MTU 4R 1000 SERIES, Operating Instructions Manual

Page: 39 / 88

Each malfunction is stored in the system with
its own fault code. Temporary faults are also
stored.
Fault codes can be read by a qualified spe-
cialist workshop using a diagnostic tester
(
Y
page 7).
Oil pressure
If the
1
indicator lamp does not go out or
if it lights up when the engine is running,
switch off the engine. Searching for and elim-
inating the cause of the malfunction
(
Y
page 71).
Operating restrictions
The electronic engine management system
monitors:
R
emissions-relevant malfunctions in the
exhaust gas aftertreatment
R
malfunctions in the electronic monitoring
of the exhaust gas aftertreatment system
R
consumption, level and quality of the
AdBlue
®
/DEF reducing agent
R
the efficiency of the catalytic converter in
accordance with the permitted thresholds
for nitric oxide emissions (NOx)
Operating restrictions in the form of torque
reduction and thus output and speed limita-
tion may occur.
Emergency switch for overriding
operating restrictions
If an emissions-relevant malfunction in the
exhaust gas aftertreatment or the
AdBlue
®
/DEF supply is detected, this can
cause an operating restriction (limitation of
engine torque and engine speed).
In case of emergency a push-button switch
can be operated to override the operating
restriction. This means that full engine power
is available for a maximum of 30 minutes. This
emergency function by operating the switch
can be activated a maximum of three times.
When the final operating restriction (idling
speed and 20% of torque) has been reached,
the push-button switch is deactivated.
Displays
Rev counter
!
If you exceed the maximum permissible
engine speed, the warning tone sounds.
You should not drive and change gear by
the sound of the engine, but according to
the engine speed shown in the rev counter.
Avoid driving in the red overrevving range.
This could lead to engine damage.
The engine speed display is the responsibility
of the vehicle manufacturer and is not nec-
essarily supplied by Mercedes-Benz. Daimler
AG recommends that the vehicle manufac-
turer uses a rev counter divided by:
R
operational efficiency
R
engine braking range
R
engine overrevving range
General notes on the rev counter:
R
Keep an eye on the rev counter while driv-
ing and stay within the economical operat-
ing range.
In some situations it may make sense to
operate the engine outside the economical
engine speed range, e.g. on uphill gradients
or when overtaking.
R
If you run the engine within the economical
engine speed range, you achieve low fuel
consumption and reduced wear.
R
In engine braking mode, drive in the middle
engine speed range. The highest engine
braking effect will be achieved just before
the red overrevving range.
R
When driving downhill, make sure that the
engine speed does not enter the overrev-
ving range (marked red).
Displays
37
Operation
Z