I’d actually been here before so just decided to let it activate (as I wanted to carry on and test everything), and would clear it after with an ObD scanner. OBDeleven

If you don’t have an easy way to reset the airbag fault by powering up with the switch not plugged in, you may want to think twice about doing it this way. Personally, I wanted to test all go before i pout all the panels back togther.

With everything plugged back in, the RNS850 should operate as normal.

Next step, splicing into the wiring.

This part worried me the most, as I didn’t like the idea of cutting/soldering on to factory wires. Enter the POSITAPs. I saw them mentioned in the club Touareg forum, and found a supplier here in NZ and ordered. You need 5 in total, i got a couple extra. There are 2 different wire gauges to get – Gauge 20-22 for MMI blue wire and CAN High/Low and 16-18 Gauge for 12v, Ground etc

The literally just twist on and tap the wire, easy to remove without damage and good solid connections.

I read differing reviews on wiring, but this is what I did and had success:

Pushed little clip to remove the green plug from the rns850 plug. Push tab and green plug pushes away.

Put the supplied loom in place and connect factory green plug to other end of short loom. This one taps the audio AUX in and is terminated with a 3.5m headphone connector at other end.

Using a positap, connect blue/orange wire on RNS850 connector (pin 10) to blue wire on Carplay module harness.

I had a third party 360 cam system and I tapped yellow (12v) and ground from here.  I believe other reviews tell you where else you can tap 12v.  My 360 camera thing had its own yellow wire to the fuse box with its own fuse – so I piggy backed this for 12v and Ground.

You don’t need to connect the red. Some people say you need to, but I didn’t with the above AliExpress unit. The way I read it, the red is to power cameras?

So only three wires to connect on harness (plus the CAN plug/socket).

So with blue, yellow and black connections done, next was the Canbus connection.

I went for under the passenger carpet method as everyone else had success. It wasn’t as hard as I thought it might be, especially with positaps.

Pull the side moulding off. I think a clip broke but I got it back in later okay.

I held the carpet up with a box as it’s hard to hold it out your way and do anything at same time.

Pop the clips on the side facing you on the wiring tray. Price it up and put something in there too to hold the case out of your way.

Find the orange / orange-green strip wires. This is Can high and low.

Using positaps, connect the extension can cable from the harness to here. Orange/green to orange green.

Close it all up and run the wires up behind glovebox.

The carplay module ‘interrupts’ the LCD connection between back of rns850 and the lcd screen module.

I found that interrupting the LVD cables at the glove box module end just gave me a black screen.  Initially I thought I’d got wiring wrong as nothing came up, but the Carplay box did have a blue flashing led on it so I knew it was getting power..

I ended up popping the connector off at the LCD screen end and interrupting with the Carplay module, and success!!

I plugged the 3.5m plug from the supplied mini harness with green plugs on each end into the socket on the main Carplay harness.

Also plugged in mic and ran past back of glovebox and up passenger A pilar to the middle where rear vision mirror is.. believe you can get the mic up in to the central top area where internal light is but havent looked into yet…

Powered up, gave things a test and all was good!

I had read in forum already about having the center console MMi Auxiliary cable. I now see why this was needed.

So the carplay unit gets its audio to the factory system via AUX in. But, the RNS unit is clever and greys this option out in the UI if you don’t have a MMI to aux cable plugged in. 

Luckily our Touareg came with one as well as an old iPhone pre lightning connector cable. I plugged that into center console, and under Media, AUX option lights up and you can select. This allows you to hear audio from Carplay module.

Other option is to do all your audio through existing Bluetooth RNS850 connection, but it’s nice to have hard wired option too. You do have to one time go in to MEDIA > SOURCE > and set TO AUX from Bluetooth. I haven’t had to go back to this. When Carplay unit is active, it remembers this option and audio goes through AUX in instead of Bluetooth. In fact, i’ve ‘un-paired’ my iPhone form the VW’s RNS so it connects automatically and directly to Carplay every time I get in now.

All in all, I’m impressed, it exceeded expectations. I had an early version of a Carplay box in a 2012 Audi, and it was slow, would often just reset, and felt laggy. Audio would break up if it was doing maps etc. Really frustrating as it wasn’t cheap.

On re-assembly, remember to connect the A/C tube for the glove box cooler along with the other connections.

I used OBDeleven tool to scan and clear the Airbag fault id triggered by powering up with the switch disconnected.


This box is fast, responsive and audio is great. It boots fast, wireless Carplay connection is fast. Audio doesn’t break up. Steering wheel buttons work. NAV button and steer wheel hamburger button switch between RNS850 and Carplay quickly.  The touchscreen on RNS850 does need quite a solid push, but it always has… not the Carplay modules fault.  The middle selector rotation knob also works with the UI which I’m used to using like in Audi Carplay.

The only button that doesn’t work is the voice command button on steering wheel.. that triggers the factory assistant system (which is kind of hopeless in NZ without been online). But I learnt if you press the bottom home/split screen button bottom left corner of Carplay, that invokes Siri the same way as a button on wheel would.

I’ve run the mic around to where factory one goes around side of windscreen, need to finish off and mount, but quality of car kit audio seems okay.

All in all, it’s great to have maps, Siri, Apple Music etc at fingertips. I’ve come from a car with all this and got very used to.. coming back to drive the Touareg with no smarts was a pain… (first world problems).

Definitely worth the 2-3 hours of pulling apart and putting back together again. 

Definitely helped for me to wait until the Posi-Taps and stereo removal keys had arrived before getting stuck in. Posi-taps are the business for anything automotive.. you can just remove them and the wire has a tiny pin prick hole but stays intact. No soldering or trying to insulate the joins.

Modern entertainment on!