Engine help

2015 Freightliner Cascadia check engine light came on and stays on after water pump was replaced. After 15-30 mins of driving red stop engine and another orange light comes on and then goes off after about 5 mins but the first orange check engine light remains on

 

It’s not giving any, its indicating no active codes

 

Just popped up!!!!
Active 1
EEC
DEF tank empty 25% derate (i know I need fuel but not sure I it means more)
Diagnostic code SPN 1761 FMI 31

 

DEF all green, tank full and orange engine light still on only change is the other 2 (check and stop) has not cycle back on at all

 

It worked, thank you!!!!!