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Speed, lead from ABS

Speed, lead from ABS





The ABS control module sends a speed signal to pin 64 of the Trionic T7's control module. The signal is a square wave which varies between 0 V and B+ 29 times per wheel rotation. This speed signal is used to:


determine, on manual gearboxes, which gear is used at the moment. This allows torque limitation in gears R and 1 and activation of the fuel shut-off in gears 2, 3, 4 and 5.

activate speed limitation by limiting the maximum mass air flow/combustion at 240 km/h.

prevent adaptation of idle speed control when the car is moving.




Diagnostics


If there is no speed signal, diagnostic trouble code P0502 will be generated.

The speed (bus from MIU) is used as a substitute value.


System reaction to a fault

Cruise control is blocked.