Definition of node. 1a : a pathological swelling or enlargement (as of a rheumatic joint)b : a discrete mass of one kind of tissue enclosed in tissue of a different kind.
Diesel exhaust fluid (DEF) from a separate tank is injected into the exhaust pipeline, where the aqueous urea vaporizes and decomposes to form ammonia and carbon dioxide. Within the SCR catalyst, the NO. x are catalytically reduced by the ammonia (NH. 3) into water ( H2O) and nitrogen (N.
Diesel Exhaust Fluid (DEF) freezes into a crystalline slush at 12Â°F (-11Â°C) and should not be kept at temperatures above 86Â°F (30Â°C). If DEF is frozen on your vehicle, for example overnight or over a weekend, you do not need to take any action. Use the vehicle as you normally would.