Processing of signals from a crankshaft sensor

A method whereby a processing module (6) processes signals from a crankshaft sensor (1) in order to determine the position of an internal combustion engine upon a starting of said engine following a stopping thereof, said crankshaft sensor comprising a crankshaft wheel (2) comprising a determined number of teeth and at least one index (4) allowing a position in the revolution to be identified, said sensor being able, in combination with a processing device (5) for processing said signals, to determine the position of the crankshaft and direction of rotation of the crankshaft, from said signals comprising forwards-running and backwards-running square waveforms,

• the method comprising:
• detection of a stopping of said internal combustion engine, and,
• if the last square waveform received by the processing device (5) before the stopping of the engine corresponds to the engine rotating backwards:
• suspension of the transmission to the processing device (5) of an “engine stopped” status signal, and then
• simulation by the processing module (6) and transmission to the processing device (5) of a backwards-running square waveform (8),
• simulation by the processing module (6) and transmission to the processing device (5) of a forwards-running square waveform (9), leading to a detection by the processing device (5) that the crankshaft is running forwards, and,
• following the transmission of the two simulated square waveforms (8, 9) to the processing device (5), the lifting of said suspension and the transmission of the “engine stopped” status signal to the processing device (5).