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hey im new to this forum and the other day i found a link for a how to for turning off my awd to make it just fwd, but now i cant find it, can someone help me?
 

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QUOTE (06speed6* @ Jan 13 2010, 01:05 AM) index.php?act=findpost&pid=1629379
hey im new to this forum and the other day i found a link for a how to for turning off my awd to make it just fwd, but now i cant find it, can someone help me?[/b]
pull ebrake up one click.

Unless you are wanting to disable it by disconnecting key parts, then thats a different animal.
 

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There is. Brown wire to the AWD box gets cut and spliced into a switch to ground. Search under Forzda. He might have written it. I can't remember what thread it was.
 

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Hello guys, this is my first reply or even post... I was always curious about this AWD vs handbrake condition, so I intentionally parked the with the front wheel on ice and then attempted to spin the front wheels with the parking brake pulled, well guess what, the wheels would not "really" spin at all and I could "feel" the engine was trying to spin the rear wheels !!! On the other hand, I do get this infamous pulsing vibration on smooth roads at 100 to 120 KMH and it does disapear when I then pull the parking brake up til the light comes on. Can anyone explain ??
 

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QUOTE (jmhinkle @ Jan 13 2010, 06:05 AM) index.php?act=findpost&pid=1629390
There is. Brown wire to the AWD box gets cut and spliced into a switch to ground. Search under Forzda. He might have written it. I can't remember what thread it was.[/b]
Yep, here it is in a pdf file.
 

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QUOTE (louis1 @ Jan 13 2010, 12:37 PM) index.php?act=findpost&pid=1629453
Hello guys, this is my first reply or even post... I was always curious about this AWD vs handbrake condition, so I intentionally parked the with the front wheel on ice and then attempted to spin the front wheels with the parking brake pulled, well guess what, the wheels would not "really" spin at all and I could "feel" the engine was trying to spin the rear wheels !!! On the other hand, I do get this infamous pulsing vibration on smooth roads at 100 to 120 KMH and it does disapear when I then pull the parking brake up til the light comes on. Can anyone explain ??[/b]
I too had this problem by running different kinds of tires from front to back. What tires do you have?
 

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QUOTE (louis1 @ Jan 13 2010, 01:37 PM) index.php?act=findpost&pid=1629453
Hello guys, this is my first reply or even post... I was always curious about this AWD vs handbrake condition, so I intentionally parked the with the front wheel on ice and then attempted to spin the front wheels with the parking brake pulled, well guess what, the wheels would not "really" spin at all and I could "feel" the engine was trying to spin the rear wheels !!! On the other hand, I do get this infamous pulsing vibration on smooth roads at 100 to 120 KMH and it does disapear when I then pull the parking brake up til the light comes on. Can anyone explain ??[/b]

You MUST turn off the DSC!!!!!!!!!!
 

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QUOTE (FORZDA 1 @ Jan 13 2010, 04:03 PM) index.php?act=findpost&pid=1629480
You MUST turn off the DSC!!!!!!!!!![/b]
Hello FORZDA 1, gave that a try last evening, we had a light dusting of snow here in Montréal (Canada) and the streets were slippery, turned the DSC off and still the front wheels won't spin and the engine actually turned the rear wheels and I could smell that heated clutch scent !! I got my four winter tires which I have just installed in early December, they show even wear and have the correct inflation pressure. Is it possible this parking brake feature is not active on Canadian market cars ? Though as I said before the infamous 100 - 120 KMH vibe/resonance discussed on other treads does disapear when I pull the parking brake lever driving on the highway. Any comments or ideas ?
 

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I read somewhere that our cars are only in AWD when it's needed and that most of the time its in full front wheel drive while switching to AWD if the system detects slippage. Is this really the case or is it b.s.?
 

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I hear that it's a constant 95/5 front / back when the fronts have full grip, but not sure that's really the case. The computer does distribute the torque to the rear only after the fronts lose grip. It's SUPPOSED to be a transparent process, but I've caught mine with some pretty substantial front wheel slip before feeling the rears kick in (accelerating hard from a standstill, turning right with gravel under the right front tire). I think the Subaru system is more seamless.
 

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It's been confirmed multiple times that the clutch pack is almost always engaged. This means that there is always some power going to the rear. The only times the rear is fully disconnected is when you are in reverse or when you are at low speeds (~10MPH).

The clutch pack for the rear differential is actuated by a solenoid. The power to the solenoid is sent in pulses with the length of the pulse proportional to the amount of clutch engagement. If you attach a voltmeter into the wire going to this solenoid you can see with your own eyes how engaged the rear diff is. In fact I'm surprised nobody had come out with instructions for displaying this on a gaugepod. Anyways, if you look around YouTube you will find a video where someone has put a voltmeter on the solenoid wire and driven around and monitored it. It clearly shows that the rear is partially engaged nearly all the time and fully engages almost the instant you accelerate or begin driving aggressively.

FYI, the front differential is an open diff, but the ECM uses the brakes to prevent excessive freewheeling (much like the Caliber SRT), the rear diff is a helical torsen limited slip unit almost identical to the one used in the RX-8 (it is considered a very good and robust unit).
 

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QUOTE (gte024h @ Jan 14 2010, 08:08 PM) index.php?act=findpost&pid=1629832
...In fact I'm surprised nobody had come out with instructions for displaying this on a gaugepod. Anyways, if you look around YouTube you will find a video where someone has put a voltmeter on the solenoid wire and driven around and monitored it. It clearly shows that the rear is partially engaged nearly all the time and fully engages almost the instant you accelerate or begin driving aggressively.

FYI, the front differential is an open diff, but the ECM uses the brakes to prevent excessive freewheeling (much like the Caliber SRT), the rear diff is a helical torsen limited slip unit almost identical to the one used in the RX-8 (it is considered a very good and robust unit).[/b]
You should be able to use an gauge that reads 0-5v and just wire tap it in. I'm going to be playing with the AWD system during the spring and will post results, I've got a few ideas :p

I didn't know the ECU controlled the front calipers, I assume this operation only happens during DSC on? Where did this information come from? It's new to me.
 

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QUOTE (louis1 @ Jan 14 2010, 01:41 PM) index.php?act=findpost&pid=1629698
Hello FORZDA 1, gave that a try last evening, we had a light dusting of snow here in Montréal (Canada) and the streets were slippery, turned the DSC off and still the front wheels won't spin and the engine actually turned the rear wheels and I could smell that heated clutch scent !! I got my four winter tires which I have just installed in early December, they show even wear and have the correct inflation pressure. Is it possible this parking brake feature is not active on Canadian market cars ? Though as I said before the infamous 100 - 120 KMH vibe/resonance discussed on other treads does disapear when I pull the parking brake lever driving on the highway. Any comments or ideas ?[/b]
Hmmm? Sounds like you may have a problem with the coupling unit. The pilot clutch may be failed and "stuck" on. It is possible for this type of friction discs to stick together. Noe that there is always some amount of drag on the main clutches as they are a friction-coupled wet-clutch very similar to a motorcycle clutch, so there will always be some small amount of torque applied to the rear drive even with the E-brake on and the DSC off. If all wheels are on ice or other very slippery surface, the rears will likely turn as there is little traction to break the clutch pack friction. However, it should never be enough to pull the rears in on a high(er) traction surface.

I can tell you for a fact that it only takes about 3/4 rotation of the fronts to bring the rears up to full speed(spinning and leaving 4 solid black lines as the rear drifts out of line a bit) lockup when launching HARD. Most of that motion is taking up all the clearances in the front-to-rear drive train. I've only tested the E-brake cutout while on jack stands with all tires off the ground. Another fact is that the e-brake input will disable the pilot clutch (and subsequently the main clutch) and if you pull it hard enough, the rears tires will stop turning and kill the engine at idle. If you give it a bit of throttle, the fronts will continue, although there is a significant drag on the engine which will requires the bit of throttle to overcome.

There is a very good kinematic drawing of the rear coupling in the Mazdaspeed6 Introduction package showing the pilot clutch, the main clutch, and the ball-and-ramp mechanism that actually applies the locking force to the main clutch.

Another fact is that the AWD module, under "normal" conditions applies duty cycle (DC voltage) to the pilot clutch based on the accelerometer inputs WITHOUT any front wheel slippage with DSC on. With DSC off, it reacts to the wheel speed sensors only. If your wheel sensor(s) are bad the TCS/ABS/AWD caution lights should illuminate as they all rely on those wheel sensors. IMO, the AWD system on the Speed6 is very good and solidly designed. There are others that have more left/right torque applicaion variability, but the front/rear power transfer on the Speed6 works VERY well in high performance situations with an experienced driver WITHOUT the DSC on. The trans, PTO, and rear diff will stand up to brutal launches until the inner CV joints on the rear axle fail. They fail due to their relatively small size due to packaging limitations.

I've had mine (Speed6 and many others) on the autocross course and drag strip and it works great. I can't comment on the snow/ice capability as Ive only raced a FWD on the frozen Stockade Lake in the Black Hills of South Dakota.

I can tell you a fact that the rear LSD is the old standard cone-friction type that is VERY good and durable for racing, but it generally applies too much lock to keep the rear wheels in line. Lots of people don't understand that a LSD does NOT help in cornering grip on ice/snow. In fact, it will spin both rear tires which makes the rear of the car slide around where novice drivers need it to follow the front without fail. That is why MOST Speed6 drivers should keep the DSC on at all times. It will limit engine power and apply the brakes to try and keep the rear behind the front and the front steering.

Wow, long post......
 

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QUOTE (OzzmanNT @ Jan 14 2010, 07:24 PM) index.php?act=findpost&pid=1629839
I didn't know the ECU controlled the front calipers, I assume this operation only happens during DSC on? Where did this information come from? It's new to me.[/b]
Another user here posted some scanned Mazda documents which explain how the DSC/TCS system works in detail. I downloaded them and made a PDF if you are interested. It's here. Page 28 begins to explain how the DSC control will apply individual brakes to control wheel spin (even when you are not using the brakes). The second bullet point on page 34 pretty clearly states that it will use the brakes to control "driving wheel slip". The translation is a bit lacking though.
 

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QUOTE (louis1 @ Jan 14 2010, 12:41 PM) index.php?act=findpost&pid=1629698
...as I said before the infamous 100 - 120 KMH vibe/resonance discussed on other treads does disappear when I pull the parking brake lever driving on the highway. Any comments or ideas ?[/b]
If you get a "howling" resonance from the rear at around 60MPH which goes away when you disengage the rear diff, you need to take it to the dealer and get a new diff. I had the same problem from day one with my car and it slowly got louder. At 18,000 miles it was ear piercing if you moved your head just right, so I took it to the dealer. I expected them to void the warranty on the diff because I had the TurbineTech front diff mount, but they called me the next day and said it was covered and they had a new diff in the car the very next week. At 39,000 miles the "howl" has not come back.

If you get a mild low rumble that pulsates slowly (every 5 seconds or so) at cruising speeds, or a low pitched rumble from the rear on hard acceleration, that may just be the clutch pack. I know in my car it gets louder the when there is a difference in air pressure between the front and rear or a difference in tire wear front to rear.

Also, the clutch pack cuts out completely at low speed (around 12MPH) so if you have any binding in the drive train from severely different air pressures or tire wear, when you slow down you'll hear a "clunk" from the rear when you hit ~12MPH (right before you stop). For the longest time I though something was loose back there until I got new tires and set the air pressures, then it went away.
 

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QUOTE (gte024h @ Jan 14 2010, 09:12 PM) index.php?act=findpost&pid=1629851
Another user here posted some scanned Mazda documents which explain how the DSC/TCS system works in detail. I downloaded them and made a PDF if you are interested. It's here. Page 28 begins to explain how the DSC control will apply individual brakes to control wheel spin (even when you are not using the brakes). The second bullet point on page 34 pretty clearly states that it will use the brakes to control "driving wheel slip". The translation is a bit lacking though.[/b]
Thanks! Pretty handy information actually.
 

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ok, so due to some terrible potholes, i've had to drive 170 miles on a spare. Now I've temporally put on winter wheels on front. fronts are 225/40 rears 215/45.

i know this is bad.

i get the rumble from back at 35mph, which disappears with e-brake.

a) did i ruin something already? :(
b) can I drive with awd off switch?
 
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