Chevrolet 4500HD Series 2019 Manual page 198

Stage
Solid
Indicator light(s)
Warning buzzer 1 short beep
Vehicle speed is
Restrictions limited to
89 km/h (55 MPH)
Refill DEF as soon
Required action
as possible *1
DEF Tank Level is Low/Empty (cont'd)
Stage 1 Stage 2
Slow blinking
3 short beeps *3
Vehicle speed is
limited to
56 km/h (35 MPH)
Refill DEF tank
immediately *1
Driving and Operating
Stage 3
Fast blinking Fast blinking
3 quick beeps *4 Continuous beeping
Vehicle speed is Vehicle speed is
limited to limited to
56 km/h (35 MPH) 8 km/h (5 MPH)
Refill DEF tank Refill DEF tank
immediately *1 immediately *1
197
Stage 4