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

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

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

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

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

Coolant Temperature Sensor:




Engine Coolant Temperature Sensor Circuit:





OPERATION

As engine temperature increases, sensor resistance decreases. The ECU monitors engine temperature by the sensor output Voltage and provides optimum fuel enrichment when the engine is cold.

CONSTRUCTION

The Coolant Temperature Sensor is a thermistor type sensor.