MTU 4R 1000 SERIES, Operating Instructions Manual

Page: 70 / 88

before bleeding. Drain fuel prefilter on chas-
sis frame
:
regularly.
Draining the fuel prefilter on the chassis
frame
X
Place a collector under drain plug
;
.
X
Turn drain plug
;
open.
X
Press manual fuel pump
?
and collect the
fuel/water mixture.
X
Turn drain plug
;
closed.
Bleeding using the manual fuel pump of
the fuel prefilter on the chassis frame
X
Unscrew the fuel tank filler cap.
X
Place the collector underneath fuel prefil-
ter
:
.
X
Unscrew bleed screw
A
.
X
Press manual fuel pump
?
repeatedly until
the fuel escaping at bleed screw
A
is free
of bubbles.
X
Tighten bleed screw
A
.
i
If there was no fuel in the fuel tank, press
manual fuel pump
?
again until there is
noticeable resistance.
i
Then bleed the fuel circuit on the engine
as described under "Bleeding the fuel sys-
tem without a fuel prefilter on the chassis
frame".
X
Tighten the fuel tank filler cap.
X
Turn the key to the start position in the
ignition lock and hold it. Do not depress the
accelerator pedal whilst doing so.
i
The starting procedure is automatically
cancelled after approximately 60 seconds.
X
Repeat the starting procedure after a wait-
ing period of approximately 1 minute.
X
If the engine starts normally, depress the
accelerator pedal several times. The fuel
system is completely bled.
Electrical fuses
Important safety notes
G
WARNING
If you manipulate, bridge or replace a faulty
fuse with a fuse of a higher amperage, the
electric cables could be overloaded. This may
result in a fire. There is a risk of an accident
and injury.
Always replace faulty fuses with specified new
fuses of the correct amperage.
The individual electrical circuits are protected
by safety fuses or automatic circuit-breakers.
Blown fuses or defective automatic circuit-
breakers must be replaced by equivalent
fuses with the fuse ratings recommended in
the fuse allocation chart. Fuses with the same
fuse rating are the same colour.
Further information is available from any MTU
or MTU-authorised Mercedes-Benz Service
Centre (
Y
page 9).
The vehicle-specific fuse allocation chart is
provided by the vehicle manufacturer.
If the newly inserted fuse also blows, have the
cause traced and rectified at a qualified spe-
cialist workshop, e.g. a Mercedes-Benz Ser-
vice Centre.
X
If a circuit fails, switch off the consumer
equipment and switch the ignition lock to
position
0.
Checking and replacing a safety fuse
X
Pull the fuse out of the module using the
pliers and carry out a visual inspection.
X
If the fuse wire has melted, replace the
blown fuse with a spare fuse.
X
Switch on consumers and check that they
function correctly.
If the safety fuse burns out again, have the
electrical system checked at a qualified spe-
cialist workshop.
68
Electrical fuses
Troubleshooting