2011 CX-9 OEM Radio must remain in vehicle for A/C to work!

NCMazda6

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2014 Liquid Silver Mazda6
That's right, it sounds rediculous but it's true. My wife has a 2011 Grand Touring, no nav. I installed her Pioneer AVIC-X910 that I pulled from her CX-7 and everything was great. We took a trip to GA the next day and notice the A/C wasn't working...the compressor was not kicking on. So we carried it to the dealer yesterday for it's first oil change, tire rotation, and to get it fixed and after having it all day and talking to Mazda, the techs came up with this printout for me.

Applicable Model(s) VINS
2011 CX-9

Description
"Some vehicles my exhibit no cold air from the front/rear vents after the installation of an aftermarket audio unit. Improper operation of the original audio system may also cause this concern."

Repair Procedure
"The audio unit provides information to other modules on the MS-CAN that is used to determine if the A/C compressor request should be sent to the PCM. The original audio unit must remain connected and functional in order for the A/C compressor to operate correctly"

Yeah, sounds like bologne to me. BUT, I took my wife's car home and plugged her OEM radio into the T-Harness that I installed to be able to change her clock and sure enough, the A/C came right on. Soooo, I extended the T-harness to the trunk and placed her OEM radio under the rear floor. I didn't bolt it down yet...I still have to install her JL Audio 5 ch amp back there and don't want to go making too many holes. But her A/C works and she gets to keep her gas mileage info since it goes away with the radio.

So, since I don't know if all CX-9s are like this, if you change the radio out, check your A/C after you unplug your OEM unit. Metra makes the T-Harness...I don't remember the model number but it's on their website. If your A/C still works, then just put the T-harness end in the glove box so you can change your clock.
 
It's not unheard of. Lots of cars have the HVAC system integrated into the factory stereo unit. My 2005 Subaru Legacy GT was like that. I couldn't switch out the factory radio for anything else unless I wanted to completely lose my HVAC system.
 
Well, it appears that Mazda has realized their mistake and is now sending a module to correct this issue to my dealer for our CX-9. The dealer called the other day and said that they had released it within the hour when Mazda called him to say they were sending one to them. So we'll see how this works.
 
Thanks for the info!
I would assume a technical bulletin was released to all the dealers. This would save a lot of time for other trouble shooting this.
 
That's right, it sounds rediculous but it's true. My wife has a 2011 Grand Touring, no nav. I installed her Pioneer AVIC-X910 that I pulled from her CX-7 and everything was great. We took a trip to GA the next day and notice the A/C wasn't working...the compressor was not kicking on. So we carried it to the dealer yesterday for it's first oil change, tire rotation, and to get it fixed and after having it all day and talking to Mazda, the techs came up with this printout for me.

Applicable Model(s) VINS
2011 CX-9

Description
"Some vehicles my exhibit no cold air from the front/rear vents after the installation of an aftermarket audio unit. Improper operation of the original audio system may also cause this concern."

Repair Procedure
"The audio unit provides information to other modules on the MS-CAN that is used to determine if the A/C compressor request should be sent to the PCM. The original audio unit must remain connected and functional in order for the A/C compressor to operate correctly"

Yeah, sounds like bologne to me. BUT, I took my wife's car home and plugged her OEM radio into the T-Harness that I installed to be able to change her clock and sure enough, the A/C came right on. Soooo, I extended the T-harness to the trunk and placed her OEM radio under the rear floor. I didn't bolt it down yet...I still have to install her JL Audio 5 ch amp back there and don't want to go making too many holes. But her A/C works and she gets to keep her gas mileage info since it goes away with the radio.

So, since I don't know if all CX-9s are like this, if you change the radio out, check your A/C after you unplug your OEM unit. Metra makes the T-Harness...I don't remember the model number but it's on their website. If your A/C still works, then just put the T-harness end in the glove box so you can change your clock.

Could you give the parts needed to install an aftermarket radio in a 2011 CX-9?
 
I'm hoping the 2012 is the same as the 2011.

I ordered the Scosche dash kit, the metra t-harness to allow the bose amplifier and speakers to continue to be used through the RCA output from my head unit, and the universal steering will control unit to install my Kenwood dnx7160 in mine.

I'm hoping it will all work.

I will try to post pics and more info with the results in a couple weeks when I can get time to do the install.

Again, this hasn't been confirmed to work yet, but here's what I ordered:

AMAZON: Axxess Interface MZTO-01 Mazda Turn On 2007-2008 Mazda CX-7 and CX-9 with Bose Sold by: Depot Repair Services, LLC. $59.52
(says 2007-2008 on one site and then on Metra site it is listed for up to 2010. Was used here by NCMazda6 on his 2011, so I'm taking a leap of faith that it will work on the 2012)

AMAZON: Metra Axxess ASWC Universal Steering Wheel Control Interface (Black) Sold by: audioonline $47.00
(hoping this will actually work with my phone hook and unhook controls as well as my Kenwood has bluetooth from Parrot built in. I'm doubting this will work though so probably just volume and that's about it)

Scosche.com: MA1545B 2007-UP MAZDA CX-9 DOUBLE DIN AND DIN WITH POCKET $34.95
(bought the scosche kit because in past experience, scosche kits just seem to be better built than metra. I suppose either woudl work fine though - hoping so anyway)


Will post in my other thread the results of this install.
 
@ PMmightymavkev: Cool look forward to your install!
@NCMazda6 : Could you let us know the P/N of this module when you receive it from the dealer? I called some dealers around me and no one has nay idea!
 
Took the dash apart on the 2012 today. I'm still waiting for the parts to come but wanted to tear into it a little bit to make sure everything looked OK before I run out of "holiday week" and have to go back to work.

I noticed that the Antenna is not standard either. Not sure why that isn't mentioned anywhere, but you'll definitely need an adaptor for any aftermarket head unit. Metra's web page acknolwedged it but while it comes up for the Mazda as a fit, it's listed as a Honda adaptor. I ordered it anyway from Amazon because it looked correct from the pic and it was only $8.99.

here's the link:

http://www.metraonline.com/part/40-HD10

I'm going to assemble all of this in my thread also and start posting there as I go.
 
I have not personally tried it, but according to a post in Which is the best 2 DIN stereo player for 2010 Mazda CX-9, the connects2 CTSMZ011 Stalk Adapter:

  • solves the A/C issue that stops the A/C from working on 2011 models when you replace the stereo.
  • also allows to use the steering wheel buttons to control the clock and the car computer.
Here is the installation guide.
I'm going to give that adapter a try...I just ordered one and will return the Axxess unit.
I assume the radio itself will function fine without any of these modules. It's going to take over a week to get the Stalk Adapter and I'm looking to install the radio this weekend.
 
Z-Thrizzle:

ARe you going to install first with the AXXESS adapter and then swap it out for for the Stalk to compare? I'd be interested in the results of each is why I'm asking becuase I may do the same thing if you find the Stalk is better.
 
Happens on the 2012 with Bose as well. I just hooked mine up with the Axxess T- Harness (MZTO-01) and the A/C doesn't work unless the OEM head unit is plugged in to the harness as well. Crap. I was hoping they fixed that.

Oh well.
 
I'm planning to return the Axxess unit so I haven't installed it. I finished the installed and my A/C also doesn't work. I'll keep you posted on how the Stalk adapter works after I get it in a week or so.
 
Hey Z-Thrizzle, just to clarify, are you getting the Stalk adapter that is just for the steering wheel controls or the radio hook up interface as well (or is the one adapter for both)? Their information is very sketchy and that installation guide is kind of a joke.

I'm almost ready to call them over there and talk to them directly about whether this things really works or not. We have one post who says it does so I'm hoping they're right and there's not something different about the models in the US vs. elsewhere.

I'm going to do the T-Harness extension trick tomorrow and connect the OEM head unit in the back under the trunk box. Shouldn't take long. I left a "fish" wire under the carpet to pull my Sirius SAT Antenna lead extension wire through later when it comes so I should be able to pull the wires to extend that T-Harness through with that. If I'm right, it won't take more than 30 minutes I don't think (I know, famous last words probably).
 
yeah the description is vague. I think the harness comes with the radio hook up along with steering wheel connections. For a 100 bucks it better include everything!

*Edit*
Looks like I'll be getting the harness the end of next week. I'm going on a roadtrip that Sat but if I get it that Fri I'll install it that night and see how it works.
 
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Well, I fixed my A/C by buying some wire and cutting the T-harness off behind the glove box where I put it. I then spliced the new wires into the cut ends and ran them back to the cargo area under the trunk box. I then spliced the harness connector into the wires I ran back there and plugged it into the OEM head unit.

Will just have to leave the OEM head unit plugged in. The A/C works though.

However, I noticed the BOSE amp clips the sound off now when turning it up loud. Last night before I did this the stereo would go really loud without any such clipping. So I'm afraid that while I may have fixed my A/C, it may be affecting the BOSE amp signal somehow connecting that T-harness up to the OEM head unit.

I really hope that other harness works for both the a/c problem as well as the steering wheel and clock controls.
 
UPDATE on my sound cutting in and out problem.

I played around with the T-Harness a bit tonight to see if I could figure out which wire might allow the amp to work right if I disconnect it and maybe still let the A/C work and I stumbled onto a discovery.

In all of my previous tests, the sound cut in and out so bad I was afraid I was hurting something electrically so I disconnected the OEM Head Unit from the T-Harness right away.

Tonight, I wanted to check for a short or bad connection in my "extension" that I did so I let the stereo play while messed with the connections back in the cargo area.

Low and behold after about 30 seconds, the cutting in and out stopped and the sound started working fine. I took a drive to test it and it never cut out again and the A/C is working.

It seems that when the OEM unit is first plugged in, there is some kind of "boot up" process that it must be going through or a "self test" or something that is causing interruption in the signals on those wires that interfere with the Aftermarket Head Unit signal going through the harness at the same time. After a few seconds, it settles down and it appears that it doesn't need to do it anymore as long as it stays plugged in.

Becuase I was unplugging mine each time I thought it was messed up, it had to do this "self test/boot up" thing each time I tried again and I wasn't giving it enough time to get finished.

This is good news because now all I need to do is figure out how to get the steering wheel controls to work with my Kenwood deck and we should be in good shape.

Z-Thrizzle - I'm still anxiously waiting to see the results of the install of your Connects2 harness from the UK. If that thing allows working with the clock and computer through steering wheel controls and still allows the A/C to work, I'd much rather have that then my OEM head unit plugged in forever in the back of the car.
 
I finally got some tracking info. (I emailed the seller asking for it) It was sent to the US by Royal Mail.
ROYAL MAILYour item, posted on 25/11/11 with reference RF439226712GB has been passed to the overseas postal service for delivery in UNITED STATES OF AMERICA.

It sucks that it doesn't say when it got to the states or gives you the tracking of the shipping company it was handed too. Well since it's in the states now there's a chance I may get it by this weekend. *Fingers crossed*
 
UPDATE on my sound cutting in and out problem.

Low and behold after about 30 seconds, the cutting in and out stopped and the sound started working fine. I took a drive to test it and it never cut out again and the A/C is working.

It seems that when the OEM unit is first plugged in, there is some kind of "boot up" process that it must be going through or a "self test" or something that is causing interruption in the signals on those wires that interfere with the Aftermarket Head Unit signal going through the harness at the same time. After a few seconds, it settles down and it appears that it doesn't need to do it anymore as long as it stays plugged in.

Becuase I was unplugging mine each time I thought it was messed up, it had to do this "self test/boot up" thing each time I tried again and I wasn't giving it enough time to get finished.

This is good news because now all I need to do is figure out how to get the steering wheel controls to work with my Kenwood deck and we should be in good shape.


I spoke too soon. Problem was back tonight. There's either a bad connection in my wire "extension" or at the back of the OEM head unit or there's something in the circuitry of the OEM head unit that is sending a interference back through to the plug that is sending signals to the BOSE amplifier or something.

I really need to find a solution here!!! I'm so close to having this work GREAT and yet having no A/C is not an acceptable trade off.

I hope the Connects2 harness works because I'll be ordering one immediately.
 
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