Mitsubishi 1989-1993 GALANT Service Manual page 310

13-168
FUEL SYSTEM <SOHC-16 VALVE> -
OPERATION
The crankshaft position sensor detects the
l
crank angle (piston position) of each cylinder,
converts it to a pulse signal and inputs it to the
engine control module. The engine control mod-
ule computes the engine speed and the intake
air amount for one stroke and outputs the injec-
tor drive signal and injection command signal
based on this signal.
Power to the crankshaft position sensor is sup-
plied from the ignition switch (IG), and the
ground is located in the engine control module.
A 5V voltage is applied from the engine control
module to the crankshaft position sensor output
terminal, and the crankshaft position sensor
generates a pulse signal as it switches from
OPEN to SHORT (power transistor inside the
sensor switches ON/OFF) between the output
terminal and the ground.
TROUBLESHOOTING HINTS
Hint 1: If unexpected shocks are felt during driving
Hint 2: If the crankshaft position sensor outputs a
Hint 3: If the tachometer reads 0 rpm when the en-
Hint 4: If the tachometer reads 0 rpm when the en-
Hint 5: If the engine can be run at idle even though
TSB Revision
or the engine stalls suddenly during idling,
shake the crankshaft position sensor har-
ness. if this causes the engine to stall, poor
contact of the sensor connector is sus-
pected.
pulse signal when the ignition switch is
turned to ON, (without starting the engine),
the crankshaft position sensor or engine
control module is probably defective.
gine that has failed to start is cranked, faulty
crankshaft position sensor or broken timing
belt is suspected.
gine that has failed to start is cranked, the
primary current of the ignition coil is not
turned on and off. Therefore, troubles in the
ignition circuit and ignition coil or faulty igni-
tion power transistor is suspected.
the crankshaft position sensor reading is out
of specification, troubles are often in other
than the crankshaft position sensor.
[Examples]
(1) Faulty water temperature sensor
(2) Faulty idle air control motor
(3) Poorly adjusted basic idle speed