Engine Coolant Temp Sensor Description; Operation; Removal; Installation - Chrysler Dodge Caravan 2002 Manual

RG
COOLANT RECOVERY PRESS CONTAINER (Continued)
Fig. 6 COOLANT RECOVERY PRESSURE
CONTAINER
1 - COOLANT RECOVERY PRESSURE CONTAINER
2 - COOLANT BYPASS HOSE
3 - OUTLET HOSE
4 - PRESSURE/VENT CAP
ENGINE COOLANT TEMP
SENSOR
DESCRIPTION
The engine coolant temperature sensor threads
into a coolant passage in the cylinder head (Fig. 7).
New sensors have sealant applied to the threads.

OPERATION

The coolant temperature (ECT) sensor is a nega-
tive temperature coefficient (NTC) thermistor (resis-
tance varies inversley with temperature). This means
at cold tempertures its resistance is high so the volt-
age signal will be high. As coolant temperture
increases, resistance decreases and the signal voltage
will be low. This allows the sensor to provide an ana-
log voltage signal to the ECM.

REMOVAL

WARNING: DO NOT REMOVE OR LOOSEN THE
COOLANT PRESSURE/VENT
BLOCK DRAIN PLUGS, OR THE DRAINCOCK WHEN
THE SYSTEM IS HOT AND UNDER PRESSURE
BECAUSE SERIOUS BURNS FROM THE COOLANT
CAN OCCUR.
CAP, CYLINDER
Fig. 7 COOLANT TEMPERATURE SENSOR
LOCATION
1 - EGR SOLENOID
2 - UPPER RADIATOR HOSE
3 - COOLANT TEMPERATURE SENSOR
4 - INTAKE MANIFOLD INLET
5 - INTAKE MANIFOLD/CYLINDER HEAD COVER
(1) Drain the cooling system. (Refer to 7 - COOL-
ING/ENGINE/COOLANT
DURE)
(2) Disconnect coolant temperature sensor electri-
cal connector (Fig. 8).
(3) Remove coolant temperature sensor from cylin-
der head (Fig. 8).

INSTALLATION

(1) Install coolant temperature sensor in cylinder
head (Fig. 8).
(2) Connect coolant temperature sensor electrical
connector (Fig. 8).
(3) Refill the cooling system. (Refer to 7 - COOL-
ING/ENGINE/COOLANT
DURE)
(4) Connect the negative battery cable.
ENGINE 7a - 19
- STANDARD PROCE-
- STANDARD PROCE-