Daewoo NUBIRA, User Manual

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ENGINE COOLING 1D – 19
DAEWOO V–121 BL4
CAUTION : If a fan blade is bent or damaged in any
way, no attempt should be made to repair or reuse the
damaged part. A bent or damaged fan assembly
should always be replaced with a new one. Failure to
do so can result in personal injury.
The cooling fans are mounted behind the radiator in the
engine compartment. The electric cooling fans increase
the flow of air across the radiator fins and across the con-
denser on air conditioned (A/C) equipped vehicles. This
helps to speed cooling when the vehicle is at idle or moving
at low speeds.
The main fan size is 300 mm (11.8 inches) in diameter with
five blades to aid the air flow through the radiator and the
condenser. An electric motor attached to the radiator sup-
port drives the fan.
A/C models have two fans – the main fan and the auxiliary
fan. The auxiliary fan is 300 mm (11.8 inches) in diameter.
A/C Off or Non–A/C Model
S
The cooling fans are actuated by the powertrain
control module (PCM)/engine control module
(ECM) using a low–speed cooling fan relay and a
high–speed cooling fan relay. On A/C–equipped
vehicles, a series/parallel cooling fan relay is also
used.
S
The PCM/ECM will turn the cooling fans on at low
speed when the coolant temperature reaches 93
³
C
(199
³
F) and at high speed when the coolant tem-
perature reaches 97
³
C (207
³
F).
S
The PCM/ECM will change the cooling fans from
high speed to low speed at 94
³
C (201
³
F) and will
turn the cooling fans off at 90
³
C (194
³
F).
A/C ON
S
The PCM/ECM will turn the cooling fans on at low
speed when the A/C system is on. The PCM/ECM
will change to high speed when the coolant temper-
ature reaches 115
³
C (239
³
F) or the high side A/C
pressure reaches 1 882 kPa (273 psi).
S
The cooling fans will return to low speed when the
coolant temperature reaches 112
³
C (234
³
F) and
the high side A/C pressure reaches 1 448 kPa (210
psi).
COOLANT TEMPERATURE SENSOR
The coolant temperature sensor (CTS) uses a thermistor
to control the signal voltage to the powertrain control mod-
ule (PCM)/engine control module (ECM).
ENGINE COOLANT TEMPERATURE
SENSOR
The engine coolant temperature sensor controls the nstru-
ment panel temperature indicator. The engine coolant
temperature sensor is located on the intakemanifold near
the throttle body on an SOHC engine, and on the cylinder
head under the intake manifold on a DOHC engine.
ENGINE BLOCK HEATER
The vehicle is designed to accept an engine block heater
that helps to warm the engine and to improve starting in
cold weather. It also can help to reduce fuel consumption
while a cold engine warms up.
The engine block heater is located under the intake man-
ifold and uses an existing expansion plug for installation.
Contact your Daewoo Dealer for further information or
installation.