2007~2015 Aftermarket head unit in CX-9 Bose system

jschwartz6

Member
:
USA
:
07 MZ5; 08 CX-9
Searched the forum and didn't get a direct answer for what I'm looking for...
I want to replace only the factory head unit in my 2008 CX-9 with an aftermarket unit and a steering wheel control adapter. It currently has the 10-speaker Bose CD changer without nav. A local reputable car audio chain store said don't replace the HU unless I do the entire system (speakers & amp too) because replacing a single component will mess up the sound. Believable, but I wanted a second opinion. I just can't afford to replace the entire system.
I reached a Crutchfield advisor and they said actually yes, I can put in an aftermarket head unit, the wire harnesses will connect it with the factory amp and all the factory speakers will work fine with appropriate power levels etc.

I'd like to verify, have any of you put in an aftermarket head unit to the Bose system, left everything else stock, and all worked out well? I'd be getting a good quality unit such as Kenwood.
If so, any pointers or trouble spots? (I've previously replaced head units in three other vehicles with 4-6 speakers and no amps or subs).
Thanks!
 
I did put in a Crutchfield BOSS unit on my 2012 GT with Bose and it works perfectly. I retained my steering wheel controls as we as the OEM rear camera. In fact, the back-up camera has better resolution now than the original unit.

The install was relatively straight forward and Crutchfield support was excellent.

If you search posts I have made here you will see the unit installed. I posted up some pics and comments a while back when I did this.
 

jschwartz6

Member
:
USA
:
07 MZ5; 08 CX-9
OK I see your old post. Thanks for the info.
With the Bose amp and such, did you have to run any wiring through the vehicle or manipulate anything in the back? Or was all your work in the center dash (plus a little to the left for the mic)?
 
OK I see your old post. Thanks for the info.
With the Bose amp and such, did you have to run any wiring through the vehicle or manipulate anything in the back? Or was all your work in the center dash (plus a little to the left for the mic)?
All the work was in the dash and placing the mic under the steering wheel. I put the mic there to keep it out of any potential wind, from either the windows or the A/C vents. It works just fine and I am very happy with the results. I added an additional wireless adapter after that install and placed it right up by the drivers knee bolster.
 
:
2009 Mazda CX-9 GT
A local reputable car audio chain store said don't replace the HU unless I do the entire system (speakers & amp too) because replacing a single component will mess up the sound. Believable, but I wanted a second opinion.
Rubbish.

I'd like to verify, have any of you put in an aftermarket head unit to the Bose system, left everything else stock, and all worked out well? I'd be getting a good quality unit such as Kenwood.
If so, any pointers or trouble spots? (I've previously replaced head units in three other vehicles with 4-6 speakers and no amps or subs).
Yes I have.

 

jschwartz6

Member
:
USA
:
07 MZ5; 08 CX-9
Yes I have.

Thanks for the comment. I had seen your post but couldn't tell if you had left all the rest of the system stock which was the key question for me.
 

jschwartz6

Member
:
USA
:
07 MZ5; 08 CX-9
So I bought the parts and did my install the other day. I'm about to leave a negative review for our local reputable chain shop that said it shouldn't be done...

Got a Kenwood head unit and the accompanying supplies (Metra dash adapter and PAC wiring adapter) from Crutchfield. It maintains the use of the factory amp. And I was excited to learn that this PAC unit did not require me to tap into the vehicle wires, which I had to do with my 2007 Mazda5 and 2006 Accord.

I'll write up a few things to make it easier in case anyone is still yet to install an aftermarket head unit in a first gen CX-9.
Keeping in mind that mine is a 2008 with the factory Bose 10-speaker system, no nav, no DVD, no rear camera.

Here's a shot of all the pre-wiring done. Crutchfield's wiring guide (which they email to you with your order confirmation) was extremely helpful.
IMG_7051.JPG


I ended up calling Crutchfield three times though. First time was to ask about the smaller wire harness I found plugged into the factory HU, as shown here. They confirmed that it is to be left unconnected (as there is nothing to connect it to).
IMG_7056.JPG


Second call made me feel silly; I was getting no sound but I hadn't plugged the RCA speaker wires from the PAC harness to the back of the head unit. Given that the head unit speaker wires were to be left unconnected, I'd been confused. Got the RCA jacks plugged into the HU and all was well until I tested the fade and balance. All speakers were working but they were all basically on the front channels, so fading all the way to the back just muted all of them. Third phone call to Crutchfield... Turns out, the vehicle maintains a digital fader which you can access by holding down the Mode button on the steering wheel. So leave the HU fader on center or front. You can also customize the text readout on the factory upper LCD display.

I decided to take the easy route with the microphone and routed it to the top of the steering wheel. Didn't even have to pull another panel to get it there.

My head unit has a rear USB connection (in addition to a front) and I decided to cut away a small corner of the vehicle's lower pocket where the rubber pad meets the plastic wall, so that the USB cord could come through. Sorry no photo. It was really nice that the pocket has those two separate pieces which come apart so I didn't have to cut a hole big enough to fit the entire USB plug. The cutaway is practically invisible in the back corner.

One bad thing I discovered post-install: The auto-down and up function for the front windows doesn't work anymore. Holding down the switch still works so we can live with it.
 
:
2009 Mazda CX-9 GT
One bad thing I discovered post-install: The auto-down and up function for the front windows doesn't work anymore. Holding down the switch still works so we can live with it.
Because you had the battery disconnected and reset the windows. Just need to re-program them.
 

jschwartz6

Member
:
USA
:
07 MZ5; 08 CX-9
Because you had the battery disconnected and reset the windows. Just need to re-program them.
Oh OK, that's good, how do I do that? Do I have to go to the dealer?
What was their reason?
Basically they said the Bose system is all tuned for every component to work together and so replacing one component would disrupt the balance and cause it not to function properly if at all. Again this was believable but I think the key here, if I understand it right, is that the aftermarket HU is basically just connecting to the factory amp which oversees all the sound output so the proper signals are maintained.
 
:
South Carolina
:
12 MZ5 13 CX-5
To reset the window, roll the window up, but continue to hold the switch for a couple more seconds. Now roll it down, and do the same.

After that, should be reset.
 
:
2010 CX-9 GT
To reset the window, roll the window up, but continue to hold the switch for a couple more seconds. Now roll it down, and do the same.

After that, should be reset.

You have to do it the other way: hold the down button until it's all the way down, then hold the button until it's all the way up and continue to hold the button up for 3 seconds. The car will beep.
 
:
2009 Mazda CX-9 GT
Basically they said the Bose system is all tuned for every component to work together and so replacing one component would disrupt the balance and cause it not to function properly if at all.
Well, as long as they stick to their story. 😂

Just a new deck and my system sounds so much better.