Q: How to replace the Engine Coolant Temperature (ECT) sensor on Chevrolet Trailblazer?
A: A thermistor, the Engine Coolant Temperature (ECT) sensor is a resistor that varies its resistance value in relation to temperature. The voltage signal coming from the sensor to the PCM is directly affected by this change in resistance values. When the temperature of the sensor rises, their resistance value goes down and vice versa. The first step to replacing it involves draining out the cooling system completely. After that, pull apart the electrical connector from the sensor harness. Alternately, on six-cylinder engines, disconnecting and removing alternator and remove it easily and carefully. Unscrew the sensor from its position on the engine gently. However, with six-cylinder engines, it is threaded into an engine block. On v8 engines, just above Number One spark plug on front side of left cylinder head is sited ECT Sensor. If there isn't any sealing compound applied on threads of a new sensor cover them using Teflon sealing tape so as to avoid leaks occurring during installation process. Finally one does installation after removing.
Q: What is the purpose of the Coolant Temperature Sensor for Chevrolet Trailblazer?
A: The coolant temperature indicator system includes a gauge or warning light on the dashboard and a sensor on the engine. The sensor serves multiple purposes, acting as an information sensor for the fuel and emissions systems and as a sending unit for the temperature gauge. If overheating, check the coolant level and make sure the wiring and fuses are intact. If the sensor is functioning properly, have the temperature gauge checked using a scan tool to access information from the PCM.