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

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

This sensor's input value is used to calculate fuel delivery and ignition timing. The sensor is mounted on the thermostat housing and samples engine coolant temperature by means of a NTC semiconductor resistor.