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Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-13336155) - 2020 - CRC - 5/6/19
30
Driving and Operating
The speed limitation will occur in a
series of steps with the final speed
limitation being 8 km/h (5 mph)
along with a flashing warning light
and chimes.
Adding fresh DEF to the system
may resolve the problem after
several kilometers/miles of driving,
depending on several factors. If the
DIC message persists, see your
dealer or additional DIC messages
may display.
Service DEF System
If a problem occurs with the DEF
system, a DIC message displays
along with distance until vehicle
speed is limited.
The speed limitation will occur in a
series of steps with the final speed
limitation being 8 km/h (5 mph)
along with a flashing warning light
and chimes.
In some cases, this message will
clear itself, indicating that the DEF
system was able to correct the
condition. If the DIC message
persists, see your dealer or
additional DIC messages may
display.
Service Emission System
If a problem occurs with the vehicle
emission system, a DIC message
displays along with distance until
vehicle speed is limited. The speed
limitation will occur in a series of
steps with the final speed limitation
of 88 km/h (55 mph) and chimes. In
some cases, this message will clear
itself, indicating that the emission
system was able to correct the
condition. If the DIC message
persists, see your dealer or
additional DIC messages may
display.
Brakes
Exhaust Brake
The exhaust brake can be used to
enhance the vehicle brake system
and reduce brake lining wear.
Downshifts may be automatically
selected to increase engine speed,
which increases the effectiveness of
the exhaust brake. The number of
downshifts selected is determined
by the length of time the brakes are
applied and the rate the vehicle is
slowing. The system delivers the
correct amount of braking to assist
in vehicle control. The heavier the
vehicle load, the more active the
engine exhaust brake will be. Use of
the exhaust brake will help maintain
vehicle speed when used with
cruise control. See
“
Cruise Control
”
in the owner
’
s manual.
Automatic downshifts will not occur
if the vehicle is in Range Selection
Mode. See
“
Manual Mode
”
in the
owner
’
s manual.