Chevrolet Low Cab Forward 2016 Manual page 194

Incorrect DEF/SCR System Malfunction (Type A) Warnings
Stage Stage 1
DIC main display
DEF gauge (DIC sub
Various
display 2)
Indicator light(s)
Stage 2 Stage 3
Various Various
Slow blinking Fast blinking
Driving and Operating
Stage 4
Various
Fast blinking
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