Bluetec ® Exhaust Gas Aftertreatment; Exhaust Gas Recirculation; Warning And Indicator Lamps - Mercedes-Benz OM 470 Euro VI Operating Instructions Manual

Exhaust gas aftertreatment control
unit (ACM)
The exhaust gas aftertreatment control module
(ACM) is secured to the exhaust gas aftertreat-
ment unit with a bracket or is secured to the
vehicle in a protected location. It regulates and
controls the exhaust gas aftertreatment system.
Functions of the exhaust gas aftertreatment
control module (ACM):
Evaluation of sensor signals
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The sensor signals of the directly connected
sensors are evaluated. Data provided via the
CAN by the engine management control mod-
ule (MCM) and the control units for the NOx
sensors is also evaluated.
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AdBlue /DEF injection
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Calculation of the required amount of
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AdBlue /DEF and supply of AdBlue
actuation of the SCR delivery pump.
Injection by actuation of the AdBlue
metering unit.
Monitoring and control of the regeneration of
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the diesel particle filter (DPF)
The diesel particle filter (DPF) is subject to per-
manent monitoring of the load. If necessary,
active regeneration is initiated.
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BlueTec exhaust gas aftertreatment
The exhaust gas aftertreatment system is acti-
vated immediately after the engine is started
and remains activated during engine operation.
It ensures that the pollutant emissions in the
exhaust gas are reduced to the limits stipulated
in the emissions standard.
Exhaust gas treatment is carried out by:
selective catalytic reduction (SCR) with
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ammonia slip catalytic converter
diesel oxidation catalytic converter (DOC)
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the diesel particle filter (DPF)
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In order to ensure correct operation of the
exhaust gas aftertreatment system, only oper-
ate the engine/vehicle with the AdBlue
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ing agent. AdBlue /DEF is not refilled as part of
the maintenance work. You should therefore top
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up the AdBlue /DEF tank regularly.
Operating the vehicle without AdBlue
another medium that has not been approved by

Warning and indicator lamps

Daimler invalidates the engine's operation cer-
tification/approval.

Exhaust gas recirculation

Exhaust gas recirculation (EGR) serves primarily
to reduce the amount of nitrogen oxide prior to
exhaust gas aftertreatment. This serves to com-
ply with emissions limits.
Exhaust gas is added to the fresh air being
drawn in or charged so that the concentration of
oxygen in the combustion mixture is reduced.
Combustion deteriorates if the concentration of
exhaust gas in the combustion mixture is too
high.
The emission of soot particles, carbon monoxide
(CO) and hydrocarbons (HC) increases.
Conversely, the emission of nitrogen oxides
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/DEF by
(NOx) would increase if the concentration of
fresh or charged air were too high.
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/DEF
Warning and indicator lamps
Important safety notes
If you ignore warning and indicator lamps, you
will not be able to recognise failures and mal-
functions in components or systems. Driving/
braking characteristics may be different and the
operating and road safety of your vehicle may be
limited. Have the affected system checked and
repaired at a qualified specialist workshop.
Always observe the warning and indicator lamps
and follow the corresponding corrective actions
( page 27).
Y
Overview
The display format for indicator and warning
lights is vehicle-specific. When doing so, also
observe the notes in the vehicle operating
instructions. The symbols listed below are
examples and may differ from those symbols
displayed in the vehicle.
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reduc- In the event of a fault or warning, a warning lamp
or indicator lamp lights up automatically.
Depending on the priority of the fault or warning,
the warning and indicator lamps light up in dif-
ferent combinations.
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or with
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