Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

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Link: lemon-manuals.la or lemon-manuals.org.ua

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Coolant Temperature Sensor/Switch (For Computer): Description and Operation


The coolant temperature sensor is a thermistor which relays engine coolant temperature information to the ECM micro processor. This temperature information is used to determine when the system is ready to enter the closed loop mode of operation. The information from this sensor is also used to modify the open loop duty cycle.