Chevrolet 4500HD Series 2019 Manual page 182

The selectable (switch) regeneration
required warning light (amber) will
turn on when regeneration cannot
be completed automatically. Perform
Running or Switch regeneration in
accordance with the proper
procedure. This is to restore DPF
function and is normal.
The exhaust pipe mixes air with the
exhaust gas to lower its temperature
before it leaves the exhaust pipe.
The frequency of regeneration
increases especially under the
following environments:
Midwinter.
Continuous low-speed driving for
long hours (The frequency of
regeneration increases
particularly with special
equipment vehicles such as
sweeper vehicles which mainly
travel at low speed. The
frequency of regeneration is
higher as compared to delivery
vehicles which mainly travel at
standard high speed).
Automatic regeneration is performed
under normal driving conditions
(DPF soot accumulation status level
5, and in rare cases, may be
performed at continuously
low-speeds for long hours, except
PM level 5); however, the
regeneration required warning light
(amber) may be displayed in the
DIC under the following driving
conditions:
When only low-speed driving at/
under vehicle speed of 15 km/h
(9 MPH) is performed.
When frequent engine start and
stop are performed.
When the engine stops every
time before the engine is
warmed up.
When continuous idling (over
1 hour) is frequently performed.
If the vehicle is stationary with the
engine idling during DPF
regeneration, the exhaust brake or
exhaust throttle operates. Operating
sounds will be heard when the
Driving and Operating
exhaust brake or exhaust throttle is
activated or deactivated. The
sounds do not indicate a fault.
White smoke could be emitted
briefly from the exhaust pipe in the
following situations, but it is not
indicating a fault.
Combustion of PM during DPF
regeneration.
During DPF regeneration of a
new vehicle which has been
driven a certain distance. The
vehicle may not emit white
smoke during its initial operation
when new.
Long continuous idling.
The exhaust brake may
automatically be activated in order
to prevent emission of white smoke
if the engine idles continuously over
an extended period of time.
White smoke may be produced
during switch regeneration; do not
perform switch regeneration in any
poorly ventilated indoor place.
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