Sending Unit And Sensor, Fuel Level: Operation: Operation: Fwd

WARNING: This page is about a different car, the 2014 Dodge Journey. However, it is still accessible from the selected car via links, so may be relevant.

Front Wheel Drive (FWD) vehicles have a single fuel level sending unit and sensor located on the fuel pump module reservoir. As the fuel level float is moved, the sending unit resistance changes in consistent incremental steps from low resistance (float up) to high resistance (float low). The Powertrain Control Module (PCM) provides a 5 volt reference and a ground to the fuel level sensor. The PCM monitors the fuel level sensor voltage for a specific change based upon a calculated value and the vehicle operating conditions.

The fuel level sending unit and sensor circuits are continuously monitored by the PCM. If the PCM detects a problem in any monitored circuit, it will store a Diagnostic Trouble Code (DTC) in its memory circuits. Such a DTC can be retrieved from the PCM through the Controller Area Network (CAN) data bus using a diagnostic scan tool connected to the Data Link Connector (DLC).

The hard wired circuits between the fuel level sending unit and sensor and the PCM may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. However, conventional diagnostic methods will not prove conclusive in the diagnosis of the fuel level sending unit and sensor or the electronic controls or communication between other modules and devices that provide some features of the fuel injection system. The most reliable, efficient, and accurate means to diagnose the fuel level sending unit and sensor or the electronic controls and communication related to fuel injection system operation requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.