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Engine rpm

Engine rpm



The TC/ABS control module receives information on the current engine rpm on pin 30. It supplies the lead with current and the Trionic grounds the lead twice per engine revolution. The TC/ABS control module uses the frequency to calculate current engine rpm. The signal is a square wave of about 23 Hz at idling speed and about 83 Hz at 2500 rpm.

The control module uses engine rpm information for:


Calculating the current drive wheel torque. Engine rpm and car speed are used to calculate the current ratio. When engine torque and the current ratio are known, the control module can calculate the drive wheel torque. Drive wheel torque is used to calculate the magnitude of brake/engine torque limitation during TCS modulation.


Diagnostics

Diagnostic trouble code C0236 will be set in the event of a break/short circuit in the engine rpm lead when the engine is started and the TCS function will be disabled at the same time as the TCS OFF lamp lights up.