Engine coolant temperature is required primarily for fuel enrichment during cold starting and during the warm-up period that follows. This sensor should always be mounted on the engine side of the thermostat.
G4X ECUs can measure the temperature using a thermistor (NTC or PTC) sensor or a sensor with a 0-5V output. Any sensor calibration is permitted.
Thermistor sensors have a resistance that changes with temperature and are commonly used in automotive applications. When wiring thermistor sensors the polarity is NOT important. An Analog Temp wire should be connected to one terminal on the sensor while the other terminal must be connected to the Sensor Ground (green) wire.
When using a sensor that produces a 0-5V output or in piggy back application where a factory ECU is already providing the temperature sensor pull-up resister, connect the ECT signal to an Analog Volt channel.
G4X ECUs are compatible with any NTC or PTC thermistor sensor. The recommended sensor is a Bosch 0 280 130 026 sensor. A number of pre-calibrated sensor options are also provided in PCLink Tuning Software. Note that most factory sensors will use the Standard Bosch NTC calibration. In order to use a sensor with a different calibration you will need to know how the sensor’s resistance changes with temperature and enter this information into the ECU via PCLink Tuning Software.