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 Mazdas 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-7s 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-7s 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 engines power output until the wheel spin stops.
Please feel free to ask questions, I'll help as best I can.
Here is the explanation right out of the Mazda training manual:
"The CX-7 is equipped with Mazdas 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-7s 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-7s 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 engines power output until the wheel spin stops.
Please feel free to ask questions, I'll help as best I can.