[Guide] How to replace the factory sat nav with an aftermarket head unit

[btjtaylor]

I will stop short of producing a step-by-step guide on how to replace the head unit because there are a lot of variables and there will still be some work required to connect everything exactly as required, but I hope this information is useful to anyone attempting the same

There are loads of other videos/posts about taking the dashboard apart so I won't repeat that here

The parts I purchased:

Dash fascia adaptor:
I used AVC 381130-11
https://shop.acvgmbh.de/index.php?s...e(detail,flextor)&_edit=3222&search=381130-11
InCarTec 50-897 and other similar models available

FM Aerial harness adaptor:
InCarTec 21-118
https://incartec.co.uk/product/Nissan-06--Aerial-cable-adapter-to-DIN-radio

Adaptor for reverse camera (requires modification as the connector doesn't fit an accord):
https://www.aliexpress.com/item/1005004625021947.html
or (doesn't require modification
https://mobilemaxcaraudio.com/produ...-tsx-factory-backup-camera-retention-harness/

Steering wheel controls adaptor + harness adaptor:
InCarTec 29-679
https://incartec.co.uk/product/Hond...-Jazz-steering-wheel-control-interface-29-679

Climate control retention cable:
https://mobilemaxcaraudio.com/produ...rol-conversion-harness-navigation-to-non-nav/

ELS amplifier retention interface:
https://mobilemaxcaraudio.com/produ...cura-els-audio-amplifier-retention-interface/
Without this the factory amp is stuck at a low volume level

Arm rest USB retention cable:
InCarTec 24-251
https://incartec.co.uk/product/Honda-Mitsubishi-USB-Retention-harness-cable-24-251
or available more cheaply from Aliexpress e.g.
https://www.aliexpress.com/item/1005002503470909.html

Display screen from base model car:
Should be loads on ebay but if you are struggling search for "D099T"

Dash storage cubby from base model car:
Again should be plenty on ebay. If you can find someone breaking a base model car, you could ask them to send you the display screen, dash cubby and the wiring/connector from the display screen to splice it in yourself

Reverse light wiring

You can take a reverse light feed from the wiring in the driver's fusebox (on the right of the accelerator pedal)

The light blue wire in this area connector is the 12v feed for the reverse light, as per the wiring diagram:






Main harness wiring

This connector removed from the "Audio Unit" (CD changer) is where most of the stereo connections are made:

Here is the pinout of this connector:



The ELS module from Acura Audio Garage came with the Honda connector on so I didn't need to do too much to this.

The steering wheel control module connects to pins 5 and 16 of the Audio connector "A" (the connector above) as per this diagram


There is also a wire that connects to the connector removed from the bluetooth module in the passenger footwell (you can get rid of that as its no longer needed) which allows the answer/end call buttons to work

I had to splice these pins in to the harness provided with the ELS box as that one came delivered with wiring for another steering wheel control setup.

The factory amplifier in the boot receives a line-level signal so you need some RCA connectors on the harness (Pins A18,A19,A22,A23, as per above), to send the signal from the pre-out connectors on your head unit

The end result will look something like this (this was a previous attempt that I hacked up!)

 

[btjtaylor]

Factory amplifier control

The biggest problem with this task that I found is that the volume level was not adjustable. The factory amplifier in the boot is controlled digitally so without the factory head unit you are stuck with it at a low volume level. In the wiring there is a mention of "ELS" data which seems to be some kind of proprietary amplifier interface. The ELS interface wiring from Acura Audio Garage (linked above) was the only solution I found to this problem, albeit an expensive one

It connects to this plug that is removed from the factory audio unit

Here is the pinout I found in the service manual and how the adaptor is wired up but I didn't find any information online about how it works:

I mounted the volume control on the trim here (there is a space behind to feed the wire):

 

[btjtaylor]

Reverse camera wiring

Once you remove the top display screen you will see this connector:

This connector contains the wires that connect to the reverse camera. I purhcased the adaptor noted above and the connector was wrong so I had to chop it off and wire it up like this:

Once the reverse light feed is connected (as per above) the head unit will know when the car is in reverse, the camera will be powered from the reverse feed and the reverse camera image is displayed

I wired this up using In-sure connectors (I don't trust my soldering, especially in a tight space) and ran the cables back down behind the dash to the head unit to make the connections:

 

[btjtaylor]

Climate control display

When you remove the factory head unit you lose the ability to see the climate control information

In order to remedy this you can install the display screen from the base model, but it has a different connector.

You can use the pre-made adaptor and run it up behind the dash to the display screen area:

I did figure out the wiring from the diagrams in HDS but I didn';t actually test making my own adaptor:

 

[btjtaylor]

USB port in arm rest

This is fairly straightforward - the adaptor cable (mentioned int he first post) above connects to the plug on arm rest like this and gives you a standard USB connection you can plug into your head unit. Once this is done the arm rest USB works as normal

I gave this area a thorough clean afterwards for obvious reasons !

 

[btjtaylor]

FM Antenna

This connector behind the dash is used for the FM aerial - just connect the adaptor (it needs a power feed too but you can take that from your head unit's wiring, typically) and away you go

And finally, here is the finished article!

 

[btjtaylor]

Acura Audio Garage have released a video that explains a bit more about the ELS interface here - good if you want to some background info about this topic:

2009 2010 2011 2012 2013 Acura ELS Audio Amplifier Interface | Aftermarket Radio Factory Amplifier (youtube.com)

 

[Nathjkent]

pfffffff F that

 

[btjtaylor]

One of those jobs where about half way through you regret your decisions but you're in too deep... the wonders of modern car infotainment systems!

It was a good sense of accomplishment to get everything working but from a value for money standpoint it was a massive fail

I think for most people a USB-powered AUX Bluetooth dongle and a phone holder will suffice, at probably about 50 times less the price..

 

[Nathjkent]

Yeah, i have one of those plug in AUX cables, cost me about £15 and took about 10 mins to install
still, yours looks cool. well done

 

[Trawa]

I must be the only person who actually likes the stock infotainment system lol. My only gripe with it is the stock head unit turning down bass at high volume which is pretty damn annoying if you listen to rock or metal but that can be fixed relatively easily with a custom EQ preset on your phone.
Great write up, congrats on pulling it off.

 

[btjtaylor]

I must be the only person who actually likes the stock infotainment system lol. My only gripe with it is the stock head unit turning down bass at high volume which is pretty damn annoying if you listen to rock or metal but that can be fixed relatively easily with a custom EQ preset on your phone.
Great write up, congrats on pulling it off.

Hah thanks - it's a good sounding system which is why I was keen to keep the amp rather than rip it out but I wanted to have a more up to date Sat nav which I like to have especially if you end up in a place with no signal, and I missed the DAB radio from my last car. I don't use it a huge amount but it's nice to stick on when you can't be bothered to find something on your phone, for short journeys etc.

The bass reduction you mentioned - I've not noticed that to be honest - hard to say if it's the head unit or the DSP in the amp doing that - unfortunately I've lost access to the tone/balance/fader controls of the factory system now although I can obviously do an EQ in my head unit instead. I don't think I've ever needed to adjust balance or fader on a car audio system other than troubleshooting blown speakers once but I can see someone might want to if they have kids in the back, maybe (grasping at straws)

It sounds good to me thats the main thing

 

[Hondoob]

Thanks for the brilliant guide, really appreciated. One day I hope I'll get round to emulating this.