Pony Pickup (Canada) L4-1238cc 1.2L SOHC (1986)
Electronic Control Unit: Technical Service Bulletins
Engine Coolant Temperature Sensor - Diagnosis
Group: ENGINE ELECTRICAL
Date: AUGUST, 1998
ENGINE COOLANT TEMPERATURE SENSOR DIAGNOSIS
The engine coolant temperature sensor is located in the coolant passage of the cylinder head. It detects engine coolant temperature and sends signals to
the powertrain control module (PCM). The engine coolant temperature sensor uses a thermistor which is sensitive to changes in temperature. The electric
resistance of a thermistor decreases in response to a rise in temperature. Thus, when the temperature increases, the output voltage decreases The PCM
determines engine coolant temperature by the sensor output voltage and provides optimum fuel enrichment when the engine is cold.
This bulletin provides diagnosis and repair procedures for engine coolant temperature sensors.