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Request for engine torque

Request for engine torque



The engine torque can vary between -100 Nm and +400 Nm. Negative values indicate engine braking.

The TC/ABS control module sends information with a request for torque to the engine control module. This information is sent via the P-bus. The request can vary between +10 Nm and +400 Nm. 400 Nm will be requested when TC regulation is inactive. Information is used in the engine control module together with other information in order to supply the correct torque to the drive wheels. See also the description of the engine control module.

Torque request during wheelspin

If one of the drive wheels exceeds the specified limit of wheel spin, the TC/ABS control module will request a lower engine torque from the engine control module. The engine control module will then regulate the throttle in the throttle body to provide a rapid reduction of torque. The boost pressure will subsequently be reduced if necessary.

Torque request during engine braking

During engine braking, it is possible that the speed of the front wheels becomes lower than the speed of the rear wheels. If the vehicle speed exceeds 25 km/h and the engine torque is below -50 Nm, the TC/ABS control module will request increased torque to maintain directional stability.

There are two levels for the request for increased torque


• If the speed of the front wheels is between 2 and 5 km/h lower than the rear wheels, the TC/ABS control module will request an engine torque of -10 Nm.

• If the speed of the front wheels is more than 5 km/h lower than the rear wheels, the TC/ABS control module will request an engine torque of +10 Nm.


Higher torque is not requested at speeds below 25 km/h.