Theory Of Operation
WARNING: This page is about a different car, the 2015 RAM 1500. However, it is still accessible from the selected car via links, so may be relevant.
The Fuel Temperature Sensor is combined with the Fuel Heater and located on the Fuel Filter/water separator housing which is mounted on the left frame rail next to the Transmission. The Fuel Temperature Sensor operates as a typical two wire sensor. It receives a 5-Volt signal on the (K156) Fuel Temperature Sensor Signal circuit and uses the (K159) Sensor Ground circuit.