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Why is my all wheel drive turning off while I'm driving and how come I can get it to stay on!
 

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It will turn off after a certain speed. The Trax isn't a true AWD even if the logo is on the tailgate. It is simply a rear wheel assist when front wheel slip. As soon as there's no slippage it disengages. If you are in constant slippage you are driving to fast for existing condition and the rear differential may heat up and disengage.
 

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It will turn off after a certain speed. The Trax isn't a true AWD even if the logo is on the tailgate. It is simply a rear wheel assist when front wheel slip. As soon as their si no slippage it disengages. If you are in constant slippage you are driving to fast for existing condition and the rear differential may heat up and disengage.
It will turn off after a certain speed. The Trax isn't a true AWD even if the logo is on the tailgate. It is simply a rear wheel assist when front wheel slip. As soon as their si no slippage it disengages. If you are in constant slippage you are driving to fast for existing condition and the rear differential may heat up and disengage.
I wasn't going fast was in town just turned a corner when it kicked on
 

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If your front wheels slipped Stabilitrak would have kicked the rear differential on then turn it off when all wheels are turning the same speed.
 

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It will turn off after a certain speed. The Trax isn't a true AWD even if the logo is on the tailgate. It is simply a rear wheel assist when front wheel slip. As soon as there's no slippage it disengages. If you are in constant slippage you are driving to fast for existing condition and the rear differential may heat up and disengage.
I’m curious as to where you found this info. AWD is designed for operation at all speeds; especially high speed. My understanding is that most, if not all systems, maintain an 80/20% power distribution until more needs to be redirected due to traction loss. Now, my manual does say that it will shut down the AWD if it becomes overheated. But that spinning and overheating is only going to happen if you’re stuck and trying to spin and rock your way out. Or perhaps there are different designs for the US and Canada versions???
3773
 

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as required,

The rear differential clutch control module provides power and ground switching circuits to the rear
drive clutch coil. The coil receives current from the rear differential clutch control module through
PWM high side driver, and converts that signal into torque through the clutch to the rear tires when all wheel drive (AWD) is requested.
 
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So how do you know when the AWD is on or off while driving?
I think it’s always on. That’s the entire purpose of AWD vs 4WD. The only time it gets disabled (per the manual) is when it overheats from excessive spin, such as when stuck.
 

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It's always "OFF". The system is always on, it's called stabilitrak in conjunction with PWM and traction control. The text in post #6 was taken right out of the service manual. The rear differential is engaged on demand as requested.


3784
 

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StabiliTrak and AWD are NOT synonymous. Stabilitrak is now standard on every GM car; RWD, FWD, AWD, and 4WD. It works as you say; as needed, only when needed to keep the vehicle on the intended trajectory. The AWD is ALWAYS ON, even at 85mph. StabiliTrak is always on too, but in kind of a standby mode, waiting for the cars trajectory to go amiss. StabiliTrak manipulates what you’ve highlighted above, but also works the brakes and steering to maintain the desired trajectory. It’s similar to traction control, but TC only works the brakes. What is StabiliTrak in Cars? | Auto.com
 

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For the last time. Your Trax is front wheel drive until the PWM activates the clutch for the rear differential when needed.
 

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For the last time. Your Trax is front wheel drive until the PVM activates the clutch for the rear differential when needed.
You need to pay a visit to your dealer’s shop. StabiliTrak is not a name GM gave to their AWD system. But you go right ahead and believe that. But stubbornness isn’t giving anybody answers they’re looking for.
 

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Close my account. There’s enough fake info on the web without having to put up with know-it-alls spreading misinfo here.
 

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Don't get mad. lol. I'm not making this up, I'm taking the info right from the GM service manual. But you can try lifting the back wheels, blocking the front wheels pulling it in drive and I garantie you the rear wheels won't turn. Don't go away, nothing wrong with a good discussion. Good dialogue is what forums are for, that is the way we discover the truth. Feel free to paste your findings that this is an all time AWD an I will bow and acknowledge. I've been wrong before, I'm just going by GM's manual.

I had the driveshaft off of my Trax all of last summer didn't notice any difference in mileage at all. Seems to me if it was active 100% of the time it would have effect on mpg.

The rear drive axle system operates as follows:
The system distributes torque to the rear wheels to enhance traction and improve vehicle
handling performance.
The all wheel drive (AWD) clutch assembly contains an electromagnetic coil, primary clutch, a
ball cam, a secondary clutch, and a rear differential clutch control module.
The rear differential clutch control module uses wheel speeds, steering angle, lateral
acceleration, yaw, chassis control intervention, and other signals to determine the torque to be
applied. This data is transmitted via the vehicles Controller Area Network (CAN) from other
modules and sensors in the vehicle.
The driver information center can display two messages for the Rear Drive Axle system.
Service All Wheel Drive or code 73 and AWD Off or code 173. When these messages are
displayed, the system is disabled and the vehicle will default to 2WD.
If the vehicle is being driven very aggressively or an unexpected tire size has been used, the
AWD Off or code 173 message will be displayed in the driver information center. This should
not result in the replacement of rear differential clutch control module.
The AWD Off or code 173 message will be displayed in the driver information center if the minispare
tire or a very small sized tire has been installed. This should not result in the replacement
of rear differential clutch control module.
The torque transfer to the rear wheels is controlled by the rear differential clutch control module
which sends current to the electromagnet coil in the clutch. The coil applies a load on the
primary clutch which rotates the ball cam loading the secondary clutch. The secondary clutch
applies the torque from the drive shaft, driving the rear wheels. Safe current range is between
0-6.0 A. If the current is out of the specified range, a DTC will be set, and the driver information
center will display the Service AWD or code 73 message.
The rear differential clutch control module has an internal temperature sensor, which will
maintain consistent and continuous temperature compensation for torque transfer from -40°C to
+120°C. When the temperature of the module is determined to be beyond its limits, the rear
differential clutch control module will temporarily disable the rear drive system and the driver
information center will display the AWD Off or code 173 message. When the temperature of the
module is back within the limits, the rear differential clutch control module will enable the rear
drive system.
The rear differential clutch control module monitors the outside air temperature maintaining
consistent and continuous temperature compensation for torque transfer from -20°C (-4°F) to
100°C (212°F).
Voltage to the module is between 9-16 V. The module will set a low voltage DTC and a high
voltage DTC to indicate voltage value out of range.
 

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Don't get mad. lol...
First off, apologies; a rough week left me a bit moody. BTW, what year do you have? Mine’s a 2019, though I doubt there are significant differences.

I'm not making this up, I'm taking the info right from the GM service manual.
I don’t think you’re making anything up; misinterpreting, maybe (maybe not), TBD.

But you can try lifting the back wheels, blocking the front wheels pulling it in drive and I garantie you the rear wheels won't turn.
I’m not so sure about that test. I don’t think the computer would direct any torque to the rear because both rear wheels are free-spinning; no traction. (Although, ironically, that's precisely where a standard diff would send the power, to the tire that freely spins without traction.)

Service All Wheel Drive or code 73 and AWD Off or code 173. When these messages are displayed, the system is disabled and the vehicle will default to 2WD. If the vehicle is being driven very aggressively or an unexpected tire size has been used, the AWD Off or code 173 message will be displayed in the driver information center. This should not result in the replacement of rear differential clutch control module. The AWD Off or code 173 message will be displayed in the driver information center if the minispare tire or a very small sized tire has been installed. This should not result in the replacement of rear differential clutch control module. The torque transfer to the rear wheels is controlled by the rear differential clutch control module which sends current to the electromagnet coil in the clutch. The coil applies a load on the primary clutch which rotates the ball cam loading the secondary clutch. The secondary clutch applies the torque from the drive shaft, driving the rear wheels. Safe current range is between 0-6.0 A. If the current is out of the specified range, a DTC will be set, and the driver information center will display the Service AWD or code 73 message. The rear differential clutch control module has an internal temperature sensor, which will maintain consistent and continuous temperature compensation for torque transfer from -40°C to +120°C. When the temperature of the module is determined to be beyond its limits, the rear differential clutch control module will temporarily disable the rear drive system and the driver information center will display the AWD Off or code 173 message. When the temperature of the module is back within the limits, the rear differential clutch control module will enable the rear drive system. The rear differential clutch control module monitors the outside air temperature maintaining consistent and continuous temperature compensation for torque transfer from -20°C (-4°F) to 100°C (212°F). Voltage to the module is between 9-16 V. The module will set a low voltage DTC and a high voltage DTC to indicate voltage value out of range.
What all the above screams at me is...under which conditions that the AWD will be disabled. More importantly, that whenever it is disabled, “AWD Off or code 173 message will be displayed in the driver information center”. The only time I’ve seen it is when it briefly flashes after initial start.

One final thought...if GM was marketing an AWD system that really wasn’t, don’t you think their lawyers would have some fraud concerns? I mean, as it is, you can’t even by a car from them without their lawyers plastering warning labels all over the interior.
 

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I’m not so sure about that test. I don’t think the computer would direct any torque to the rear because both rear wheels are free-spinning; no traction.
I think that test should have all four wheels up to see what turns during idle. I may just try that during my next oil change.
 

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Well then the module will detect front wheel slippage and activate the rear differential. Had it on a hoist when I re-installed the new driveshaft. Started it and put it in drive, a few seconds in, all wheels were turning. So I knew all was well.
 

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Okay, I’m on board with that. But what part of that manual that you posted says AWD is completely disengaged when there is no slippage (as opposed to just minimizing the % of torque being sent to the rear when unnecessary)?
 

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The way I read it, it says the rear differential module will actuate the clutch as requested. ( and converts that signal into torque through the clutch to the rear tires when all wheel drive (AWD) is requested. ) If the clutch isn't enabled it should be free wheeling. When I had the driveshaft off last summer I noticed absolutely no difference in driveability except when taking off too rapidly on loose stuff or small gravel and I would get wheel spin forever, where with the driveshaft in, it will spin a second or 2 until the module detects differences between front and rear wheel speed and slam the rear diff in action. Sometime it makes a nice loud bang when it is enabled. I never hear it disable.
 
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