2008 Polaris Sportsman 700/800/700 X2 EFI Service Manual, Page 130Get this manual
FUEL INJECTION ENGINE TEMPERATURE SENSOR
Operation Overview
Mounted on the cylinder, the engine temperature sensor measures coolant temperatureThe engine temperature sensor is Negative Temperature Coefficient (NTC) type sensor, as the temperature increases the resistance decreasesEngine Temperature Sensor To quickly rule out other components and wiring related to the ETS, disconnect the harness from the ETSThe fan should turn on and HOT' should indicate on the instrument clusterThis indicates all other components are working properlyRefer to Chapter 10 for ETS testingPolaris dealers can also test the sensor by using the Polaris Digital Wrench Software (dealer only)Refer to the Digital Wrench Software Manual for more information
Engine Temperature Sensor Test
Table 4-1: ETS Resistance Readings TEMPERATUREC) 68 (20 C) 212 (100 C)
RESISTANCE
Refer to Chapter 10 for testingStandard resistance readings according to temperature: Coolant passes through the cylinder and by the sensor probe, varying resistance reading which is relayed to the ECUThis signal is processed by the ECU and compared to it's programming for determining the fuel and ignition requirements during operationThe ECU also uses this signal to determine when to activate the fan during operationIf for any reason the engine temperature sensor circuit is interrupted, the fan will default to "ON"