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Mazda3
01-04-2008, 05:17 PM
At the request of a CX-9 member I am posting some info on the AWD and TCS on the CX-9. I posted this info in the CX-7 forum about a year ago, but some CX-9 members will find it useful.


Here is the explanation right out of the Mazda training manual:

"The CX-7 is equipped with Mazda’s new active torque split all-wheel drive system, which
debuted on the MazdaSpeed6, featuring a more aggressive transfer of torque to the rear
axle in accordance with driving conditions. This intelligent system achieves a satisfying
balance between the interactive control over the vehicle that makes it particularly enjoyable
to drive, and confident handling stability necessary for snowy, wet or other uncertain road

surfaces/conditions; engine power and torque are faithfully and efficiently transferred to the
road surface for maximum performance.
The active torque split AWD system uses real-time data input on steering angle, yaw rate,
lateral G-force and engine status to determine road surface and driving conditions. The CX7’
s onboard computer then automatically determines which of three different modes of
front/rear torque distribution should be engaged: Normal, Sport, or Snow (for slippery
surfaces). The active torque coupling mounted in front of the rear differential is
electronically controlled in accordance with the data provided by the computer, adjusting
front/rear wheel torque distribution between 100:0 and 50:50 to deliver optimum drive
power to each axle. The result is that the most power and traction are made available under
all conditions; positive acceleration and confident handling are provided regardless of
constantly changing road conditions, as well as the ability to fully balance the vehicle in a
turn by skilful use of the accelerator pedal.
Unlike many competitor offerings, the torque transfer system in the CX-7 seamlessly
integrates the inherent stability of all-wheel drive; because the active torque coupling is
controlled electronically, it can react to wheel slippage much more rapidly than conventional
gear- or fluid-controlled systems. To ensure consistent power delivery under all weather and
driving conditions, the Power Take-Off (PTO) system on the centre differential that
distributes torque to the rear axle is fitted with its own liquid-cooled cooling system. "

Once the computer has shifted into snow or sport mode it pre-loads the rear axle so you don't have to wait for slippage. As oppossed to the system in the 01-04 Tribute where the wheels had to actually slip before the AWD kicked in.



For those debating the TCS system here is the blurb from the manual on that:

"The braking system works in synergy with the CX-7’s Dynamic Stability Control (DSC),
incorporating a traction control system (TCS), to exhibit an outstanding level of active
safety. The Dynamic Stability Control system is designed to activate when the vehicle is
taking a turn too quickly for the road conditions. DSC compares the driver's intended
direction (from the steering wheel angle) to the actual vehicle path; if the system senses
understeer or oversteer, it applies braking force, and reduces engine torque if required, to
correct the situation.
Traction control systems generally come in one of two primary systems: an ABS-based
system, or an engine management system. Both systems use the ABS wheel speed sensors
to determine if there is wheel spin (wheel speed greater than vehicle speed). The CX-7
system uses engine management to reduce the amount of power output by reducing fuel,
ignition timing and throttle position to reduce wheel spin. This system is superior to systems
that use the ABS brakes to slow down the spinning wheel – ABS systems have a tendency
to be very jarring in their operation and can overheat the brakes if used for extended
periods of time. The CX-7’s traction control system (TCS) deals with the problem of the
engine supplying too much power for road conditions right at the source; when wheel spin is
detected, the TCS simply reduces the engine’s power output until the wheel spin stops.


Please feel free to ask questions, I'll help as best I can.

not_too_shabby
10-27-2008, 07:24 PM
How do you shift into snow or sport modes in a CX-9?

"Once the computer has shifted into snow or sport mode it pre-loads the rear axle so you don't have to wait for slippage. As oppossed to the system in the 01-04 Tribute where the wheels had to actually slip before the AWD kicked in."

ceric
10-29-2008, 01:02 PM
You don't.
The compute makes the decision to shift into which mode for you.
Someone on other board claims that our CX9s are not equipped with the PTO (Power Take-off) system. Can you confirm this? I can't be sure either way from reading the WorkShop manual.

Mazda3
10-29-2008, 04:00 PM
The CX-9 has the same set-up with the sport mode or PTO as they call it.

not_too_shabby
10-29-2008, 04:40 PM
Is there any way to force it into sport mode?

Mazda3
11-03-2008, 04:02 PM
Is there any way to force it into sport mode?

Sport mode is triggered when you get hard on the gas.

not_too_shabby
11-03-2008, 05:37 PM
Thanks, I'll have to to try that after I get over 1000 miles...

jbunderson
12-07-2008, 11:33 PM
Has anybody else heard of this? I was up in the mountains and my AWD quit. I ended up sliding to the side of the snow covered road, and only the left front tire would spin. Then the TCS light would flash and that tire would stop. When I would turn the TCS off, I could hear multiple clicks coming from that wheel.
We got pulled out after hiking to the top of a mountain to get cell phone service.
Took it to the dealer on Tuesday morning. As of Friday, they called and said they think it is electronic, but have a call in to tech support (LOL). They said that once they figure out the electronics, then they can check the mechanical.
2007 CX-9 Touring AWD 30,000 miles.

not_too_shabby
12-08-2008, 11:59 AM
Has anybody else heard of this? I was up in the mountains and my AWD quit. I ended up sliding to the side of the snow covered road, and only the left front tire would spin. Then the TCS light would flash and that tire would stop. When I would turn the TCS off, I could hear multiple clicks coming from that wheel.
We got pulled out after hiking to the top of a mountain to get cell phone service.
Took it to the dealer on Tuesday morning. As of Friday, they called and said they think it is electronic, but have a call in to tech support (LOL). They said that once they figure out the electronics, then they can check the mechanical.
2007 CX-9 Touring AWD 30,000 miles.

Wow, that's not good. Keep us posted. How did it work before it quit? I haven't taken mine up in the snow yet.

jbunderson
12-08-2008, 05:27 PM
The dealer called today and said that the AWD module and the rear solenoid had gone out and needed to be replaced. They expect to have it back to me tomorrow afternoon. Dropped it off a week ago Tuesday morning, and get it back a week later on Tuesday afternoon. They said that when the AWD module went out, I was basically the same as FWD. It was a drastic difference, especially on gravel roads or snow and ice. I definitely would recommend the AWD over FWD.
I hope that the fact that it took so long to diagnose means that this is somewhat unique and not that the dealer is not knowledgeable.

Neuritis
12-10-2008, 08:21 PM
I've been driving my AWD GT on some pretty slippery snow and ice covered roads, but the car has never switched to AWD (or at least I can't tell). I only see the brief flash of 4WD light in the speedometer when I start the car, but never when it is running. Is that normal? I've been pretty aggressive as well with the car sliding, so not sure why it doesn't kick into AWD.

jbunderson
12-10-2008, 09:21 PM
I got the CX-9 back from the dealer today, Wednesday, after they had it since last Tuesday, and they told me it was just a faulty AWD module. However, I decided to try it a bit on a section of dirt. The TCS light flashed and the AWD flashed and stayed flashing for about a minute. In other words, I think there is more problems that they didn't fix. Before this, the AWD never came on, even on ice and snow.

squidly
12-11-2008, 10:17 AM
When the AWD light apperead on a few other CX-9's here, it was a bad transfer case or something like that. The Ford Edge has the same one with the same problems.

Neuritis
12-11-2008, 10:43 AM
So if I'm interpreting the last two messages correctly, the car will go in and out of AWD without me knowing? There's no indication that it is in the AWD mode and the light is really indicating a problem with the AWD system?

Mazda3
12-11-2008, 10:52 AM
So if I'm interpreting the last two messages correctly, the car will go in and out of AWD without me knowing? There's no indication that it is in the AWD mode and the light is really indicating a problem with the AWD system?

That is correct. The AWD system is seamless. You should never know there isn't power to rear tires all the time. The 4wd light is a problem light. The only light you should see flashing is the car with the tire marks when the DSC kicks in.

nhokt
12-21-2008, 09:49 AM
Like some of the others said it doesn't feel like we are getting AWD in the snow. We just got some nice snow in MA on Friday (8-12" with more today) I took a ride to the grocery store with a hidden motive of testing the AWD system. I our long drieway I goosed it and basicaly slid around typical of my front wheel drive cars. Pulling out of the snowy grocery parking lot onto the main road was the same, lots of front tire spinning with the TCS light on, never felt any help from the AWD system. Any suggestions?

Force-1
12-21-2008, 10:47 AM
Like some of the others said it doesn't feel like we are getting AWD in the snow. We just got some nice snow in MA on Friday (8-12" with more today) I took a ride to the grocery store with a hidden motive of testing the AWD system. I our long drieway I goosed it and basicaly slid around typical of my front wheel drive cars. Pulling out of the snowy grocery parking lot onto the main road was the same, lots of front tire spinning with the TCS light on, never felt any help from the AWD system. Any suggestions?

I did the same thing last week. When I went to work Tuesday morning my street was snow/ice covered (rare here in Albuquerque). I decided to take the opportunity to test the AWD. Each time I floored it, it accelerated nicely, straight as an arrow, no flashing lights of any kind on instrument panel. I laid on the brakes several times too, causing the anti-lock to kick in each time, so I know the roads were slick.

In my case, AWD seemed to work as intended.

squidly
12-21-2008, 03:03 PM
I have to say that I am super impressed with how much the control systems allow when you are trying to have fun. If I give it enough gas around a corner, it will drift just perfectly... the TCS and stability control don't kick in for quite a while. But if I accelerate slower and start to slide/spin, it all kicks in pretty quick. Man, I love when it snows a bunch.

not_too_shabby
12-21-2008, 05:50 PM
Like some of the others said it doesn't feel like we are getting AWD in the snow. We just got some nice snow in MA on Friday (8-12" with more today) I took a ride to the grocery store with a hidden motive of testing the AWD system. I our long drieway I goosed it and basicaly slid around typical of my front wheel drive cars. Pulling out of the snowy grocery parking lot onto the main road was the same, lots of front tire spinning with the TCS light on, never felt any help from the AWD system. Any suggestions?

hmmm...you got my curious to give my AWD system a try. There is a lot of snow on the ground here in Portland. Seems like these seemless systems can be seemlessly not working and there isn't a good way to know for sure until you get into bad conditions and even then you don't really know one way or the other.

nhokt
12-21-2008, 09:57 PM
hmmm...you got my curious to give my AWD system a try. There is a lot of snow on the ground here in Portland. Seems like these seemless systems can be seemlessly not working and there isn't a good way to know for sure until you get into bad conditions and even then you don't really know one way or the other.

I convinced my wife to stand outside and watch to see if the rear wheels were spinning or just the fronts (fresh 8" of snow). Turns out the rear were also spining, so looks like the AWD system works, just the tires suck :-) The snow today is deep and wet makng it super slippy, I had to put chains on the snowblower to clear the driveway, that was a first.

taipham
12-21-2008, 10:06 PM
I rented a Cx-9 AWD for my ski trip. The car could not even go up a slight incline. I can see tire marks from the front wheels, whereas the rear wheels weren't even spinning.
How can I tell whether the car has the AWD option ?
Any exterior or interior visual clues ?
Thanks.

squidly
12-21-2008, 10:28 PM
There's no way to tell whether it has AWD or not, unless you look underneath
for the driveshaft and rear dif. Are you sure you rented an AWD? Most rental places won't carry vehicles with that option.

taipham
12-21-2008, 10:38 PM
There's no way to tell whether it has AWD or not, unless you look underneath
for the driveshaft and rear dif. Are you sure you rented an AWD? Most rental places won't carry vehicles with that option.

Good idea. I'll look underneath before I call Hertz and complain.
I requested for 4WD and at least that's what it shows on the rental agreement.

kosh2258
12-26-2008, 09:55 AM
hmmm...you got my curious to give my AWD system a try. There is a lot of snow on the ground here in Portland. Seems like these seemless systems can be seemlessly not working and there isn't a good way to know for sure until you get into bad conditions and even then you don't really know one way or the other.

Not correct. There is a way to tell if the AWD system is not functioning. There is an indicator light on the instrument panel that will flash if there's a problem. It's the yellow 4WD light. If that indicator is on or flashing, there's a problem being detected with the system.

I know this from personal experience when the transfer case on my 9 failed. That light was flashing when I was driving on snow and ice but getting no power to the rear wheels - the system sensed the difference in wheel speed between front and rear. Since I had the transfer case replaced, and the AWD is now working, I haven't seen that indicator light again.

Ted

not_too_shabby
12-26-2008, 11:25 AM
Not correct. There is a way to tell if the AWD system is not functioning. There is an indicator light on the instrument panel that will flash if there's a problem. It's the yellow 4WD light. If that indicator is on or flashing, there's a problem being detected with the system.

I know this from personal experience when the transfer case on my 9 failed. That light was flashing when I was driving on snow and ice but getting no power to the rear wheels - the system sensed the difference in wheel speed between front and rear. Since I had the transfer case replaced, and the AWD is now working, I haven't seen that indicator light again.

Ted

No, I am correct. You can't tell the 4WD system is not working until you are in conditions that you need it. From what you just posted you didn't know your system was not working till you drove on snow and ice. I would rather not be on snow and ice then find out my system is not working

I did take it out yesterday in fairly deep snow and some ice and it did pretty well. The roads are so rutted that you can't help but stay on track . I did take it into a slushy parking lot and made some hard turns but there was no spinning or drama. Overall it did better than I thought considering I have the 20" stock tires.

kosh2258
12-27-2008, 12:10 PM
No, I am correct. You can't tell the 4WD system is not working until you are in conditions that you need it. From what you just posted you didn't know your system was not working till you drove on snow and ice. I would rather not be on snow and ice then find out my system is not working

I did take it out yesterday in fairly deep snow and some ice and it did pretty well. The roads are so rutted that you can't help but stay on track . I did take it into a slushy parking lot and made some hard turns but there was no spinning or drama. Overall it did better than I thought considering I have the 20" stock tires.

Uh, you didn't qualify your statement in that way the first time. You said:
"...there isn't a good way to know for sure until you get into bad conditions and even then you don't really know one way or the other."

You're correct in that the problem doesn't clearly show itself until the vehicle gets into poor traction conditions but there IS a definite way to tell if the system is malfunctioning. You can tell definitely one way or the other. So no, you weren't completely correct in your first statement. My only objective was to point out to people that there is a way to know - even if it is at a bad time for finding out.

I do agree with your point that it would be better to know there's a problem before the system was needed and would like a way of testing the system in good road conditions.

Ted

tony89
01-21-2009, 04:47 PM
So are the TCS and AWD systems completely independent?

Does the TCS light indicate AWD operation?

Mazda3
01-22-2009, 12:23 PM
Does the TCS light indicate AWD operation?

No.

Boldlygo
07-09-2009, 10:25 PM
Just keep in mind everyone that when it snows, snow tires are called for! The factory tires are NOT snow tires, they are 3 season tires. If you live where it snows, 4WD or not, you should have snow tires on. Hey, it's the law in Quebec now!

CX9inMA
01-05-2010, 04:38 AM
Not correct. There is a way to tell if the AWD system is not functioning. There is an indicator light on the instrument panel that will flash if there's a problem. It's the yellow 4WD light. If that indicator is on or flashing, there's a problem being detected with the system.

I know this from personal experience when the transfer case on my 9 failed. That light was flashing when I was driving on snow and ice but getting no power to the rear wheels - the system sensed the difference in wheel speed between front and rear. Since I had the transfer case replaced, and the AWD is now working, I haven't seen that indicator light again.

Ted
I have this exact problem. Can you (or anyone) tell me approximately how much it will cost to have the transfer case fixed?

I am unfortunately out of warranty. :(

shoorne09
01-27-2010, 05:20 AM
Err I cant seem to find my "brain" or "shock sensor" or ANYTHING mainly cus I have no clue how it all works. How would I actually get to it? Or usualy? Thanks

Al's Chop Shop
02-04-2010, 09:17 PM
might be worth noting....

in the FWD, i have noticed the TCS system will only apply the ABS when one tire spins, but it will actually pull engine power when both wheels slip at the same time. it makes sense, though a block away from my house is a very steep hill with a stop sign. both tires always slip in the rain on the painted white line, and the TCS then kills engine power. at almost full throttle, the engine has so little power it can hardly pull me up the hill, but the wheels have stopped spinning as soon as they were off the white line. it takes probably 5 or 6 seconds for the engine power to return to normal.

not a bad thing, but interesting, at least in my book.

Al

blink_me192
02-04-2010, 09:44 PM
take a look at this video on the operaiton of the 6 MPS (Mazdaspeed6) All-wheel-drive system. From the looks of things, there is always SOME torque going to the rear wheels unless at low speeds or cruising. But the moment there is any accerleration torque is sent rearwards. Quite interesting.

heres the link

http://www.youtube.com/watch?v=uOWGq1B8C84

dmitrik4
05-20-2010, 10:20 PM
i can tell you that both the CX-7 and CX-9 AWD systems work brilliantly in the snow. our CX-7 lease ended in December, and we replaced it with an AWD CX-9. we got socked here in Philly this past winter, and even on old all-seasons, our CX-7 plowed through 12" inches of fresh snow with no problems. i was really surprised. also, when turing from a stop, you can certainly feel the torque sent to the rear as the rear will kick out under aggressive throttle application.

we got heavy snow before and after new year's, and the 9 got through ~15" with no trouble. i think the 9's limited slip diffs also really help. the 7 was much more lively while plowing through deep snow, while the 9 just kind of marched straight ahead with no drama.

blink_me192
06-02-2010, 10:05 PM
Hey guys,
This is an interesting vid i found on the Australian Mazda website.

Did you know that the CX9 has an LSD? :-P I didn't.

http://www.mazda.com.au/Design-and-Technology/Active-Torque-Split.aspx

And from the vid, seeing as it was demonstrating the AWD system in the body of a 2nd Gen 6, i think Mazda HQ has a 2nd Gen MPS6 as a concept, but is only waiting for the green light from the US. Please oh please let there be another MPS6.

mihalis
01-21-2011, 11:07 AM
Hey guys,
This is an interesting vid i found on the Australian Mazda website.

Did you know that the CX9 has an LSD? :-P I didn't.

http://www.mazda.com.au/Design-and-Technology/Active-Torque-Split.aspx

And from the vid, seeing as it was demonstrating the AWD system in the body of a 2nd Gen 6, i think Mazda HQ has a 2nd Gen MPS6 as a concept, but is only waiting for the green light from the US. Please oh please let there be another MPS6.

No I didn't. All I know is that with the AWD and snow tires, the cars handles snow very well. I drove it today as my wife decided to work from home. All the back roads had not been plowed, yet it still handled around the bends without any issues.

ceric
01-21-2011, 12:44 PM
Great video.
However, your link is wrong.
Here is the correct one.
http://www.mazda.com.au/Design-and-Technology/Active-Torque-Split-All-Wheel-Drive.aspx

I knew there is a differential, but didn't know that it is limited-slip.

Antonio DiMarco
01-21-2011, 12:58 PM
This morning, as I was negotiating our CX-9 through yet another snowfall in the NE I wondered if the system actually behaves differently whether the tranny is in auto or manumatic mode. My guess is that it does, though I can't be sure. Since the computer can no longer depend on the transmission being in a particular gear at a particular time. So when the tranny is in manumatic mode there is probably the possibility that the system can't react or make well-informed decisions fast enough. Of course the system probably reacts pretty quickly so any lag or user-input as far a manual gear change probably isn't enough to confuse it. Anyone have any insight here? It may have been my imagination but I thought the car behaved better with the tranny in auto mode. I felt like the CX-9 had more of tendancy to throw out it's tail when I was manually shifting.

sjg
01-31-2011, 11:02 AM
I felt like the CX-9 had more of tendancy to throw out it's tail when I was manually shifting.

Could be. You might be holding a gear longer than the auto would and letting the engine rev to greater torque and power. This could allow your tires to lose grip. I've used the manual in snow to start in 2nd gear and then try to upshift as soon as possible...the opposite of what I usually would use manual mode for.

Antonio DiMarco
01-31-2011, 12:30 PM
Yeah I use manual mode to start in 2nd gear as well, especially in my Mz6 so I can crawl over any ice. Once I crawl out I set it to auto. Over the last couple weeks I've started forgetting about manually shifting during the winter and letting the computers handle it. Will go back to having fun once thw wweather stops dumping tons of snow on our heads. Man and it's only January!