SFI SYSTEM


  1. CONSTRUCTION


    1. A pick-up coil type crank position sensor is used. The No. 1 crankshaft position sensor plate of the crankshaft consists of 34 teeth, with 2 teeth missing. The crank position sensor outputs the crankshaft rotation signals every 10°, and the missing teeth are used to determine the top-dead-center.

    2. A Magnetic Resistance Element (MRE) type cam position sensor (No. 1 crank position sensor) is used. To detect the camshaft position, each timing rotor on the intake and exhaust camshafts is used to generate 6 (3 high output, 3 low output) pulses for every 2 revolutions of the crankshaft.

      A00XRFQC01
      *1 Crank Position Sensor *2 No. 1 Crankshaft Position Sensor Plate
      *3 Cam Position Sensor (No. 1 Crank Position Sensor) (Intake) *4 Cam Position Sensor (No. 1 Crank Position Sensor) (Exhaust)
      *5 Timing Rotor (Camshaft) - -
      A00XRJYE01

    3. The MRE type cam position sensor (No. 1 crank position sensor) consists of an MRE, a magnet and a sensor. The direction of the magnetic field changes due to the differing shape (protruding and non-protruding portions) of the timing rotor, which passes by the sensor. As a result, the resistance of the MRE changes, and the output voltage to the ECM changes to high or low. The ECM detects the camshaft position based on this output voltage.

    4. The differences between the MRE type cam position sensor (No. 1 crank position sensor) and the pick-up coil camshaft position sensor used on conventional models are as follows:

      Item Sensor Type
      MRE Pick-up Coil
      Signal Output Constant digital output starts from low engine speeds. Analog output changes with the engine speed.
      Camshaft Position Detection Detection is made by comparing the NE signals with the high/low output switch timing due to the protruding/non-protruding portions of the timing rotor, or made based on the number of the input NE signals during high/low outputs. Detection is made by comparing the NE signals with the change of waveform that is output when the protruding portion of the timing rotor passes.
      A00XR8TE03