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:
On–vehicle inspection
1. Inspect cooling system for leaks
Caution:
to avoid the danger of being burned, do not remove the radiator
cap while the engine and radiator are still hot, as fluid
and steam can be blown out under pressure.
fill the radiator with coolant and attach a radiator cap tester.
...
Do-it-yourself service precautions
If you perform maintenance
by yourself, be sure to follow
the correct procedure
as given in these sections.
Maintenance
WARNING
The engine compartment contains
many mechanisms and fluids that
may move suddenly, become hot,
or become electrically energized.
To avoid death or serious injury,
obser ...
Checking the engine coolant
The coolant level is satisfactory
if it is between the "MAX" and
"MIN" lines on the reservoir
when the engine is cold.
Reservoir
"MAX" line
"MIN" line
If the level is on or below the "MIN"
line, add coolant up to the "MAX"
line.
■Coolant selection
Only use "Toyota Super Long Life
Coolant" or ...