Def Gauge

WARNING: This page is about a different car, the 2017 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.

A Diesel Exhaust Fluid (DEF) level gauge displays the actual level of DEF in the DEF tank. DEF is required to maintain normal vehicle operation and emissions compliance. This gauge consists of a movable gauge needle or pointer controlled by the instrument cluster circuitry and a fixed 90 degree scale on the cluster overlay that reads left-to-right from E (or Empty) to F (or Full).

The fuel gauge graphics are white against a black field except for a single red graduation at the low end of the gauge scale making them clearly visible within the instrument cluster in daylight. When illuminated from behind by the panel lamps dimmer controlled cluster general illumination lighting with the exterior lamps turned ON. The gauge needle has internal optical illumination. Gauge illumination is provided by an Light Emitting Diode (LED) located on the instrument cluster electronic circuit board.