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Engine torque limitation

Engine torque limitation



The TC/ABS control module sends a torque limitation signal to the Trionic. The signal is a 100 Hz PWM and goes out from pin 13 of the control module.

The different pulse ratios have the following meanings:

Pulse ratio [%] Signification of the signal
9-82 %

To limit the engine torque between 0 Nm and 350 Nm. Trionic converts Nm to mg air/combustion. The value constitutes the maximum air mass/combustion that the TC/ABS control module allows when TCS is active and wheel spin exceeds the permitted limit.

82-84 %

No slip and TC/ABS control module programmed for 4-cylinder engine.

84-86 %

No slip and TC/ABS control module programmed for 6-cylinder engine.

86-88 %

Increase torque to 0 Nm. Sent when slip occurs in connection with engine braking and the vehicle speed exceeds 25 km/h (15.5 mph). The vehicle speed and amount of slip determine whether the control module selects 0 Nm or 10 Nm. If the slip is low, 0 Nm is selected and if it is high, 10 Nm is selected.

88-90 %

Increase torque to 10 Nm. Sent when slip occurs in connection with engine braking and the vehicle speed exceeds 25 km/h (15.5 mph). The vehicle speed and amount of slip determine whether the control module selects 0 Nm or 10 Nm. If the slip is low, 0 Nm is selected and if it is high, 10 Nm is selected.



Diagnostics

Trionic monitors the Engine Torque Limitation function. If there is a break/short circuit in the lead for engine torque, Trionic will send a pulse ratio of 96% as an engine torque signal, whereby the TC/ABS control module will generate DTC C0241. The TCS function will be disengaged and the TCS OFF lamp will go out.