Komatsu PW118MR-11, Operation & Maintenance Manual

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2.
from the standard screen, press the F6 key to display: “Af-
tertreatment Devices Regeneration”
If this screen does not show, push F1 and F2 to toggle to
this screen.
3.
Select Yes to cancel regeneration disable and push F6.
ABOUT THE OPERATION OF UREA SCR SYSTEM
The Urea SCR System automatically starts operating as soon as the engine is started.
Even after the engine starting switch is turned to the OFF position, the devices will still be in operation for sever-
al minutes to purge any DEF in the lines, the injector and the supply pump back to the DEF tank. It does not
indicate any abnormality. When DEF has been returned to the tank, the devices stop.
Do not turn OFF the battery disconnect switch while the devices are still in operation. When the devices com-
plete their shutdown process, the system operating lamp will go out, and the battery disconnect switch may be
disconnected.
ABOUT THE OPERATION IN COLD WEATHER
The DEF freezes at -11 °C.
Urea SCR system is equipped with a heating system to thaw frozen DEF once it is frozen, for example, during
parking and to prevent DEF from freezing during operation.
In case DEF freezes during parking, once the engine starts running the heating system automatically starts pro-
viding heat to thaw frozen DEF. The pump and the injector start working only after a proper amount of DEF is
thawed. This may be noticed as a delay in the start of functioning of the pump and the injector.
The heating system is also activated automatically during operation to prevent DEF from freezing whenever the
ambient temperature drops below a certain threshold where DEF in the system may freeze. In the event that the
ambient temperature drops further than a temperature where the heating system is capable of maintaining fluidi-
ty of DEF, the DEF system automatically starts purging the remaining DEF back to the tank and stops pumping
and injection while heating continues. Once the ambient temperature rises above a temperature where DEF
system becomes functional, it resumes operation automatically.
Short duration of white plume given off from the tail pipe may be visible at and shortly after engine start-up in
cold weather, but this is not malfunction.
INDUCEMENT STRATEGY WHEN THE DEF TANK LEVEL BECOMES LOW
When the amount of DEF in the tank goes low, the Inducement strategy will be activated.
If Inducement starts, add DEF to the DEF tank immediately.
The DEF level caution lamp (1) on the monitor lights up, the audible alert starts, and the action level is dis-
played, and Inducement strategy is activated. Inducement strategy includes engine output deration, speed limi-
tation, or other warning actions intend to prompt the operator to maintain or repair SCR system.
RKA63330
EXPLANATION OF COMPONENTS OPERATION
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