Coherence Diagnosis

Coherence Diagnosis
The following diagnoses check the coherence between two redundant acquisitions:

Throttle position sensors
For safety reasons, the system has 2 sensors for throttle position. Signals from the two sensors are compared and must be within a given tolerance.
2 errors can be raised:
- Small discrepancy: it is here difficult to identify which sensor is wrong. For safety reasons, the system selects the highest one
- Large discrepancy: a plausibility check is performed with engine speed and mass air flow in order to define which sensor check gives the wrong information.

Pedal position sensor
In case of discrepancy between the 2 pedal position sensors, the channel giving the smallest value is then selected (torque request will then be naturally under-estimated).

Brake switches
It is checked if the 2 brake switches give different information, an error is raised. Cruise control is then inhibited.