Mitsubishi Eclipse Workshop Manual page 123

FUEL
-
On-vehicle Inspection
of
MPI
Components
13-59
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ENGINE COOTANT TEMPERATURE SENSOR
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OPERATION
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The engine coolant temperature sensor converts the engine coolant
temperature
into a voltage
and
inputs it to the engine control unit, which then controls the fuel injection rate and fast idle speed wtren
the engine is cold
based
on the input
signal.
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The 5V power in the engine control unit is supplied via
a
resistor in
the
unit
to the
engine coolant
temperature sensor. Through the sensor which is a kind of resistor,
it is grounded in the engine control
unit. The engine coolant temperature sensor resistor has such characteristic that its resistance decreases
as the engine coolant temperature
rises.
o
The
engine coolant temperature sensor terminal voltage increases or decreases
as
the sensor resistance
increases or decreases. Therefore, the engine coolant temperature sensor terminal voltage changes wrlr
the engine coolant temperature, decreasing
as
the temperature
rises.
TROUBTESHOONNG HINTS
lf the fast idle speed is inadequate or the engine emits dark smoke during engine warm up operation. the
engine coolant temperature sensor is often faulty.
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o
Engine coolant
temperature
rtzata
Engine coolant temperature
r.t
loo.
Equipment
sic
connector
Irl
TJ
Lvl
Harness side
connector
@
Mitsubishi Motors Corporation
Apr.
1991
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