Position Sensor Crankshaft
The sensor consists of four hall sensors, one permanent magnet and internal electronics. The sensor has different signal characteristics depending on the crankshaft's direction of rotation.
The signal to the engine control module (ECM) is a quadratic pulse between approx. 0.5 V and 4.5 V. Increased rotation speed gives increased frequency with fixed timed low signal.
During forward rotation the time period for the low signal is 45 μs (1) and at backwards rotation 90 μs (2). The engine control module (ECM) stores the engine position during the current driving cycle. This means that the engine control module (ECM) knows which cylinder is next in turn for injection and ignition at the next start, after the engine has been switched off during Start/Stop.
The engine can therefore be started without having to search for a synchronizing position between crankshaft and camshafts. This gives shorter starting phases with reduced load on the battery and starter motor, especially important when starting during Start/Stop sequence. If the driving cycle is interrupted the stored crankshaft position also disappears from the engine control module (ECM). The crankshaft position sensor's signal is also used for misfire diagnosis.
The sensors for the exhaust and inlet camshafts are identical. The sensor consists of one hall sensor, one permanent magnet and internal electronics. The sensor has only one type of signal characteristic, i.e. the engine control module (ECM) cannot identify the direction of rotation. The signal is a quadratic pulse between approx. 0.5 V and 4.5 V. High signal corresponds to "peak" on the trigger wheel, and "valley" corresponds to low signal.