Polaris RANGER XP 1000 2018-2019, Service Manual

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9929399 R01 - 2018-2019 RANGER XP/ CREW 900/1000 Service Manual
© Copyright Polaris Industries Inc.
ENGINE COOLANT TEMPERATURE SENSOR (ECT)
OPERATION OVERVIEW
Mounted in the cylinder head, the engine temperature
sensor measures coolant temperature. The engine
temperature
sensor is a Negative Temperature
Coefficient (NTC) type sensor, as the temperature
increases the resistance decreases.
Coolant passes through the cylinder head and by the
sensor probe, varying a resistance reading which is
relayed to the ECU. This signal is processed by the ECU
and compared to its programming for determining the
fuel and ignition requirements during operation. The ECU
also uses this signal to determine when to activate the
cooling fan during operation.
ECT SENSOR TEST
To quickly rule out other components and wiring related
to the ECT, disconnect the harness from the ECT sensor
and start the engine. After a few seconds, the fan should
turn on and the “Check Engine” indicator should display
on the instrument cluster. This indicates all other
components are working properly.
Refer to “Coolant Temperature Sensor”page 11.25 for
additional ECT sensor information. Polaris dealers can
test the sensor by using Digital Wrench® Diagnostic
Software (dealer only).
ECT Sensor Resistance Readings
TEMPERATURE °F (°C)
RESISTANCE
68 °F (20 °C)
2.5k Ω ± 6%
86 °F (30 °C)
1.7k Ω ± 6%
104 °F (40 °C)
1.2k Ω ± 6%
122 °F (50 °C)
834 Ω ± 6%
140 °F (60 °C)
596 Ω ± 6%
158 °F (70 °C)
435 Ω ± 6%
176 °F (80 °C)
323 Ω ± 6%
194 °F (90 °C)
243 Ω ± 6%
212 °F (100 °C)
186 Ω ± 6%
FUEL SYSTEM