Help! 2007 CX-7/CX-9 BOSE amp and speaker question.

Hi all! I came across this forum trying to research solutions for my Japanese 2007 MPV (also called Mazda 8.) After countless hours of trying to find a solution by myself, I thought Id try to crowdsource an answer. My MPV came with a factory BOSE amp and an 8 speaker system. For its time it was an amazing system (factory touchscreen navigation with front, side and rear cameras, Bluetooth phone connection, and steering wheel controls.) I had the head unit set up with a RC headphone connector for my old iPhone 6s and the navigation was working ok. But recently the screen has lost its sensitivity, and more importantly, I updated to an iPhone XS which has no earphone jack. I tried to buy an iPhone adaptor, but it creates a buzzing noise, especially if I connect it to the lightening cable for power. So, I thought this would be a good time to upgrade the head unit. Thats when my nightmare began as I found out how hard it is to upgrade this particular setup. I did however, find out that the BOSE amp appears to be the same as used in CX-9 AND CX-7s so Im hoping someone on this board can help.

I want to continue to use my BOSE amp and 8 speakers with a new head unit. Is this possible? Some say it is, and others say it isnt. If it is possible, what is the exact Mazda Bose interface that will work, and what wiring would need to be done to connect it to the new H.U.?

Regarding the three cameras, and steering remote, I think I have that covered. Its now just down to the intergration with the BOSE amp and speakers.

Any advice would be greatly appreciated!
2019 CX-9 GT AWD in Soul Red
If you want to keep the old headunit with your iPhone XS using an adapter, you need to find an adapter with a Ground Loop Noise Isolator. This will remove the buzzing sound when you have it plugged in for power. Something like THIS.

I use THIS one on my Mazdaspeed3 since the OEM headunit does not have BT function.

Otherwise, it's very easy to keep the OEM speakers; you just need to make sure that the headunit speaker outputs are wired to the respective speakers. For the amp and sub, it might be a little bit harder but if it's anything like a conventional amp and sub set up, then you just have to provide the amp the signal from the headunit and it should be okay, hopefully. My suggestion though is to ditch the OEM amp and sub and go aftermarket as they are much better.

Have you looked at headunits that retain all functionality? Sometimes you just need a harness adapter to connect everything up and it retains all functionality. Try contacting and see if they can help. They are based in the US but from my limited reading, the CX-8 is just a shorter version of the CX-9 so they might be able to cross-reference parts for you.

Good luck!
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Thanks SO much Azusu! I will probably end up using your advice on the Ground Loop Noise Isolator if in the end I cant do what I want. But what I really want to know is what exact part will allow me to connect my factory BOSE amp AND speakers to an aftermarket head unit. I know BOSE is tricky and I dont want to buy an expensive H.U. and have it not work.

Again, thanks for your advice!
Hi again. I thought I had found a solution to my BOSE amp connection issue talking to a local automotive parts store here, but suddenly got a call from them in which he said that the part they had recommended wouldn*t work as the harness from the factory headunit is a 20-pin and the adapter is 24-pin, so it won*t work.

So, I want to confirm, what is the connector on the 2007 CX-9 and CX-7 BOSE stereo headunit? Is it a 20-pin connector as well. And if so, is there a work-around to connecting it to the BOSE amp?

Thanks in advance!