Eclipse L4-1997cc 2.0L DOHC (1991)
Coolant Temperature Sensor / Switch HVAC: Description and Operation
Coolant Temperature Switch Circuit (A/C Only)
The Coolant Temperature Switch, located in the thermostat housing, is a contact type switch. It is normally in the closed position allowing current flow.
When the engine coolant temperature is 233 - 244° F (112 - 118° C) the switch will open cutting power to the ECU, and helping to prevent engine
overheating.
