Engine Coolant Temperature (ECT) Sensor

On Trionic T-5 systems, ECT is located in intake manifold between cylinders No. 3 and 4. On Trionic T-7 systems, ECT is located on left side of cylinder head. Sensor transmits an engine temperature signal to ECM. If ECM fails to receive this signal, it defaults to a substitute temperature value equal to intake air temperature on startup. It then increases that value by 1.8°F (1°C) for every 150 revolutions of the crankshaft until a value equal to 194° (90°C) is reached.