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

PURPOSE
The coolant temperature switch is a dual function unit that is controlled by engine coolant temperature and is integral with the intake manifold (EFE) heater control switch. When closed, the switch indicates that the engine is cold (coolant temperature below 135°F).