Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Sfi system / Crankshaft position sensor ”a”
circuit / Circuit description
Toyota Corolla (E120): Circuit description
The crankshaft position sensor (ne signal) consists of a magnet, iron core and pickup coil.
The ne signal plate (crankshaft position sensor plate) has 34 teeth and is installed on the crankshaft. The ne signal sensor generates 34 signals for each engine revolution. This sensor monitors a plate (timing rotor) located on the crankshaft timing pulley and is used by the ecm to detect crankshaft angle and engine speed (rpm/ne). As the crankshaft timing pulley rotates through an engine revolution, this sensor communicates the rotation of the ne signal plate as a pulse signal to the ecm. Based on the signal, the ecm controls fuel injection time and ignition timing.
Reference: inspection using the oscilloscope.
Hint
: the correct waveform is as shown on the left.
Monitor description
If there is no signal from the crankshaft sensor despite the engine revolving, the ecm interprets this as a malfunction of the sensor.
Monitor strategy
Typical enabling conditions
Typical malfunction thresholds
Wiring diagram
Other materials:
Seat belt pretensioners (front seats)
The pretensioners help the seat belts to quickly restrain the occupants by retracting
the seat belts when the vehicle is subjected to certain types of severe frontal
or side collision.
The pretensioners do not activate in the event of a minor frontal impact, a minor
side impact, a rear impact ...
Inspection procedure
Hint:
read freeze frame data using the hand-held tester or the obd ii scan tool.
Freeze frame data records the
engine conditions when a malfunction is detected. When troubleshooting, it is
useful for determining whether
the vehicle was running or stopped, the engine was warmed up or not, the ...
Safety information for children
Observe the following precautions when children are in the vehicle.
Use a child restraint system appropriate for the child, until the child becomes
large enough to properly wear the vehicle’s seat belt.
● It is recommended that children sit in the rear seats to avoid accidental contact
...