EuroV MBE 900 Operators Manual 13 Diesel Exhaust Fluid Level Warning Lamps 13.1 Diesel Exhaust Fluid Level Warning Lamps A four light bar segment indicates the Diesel Exhaust Fluid (DEF) level in 25% increments. Low DEF levels will trigger a decrease in the engine's performance. The use of improper DEF fluid will trigger a decrease in the engine's performance. In an empty or an ignored state and the diesel fuel tank is filled without filling the DEF tank, the vehicle's speed will be limited to 5 mph until DEF is detected in the DEF tank. Figure 1. Driver Card All information subject to change without notice. 27 DDC-SVC-MAN-0207 Copyright © 2019 DETROIT DIESEL CORPORATION