Originally Posted by Blown7
No traction control is good for the application I'm reworking. Eliminating ESP has multitudes of benefits, namely disabling throttle control.
i'm not sure what your doing , but as per the fsm , it seems the traction control that controls the ETC not the ESP system.
ALL-SPEED TRACTION CONTROL
Traction control systems sense impending wheel spin based on a model of the rate of change of wheel speed under
normal traction conditions. The All-Speed Traction Control uses signals from the same wheel speed sensors as ABS
to determine when to apply the brakes to one or more wheels and when to reduce engine torque output using the
electronic throttle control (ETC) to prevent wheel slip during acceleration
. Throttle control makes the vehicle less
reliant on brake application alone to maintain traction, increasing the operating speed range and more closely modulates
speed, resulting in smoother operation. With All-Speed Traction Control reducing engine torque as well as
applying the brakes, it is possible to achieve almost seamless torque application at the wheels.
If the wheel slip is severe enough to require throttle intervention, All-Speed Traction Control will reduce engine
torque and sometimes upshift the transmission to avoid the condition. In milliseconds, All-Speed Traction Control
interrogates the engine control system to determine the current torque output, determines how much the torque
output the current conditions will allow, and signals this requirement to the engine control system, which reduces the
torque by partially closing the throttle. With execution of the torque reduction, the brake system reduces brake pressure
to make the transition smooth, while maintaining forward progress. By reducing engine power, braking effectiveness
is maintained and the system can operate throughout the normal vehicle speed range. That is why the
system is identified as providing “all-speed” traction control.
With AWD, where front-wheel slip can occur, the degree of throttle intervention is relatively less than with rear-wheel
drive. The difference in speed capability and the degree of throttle intervention between rear-wheel drive and allwheel
drive is due to the fact that non-driven front wheels on a rear-wheel drive vehicle give the system an accurate
vehicle speed reference on which to base responses. With AWD, the possibility that the front wheels may also be
slipping makes appropriate corrective action more difficult to determine, thus limiting the effective speed range. Offsetting
this is the fact that loss of traction is less likely with AWD because torque is transmitted through all four
wheels to begin with. In actual driving situations on snow or ice, the rear-wheel drive and AWD systems respond in
essentially the same way up to the 45 mph (72 km/h) limit of the AWD system.
When severe wheel slippage is detected (as on snow-covered roads), the Winter Mode feature of All-Speed Traction
Control causes the transmission to up-shift to higher gears at lower speeds than normal. Once a slippery launch
condition is detected, the transmission will remain in Winter Mode for a minimum of three minutes. After that, if the
road is providing normal traction, the system returns to providing normal up-shifts.