IC Bus CE Series 2020, Operation And Maintenance Manual

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Operation
NOTE: The ECM will not allow the Diamond Logic ® Engine
Brake to operate until the engine oil has reached the
acceptable minimum temperature, therefore, do not attempt
to activate the engine brake until the engine has reached
full operating temperature.
The optional Diamond Logic ® Exhaust Brake
accomplishes the braking effects using the closed
vanes of the turbocharger to increase exhaust
back-pressure and restrict airflow. The exhaust brake
is controlled by the ON / EXH BRAKE switch, located
in the switch panel. To turn the exhaust brake ON, place the ON
/ EXH BRAKE switch to the ON position (the switch indicator
will turn ON).
NOTE: Both the engine brake and exhaust brake features
will automatically deactivate if either the accelerator or the
clutch is pushed, or when the engine speed falls to 1,000
rpm.
Operational Modes
Coast Mode. In the coast mode, with the brake enabled, the
brake will activate when the driver hits the service brake (at or
above 1,200 rpm). The brake will deactivate if the driver releases
the brake pedal, or if the engine speed drops below 1,200 rpm.
Latched Mode. In the latched mode, with the brake enabled,
the braking will activate when the driver's foot is lifted from the
accelerator pedal (at or above 1,200 rpm). If the cruise ON / OFF
switch is in the ON position (with or without a cruise set speed),
the braking is activated by hitting the brake pedal. The braking
action will cease if the driver presses the accelerator, the clutch,
or if the engine speed drops below 1,200 rpm.
Cruise Mode. The cruise mode operates the same as the
latched mode, except that if the driver has the cruise turned ON,
the braking action helps to maintain the set speed. This feature
is especially valuable when going down a grade.
Exhaust Aftertreatment
Selective Catalytic Reduction System (If Equipped)
Introduction
Selective Catalytic Reduction (SCR) is the aftertreatment
technology that treats exhaust gas downstream of the engine.
It uses a urea-based Diesel Exhaust Fluid (DEF) and a catalyst
to significantly reduce nitrogen oxide (NOx) emissions.
Diesel Exhaust Fluid
Diesel Exhaust Fluid (DEF) is nontoxic, nonflammable, and
biodegradable. It is a carefully blended aqueous urea solution
of 32.5% high-purity urea and 67.5% deionized water.
If stored between 10° and 90°F (-12° and 32°C), DEF has shelf
life of 12 months minimum. For best shelf life, DEF containers
should be stored in a controlled environment out of direct
sunlight.
The amount of DEF consumption depends on engine speed and
load; therefore, it differs from vehicle to vehicle.
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