freightliner S2 Operator's Manual page 65

Exhaust Aftertreatment Systems
7. The regen cycle will finish after 20 to 60 minutes,
at which time engine idle speed will drop to nor-
mal and the vehicle can be driven normally. The
HEST lamp may be illuminated, but will go out
when the vehicle speed exceeds 5 mph (8 km/h),
or the system has cooled to normal operating
temperature. See Fig.
shut off.
8.
To stop a parked regen at any time during the
process, engage the clutch, service brake, or
accelerator pedal, or turn off the engine.
DPF Maintenance
Eventually ash will accumulate in the DPF and the
filter will require servicing. DPF servicing must be
performed by an authorized technician, following the
engine manufacturer's instructions. A record must be
maintained for warranty purposes, that includes:
•
date of cleaning or replacement;
•
vehicle mileage;
•
particulate filter part number and serial number.
Diesel Exhaust Fluid and Tank,
EPA10 and Newer Engines
Diesel Exhaust Fluid
Diesel exhaust fluid (DEF) is used in the ATS to
lower NOx in the exhaust stream. DEF is colorless
and close to odorless (it may have a slightly pungent
odor similar to ammonia). It is nontoxic, nonflam-
mable, and biodegradable. It is mildly corrosive to
aluminum, but does not affect the strength or struc-
ture of the aluminum.
White crystals may be noticeable around compo-
nents that come into contact with DEF. The crystals
are easily removed with water.
DEF consumption varies depending on ambient con-
ditions and vehicle application.
Freezing Conditions
DEF freezes to slush at around 12°F (-11°C). It is not
damaged or destroyed if frozen, and is fully usable
when thawed. The DEF in the tank is allowed to
freeze while a vehicle is non-operational. At start-up,
normal operation of the vehicle is not inhibited if the
DEF is frozen; an immersion heater with engine cool-
9.5
9.2. The DPF lamp will
ant flowing through it warms the DEF once the en-
gine is running, allowing the SCR system to operate.
Pre-2013 DEF supply lines are electrically-heated
and are purged when the engine is shut down; com-
plete purging of the DEF lines requires approximately
five minutes after the engine is shut down.
DEF supply lines with engine model year 2013 and
newer are designed to survive freezing conditions
while containing DEF, so purging is not required.
DEF Tank
Engines that are compliant with EPA10 and newer
regulations are equipped with a DEF tank located
between the ATS and the fuel tank, or an optional
location forward of the fuel tank. The DEF tank has a
19 mm filler neck inlet that prevents the hose from a
diesel outlet from being inserted, and has a blue cap
for easy identification.
The DEF tank will require filling a minimum of ap-
proximately every second diesel refuel depending on
the DEF tank capacity. The S2 Chassis has an 11.5-
gallon tank capacity. DEF consumption is approxi-
mately 2% of fuel consumption, dependent on ve-
hicle operation. For every 50 gallons of diesel fuel
consumed, approximately 1 gallon of DEF will be
consumed.
Fuel/DEF Gauge
The fuel and DEF levels are measured in a dual pur-
pose fuel/DEF gauge. See
Fuel level is indicated at the top of the gauge. Below
the fuel level, a low fuel warning lamp illuminates
amber when the fuel level drops below 1/8th of the
capacity.
The lower portion of the gauge has a DEF warning
lamp that illuminates when the DEF tank is near
empty, and a DEF lightbar that indicates the level in
the DEF tank as follows.
•
Four bars illuminated green—Between 75%
and 100% full
•
Three bars illuminated green—Between 50%
and 75% full
•
Two bars illuminated green—Between 25%
and 50% full
•
One bar illuminated green—Between approxi-
mately 10% and 25% full
Fig. 9.7.