GF42.35-P-0001F Electronic Traction System (ETS), Function
GF42.35-P-0001F Electronic Traction System (ETS), Function
MODEL 463.243 /244 /246 /247 /249 /250 /254 ## as of 127357 as of 1.9.01 up to 31.5.12, 463.270 /271 up to 31.5.12, 463.309 /322 /323 /332 /333 ## as of 127357 as of 1.9.01 up to 31.5.12
- with CODE (BB3) Electronic Stability Program (ESP)
MODEL 463.248 ## as of 127357 as of 1.9.01 up to 31.5.12
- with CODE (BB3) Electronic Stability Program (ESP)
- except CODE (979) Special protection version
1 General
^ The "electronic traction system (ETS)" functionality is integrated as a software module in the ESP and BAS control module (N47-5).
^ The electronic traction system (ETS),
- is an electronic system which improves the starting-off and accelerating performance as well as the cornering stability of the vehicle particularly on road surfaces with different levels of grip.
- and it replaces, in part, the function of both the locking differential at the front axle / rear axle and the transfer case.
^ It is not involved with engine management control.
2 Function in normal mode
^ In the normal operating mode, when none of the wheels are slipping to the extent that slip control is required, the ETS is in the "ready for operation" mode and does not intervene in the driving dynamics of the vehicle.
^ The system must be free of faults for the ETS to be in the "ready for operation" mode.
3 Function in control mode
^ If the prerequisites for activation of the ETS control mode occur, e.g. slip at one or more of the 4 wheels, the ETS is activated automatically.
The slip of the wheels is controlled by braking the affected wheel as part of controlling the braking torque.
^ The ETS is no longer active at speeds in excess of approx. 60 km/h.
^ The ETS is still active even if the ESP is switched off.
^ Braking torque control at the front axle
If one of the front wheels begins to spin, the wheel is braked until the calculated drive slip is reached.
If the second front wheel also spins, this wheel is braked in the same way as the first front wheel provided that neither or only one of the rear wheels is controlled.
^ Braking torque control at the rear axle
If one of the rear wheels begins to spin, the spinning wheel is braked by the appropriate wheel brake until the calculated drive slip is obtained. The other rear wheel can therefore transfer a drive torque that is higher by the amount of the braking torque. The drive torque also increases at the front wheels according to the torque distribution in the transfer case (locking differential effect).
The brake pressure is increased at the second rear wheel from a vehicle speed of 10 km/h. The brake pressure level of the spinning rear wheel is reached at a speed of 40 km/ h. This prevents the second rear wheel from spinning and to some extent also prevents the vehicle from breaking away.
- If the second rear wheel also spins, this wheel is also controlled in the same way as the first rear wheel up to a speed of 10 km/h. From a speed of 10 km/h onwards the lower of the two brake pressures is matched to the higher pressure (synchronized pressure build-up) in order to prevent yaw motion due to different drive torques at the rear axle wheels.
