SL L4-1.9L SOHC VIN 9 (1991)
Coolant Temperature Sensor/Switch (For Computer): Description and Operation
Coolant Temperature Sensor.
Coolant Temperature Sensor (CTS) Wiring.
DESCRIPTION
The coolant temperature sensor is identical to the air temperature sensor. it is mounted in a coolant passage located in the cylinder head. The signal
received by the PCM indicates the temperature of the engine coolant, which is an indication of engine operating temperature. This sensor input is
used by the PCM for fuel enrichment, ignition timing, EGR operation, canister purge control, idle speed control, and Closed Loop fuel control.
