Circuit/System Description

The reductant level/temperature sensor is a solid-state device that provides the engine control module (ECM) with information on reductant level and temperature. The level/temperature sensor receives system voltage directly from the underhood electrical center and ground through a chassis ground circuit. The level sensor consists of three sensing elements. Reductant level sensor 3 is highest, reductant level sensor 2 is located between sensor 1 and 3. Reductant level sensor 1 is located at low reductant level. Reductant level sensor 3 is located at less than half range of the reductant tank level. The scan tool will display Active when the level sensors are in contact with reductant and Inactive when not in contact with reductant. An integrated temperature sensor monitors reductant temperature. Reductant level and temperature signals are processed within the sensor and supplied to the ECM as serial data messages. The ECM will set a DTC when it detects an invalid level or temperature serial data message from the sensor.