freightliner S2 Operator's Manual page 62

Operating at reduced engine load will allow soot to
accumulate in the DPF. When this occurs, the DPF
lamp illuminates, indicating that a regen must be per-
formed, and the driver must either bring the vehicle
up to highway speed to increase the load, or park
the vehicle and initiate a parked regen. See Parked
Regen, later in this chapter for instructions.
NOTE: Beginning September 2, 2014 some
chassis are equipped with an option that allows
a regen to occur at 0 or 1 mph (0 or 2 km/h),
instead of the standard 5 mph (8 km/h) thresh-
old. Based on the engine programming param-
eter, if a regen occurs and vehicle speed is re-
duced to either 0 or 1 mph (0 or 2 km/h), the
regen process will not be cancelled.
If the vehicle is programmed for the 0 mph (0
km/h) parameter, vehicle speed can be reduced
to 0 mph (0 km/h) and the regen will continue.
Vehicles with this option are equipped with a
regen inhibit switch to cancel the regen if
needed.
If the vehicle is programmed for the 1 mph (2
km/h) parameter, vehicle speed can be reduced
to 1 mph (2 km/h) and the regen will continue. If
vehicle speed is less than 1 mph (2 km/h), the
regen will be cancelled.
After the exhaust stream passes through the ATD, it
flows through another canister housing the SCR de-
vice. A controlled quantity of DEF is injected into the
exhaust stream, where heat converts it to ammonia
(NH ) gas. This mixture flows through the SCR de-
3
vice, where the ammonia gas reacts with the NOx in
the exhaust, to produce harmless nitrogen (N
water vapor (H O), which then exits out of the tail-
2
pipe.
ATS Warning Lamps
Warning lamps in the driver's message center alert
the driver of situations with the ATS.
•
An illuminated DPF lamp indicates a regen is
needed. See Fig.
•
A slow, 10-second flashing of the HEST lamp
alerts the driver that a parked regen is in prog-
ress, but the exhaust temperatures are still
relatively cool. See
that the high-idle speed is being controlled by
the engine software, not the driver.
) and
2
9.1.
Fig. 9.2. It also indicates
Exhaust Aftertreatment Systems
09/25/2006
Fig. 9.1, Diesel Particulate Filter (DPF) Status Lamp
09/25/2006
Fig. 9.2, High Exhaust System Temperature (HEST)
•
A steadily illuminated HEST lamp alerts the
operator of high exhaust temperatures when
vehicle speed is below 5 mph (8 km/h) while it
is performing an automatic regen, and during a
parked regen. See
Parked Regen
During parked regeneration, exhaust tempera-
tures are very high, and could cause a fire, heat
damage to objects or materials, or personal in-
jury to persons near the exhaust outlet.
Before initiating a parked regeneration, make cer-
tain the exhaust outlets are directed away from
structures, trees, vegetation, flammable materi-
als, and anything else that may be damaged or
injured by prolonged exposure to high heat.
Lamp
Fig. 9.2.
DANGER
f610815a
f610816a
9.2