Finally got the 2018 navigation radio working in my 2017 Yellow. Although I hear there are a lot of complaints of this navigation receiver it is 100% better than the 2017 radio. If you were to go buy all the parts new you would be looking around $2,800. Plus you are not able to buy the connectors. Subaru sells the entire harness not just the connector and pins. As the 2018+ with navigation become older and more of them are totaled this option could become an inexpensive way to upgrade. Few people look to buy a stock radio so junk yards usually sell them inexpensive.
This should work for 2016, 2017 and 2018+ premium models.
Benefits of this route.
Retains stock look. This is important to me. I like to modify my car but try to keep it from looking that way.
Inexpensive, If you can find a totaled one close to you.
Easy modification.
Cons of this route.
Will not be as functional as an aftermarket option.
First thing to do is to find a donor car that they will let you cut the wire harness. Items you will need listed below.
Navigation receiver.
Plastic trim that goes around the radio.
USB jacks and wire harness that it is attached to.
Aux unit assembly. This is a small black box attached to the bottom of radio.
GPS antenna. This is mounted just above the radio to the left.
Steering wheel controls.
You will want all the plugs that plug into the receiver. I would cut them with as much wire as possible.
You will also want to look at the microphone assembly and the possibility of changing this out. I was unable to do that however the receiver will work with the older one without modifications.
MIC wire diagram
Steering wheel wire diagram
The next step is to remove those items from your car.
Items to install without modification.
Steering wheel controls.
USB plugs and wire harness.
GPS antenna.
Modifications to the wire harness.
Aux unit assembly will need power and ground.
Power will go to pin 5. I pulled this from pin 3 from the 28 pin connector.
Ground will go to pin 1. I just made a short lead and grounded to the radio chassis.
Aux unit wire diagram
Rear view camera will need to be moved from the 28 pin connector to the 5 pin connector.
Pin 12 will go to pin 3.
Pin 11 will go to pin 2.
Pin 20 will go to pin 1.
Pin 13 will go to pin 4.
Rear camera wire diagram
Amplifier remote on.
You will need to move Pin 9 from the 28 pin connector to pin 8 of the 10 pin connector.
AMP remote on wire diagram
On the new receiver it shows an Ignition circuit going to pin 1 of the 28 pin connector. I have tried this connected and unconnected and not sure what this changes.
On the new receiver there is a ground supplied when the door is opened. This is on pin 4 of the smaller 12 pin connector. This is for retained accessory. I have not hooked this up the radio will run for around 2 min after you shut off the car. Not positive I will ever install this.
The microphone assembly on the 2018+ appears to be better quality. It has 2 microphones built in. I did not have a close donor car and was unable to see if changing this out was an option. However the 2017 microphone works with no changes.
I would show you pictures of the modified wire harness only I purchased the radio from a junkyard in Houston. Once I got the radio I was unable to talk them into getting my any other components so I ended up buying parts new and had to hack the wires into the new connectors. I will keep an eye out here in Dallas for one and see if they will let me come and get the connectors then I will be able to modify it so it looks a lot better. (Yes I worry about how something looks that no one else will ever see)
If someone gets to a new one and sees anything else let me know. I will update this.
Connector list