Mercedes-Benz OM 471 Introduction Into Service Manual page 214

GF49.10>W>3008H
ENGINES 471.9 in MODEL 963, 964 with CODE (M5Z) Engine version Euro VI
Location
2 Ammonia blocking catalytic
converter
3 SCR catalytic converter
A57 Exhaust aftertreatment unit outlet
NOx sensor control unit
A57 b1 Exhaust aftertreatment unit outlet
NOx sensor
A67 AdBlue" metering device
A70 Exhaust aftertreatment unit inlet
NOx sensor control unit
B38 Exhaust pressure sensor
downstream of diesel particulate
filter
B70 Exhaust temperature sensor
downstream of diesel particulate
filter
B73 Exhaust temperature sensor
downstream of SCR catalytic
converter
The SCR catalytic converter (3) is in the exhaust aftertreatment
unit, and forms a single unit together with the ammonia blocking
catalytic converter (2).
Task
The SCR catalytic converter (6) reduces the toxic nitrous oxides
(NOx) generated by fuel combustion into non>toxic nitrogen (N
and water (H O).The ammonia blocking catalytic converter (2) is
2
primarily used to convert non>reactive ammonia particles (NH
which would otherwise be easily perceptible in the vehicle
environment because of the low odor threshold of ammonia.
i Introduction of engine OM 471 and exhaust aftertreatment > 09/2011 >
Component description for SCR catalytic converter
),
3
– This printout will not be recorded by the update service. Status: 09 / 2011 –
Design
The SCR catalytic converter (3) and the ammonia blocking catalytic
) converter (2) consist of two cylindrical catalytic converter
2
elements in a metal sleeve that are connected in series. In order to
make the chemical reactions take place, this ceramic block has a
special coating made from a series of rare metals such as titanium,
tungsten, platinum and vanadium.
System components
20.7.11
W14.40>1575>76
211