IC Bus CE Series 2020, Operation And Maintenance Manual

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Operation
CAUTION
To prevent property damage, IC Bus requires the
use of Diesel Exhaust Fluid (DEF) that meets or
exceeds ISO-22241-1.
There is no acceptable
substitute.
IC Bus recommends using Fleetrite ® brand Diesel Exhaust Fluid.
DEF Tank
The DEF tank filling inlet is located on the right-side of the
vehicle, near the fuel tank door and behind a fill door labelled
DEF Fluid. For reference, see Figure Exterior Components in
section
Model Description > Exterior Components .
The filler neck inlet on a DEF tank has a BLUE cap and has a
smaller diameter (19 mm) than that of a filler neck on the diesel
fuel tank.
The SCR system is designed to operate normally also under
freezing conditions while containing DEF. Though DEF freezes
at approximately 10°F (-12°C), no operator interaction is
necessary when operating in cold temperatures.
Under cold or very dry conditions, water vapor can be seen
coming from the vehicle tailpipe.
This is normal system
operation. The water vapor will disappear within a few minutes
of normal vehicle operation.
After the key is turned OFF on a vehicle with SCR system, a
pumping sound may be heard from underneath the vehicle. The
sound is made by the aftertreatment DEF dosing unit while it
purges any unused DEF from the system and returns it to the
DEF tank. This is normal system operation. It takes about 70
seconds to complete.
CAUTION
To prevent vehicle / property damage, after
turning the key OFF on a vehicle with Selective
Catalyst
Reduction (SCR) system, do not
disconnect the vehicle batteries while you
can hear a pumping sound from underneath
the vehicle.
The sound may last for about 60
seconds.
Low DEF Level
WARNING
To prevent personal injury and / or death, or
damage to property, maintain the adequate Diesel
Exhaust Fluid (DEF) level to avoid a loss of
engine power and vehicle speed.
On the instrument panel, you can monitor the fluid level using the
DEF Level Gauge. You will see additional warnings if the DEF
is too low. If DEF level decreases to 2.2% or lower, the engine
performance will start to be de-rated by at least 25%. If the DEF
level remains 0% for an extended time, the vehicle speed will
be limited to 5 mph (8 km/h). Refill the DEF tank with approved
DEF at any point, and the vehicle will resume normal operation.
See the following table for a detailed explanation of indicators
about low DEF level.
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