Emissions Reduction Components

Exhaust Aftertreatment System, Optional

IMPORTANT: Depending upon local jurisdictional emissions guidelines, the vehicle may not be equipped with an emissions aftertreatment system (ATS). Adequate maintenance of the engine and the diesel particulate filter (DPF) are the responsibility of the owner/operator, and are essential to keep the emission levels low. Good operating practices, regular maintenance, and correct adjustments are factors that will help keep emissions within the regulations.

NOTICE

It is extremely important that the following guidelines be followed for engines that are equipped with an ATS, or damage may occur to the aftertreatment device, and the warranty may be compromised.

Use ultralow-sulfur diesel with 15 ppm sulfur content or less.

Do not use fuel blended with used engine lube oil or kerosene.

Use only engine lube oil with a sulfated ash level less than 1.0 wt%.

IMPORTANT: See the engine manufacturer's operation manual for complete details and operation of the ATS.

The ATS varies according to engine manufacturer and vehicle configuration, but the exhaust muffler is replaced by an aftertreatment device (ATD). Inside the ATD, the exhaust first passes over the diesel oxidation catalyst (DOC), then passes through the diesel particulate filter (DPF), which traps soot particles. The soot is reduced to ash during a process called regeneration (regen).

Regeneration

The harder an engine works, the better it disposes of soot. If the exhaust temperature is high enough, a process called passive regeneration (regen) occurs as the vehicle is driven normally. However, if the engine isn't running hot enough, the electronic controls may initiate an active regen , whereby extra fuel is injected into the exhaust stream to elevate filter temperatures and reduce the soot trapped in the DPF to ash. Active regen happens only when the vehicle is moving above a certain speed, determined by the engine manufacturer. See your engine operation manual for complete details. Both active and passive regen happen automatically, without driver input.

Active regeneration can occur automatically anytime the vehicle is moving. The exhaust gas temperature could reach 1500°F (800°C), which is hot enough to cause a fire, heat damage to objects or materials, or personal injury to persons near the exhaust outlet. The exhaust temperature can remain high even after the vehicle has stopped. When stopping the vehicle shortly after an automatic regen, ensure the exhaust outlets are directed away from structures, vegetation, flammable materials, and anything else that may be harmed by exposure to high heat.

See Regen Switches , below, for instructions on preventing automatic regen if necessary.

When operating conditions do not allow for ATD filter cleaning by active or passive regen, the vehicle may require a driver-activated parked regen . When this occurs, the DPF lamp illuminates, indicating that a regen is required. The driver must either bring the vehicle up to highway speed to increase the load (thus starting an active regen), or park the vehicle and initiate a parked regen. See Regen Switches , below, for instructions on initiating a parked regen.

Regen Switches

The regen request switch, located on the dash, is used to initiate a parked regen. See Fig. 11.1 .

Some vehicles may be equipped with a regen request/inhibit switch. See Fig. 11.1 . To stop a regen in progress or prevent the start of a regen, press the lower half of the switch. Regen will be delayed until the switch is no longer active.

NOTE: The regen switch can initiate a parked regen only when the DPF lamp is illuminated.

1. Regen Request Switch
2. Regen Request/Inhibit Switch

Fig. 11.1, ATS Regen Switches

During parked regen, exhaust temperatures are very high and could cause a fire, heat damage to objects or materials, or personal injury to persons near the exhaust outlet.

Before initiating a parked regeneration, make certain the exhaust outlets are directed away from structures, vegetation, flammable materials, and anything else that may be harmed by prolonged exposure to high heat.

To initiate a parked regen, perform the following steps.

Park the vehicle away from all flammable materials, put the transmission in neutral, and set the parking brake.

Start and warm the engine until the coolant temperature is at least 150°F (66°C).

Press and hold the regen request switch for five seconds. As the regen process is initiated, engine rpm increases and the HEST lamp illuminates to indicate extremely high exhaust temperatures.

IMPORTANT: The driver is responsible forensuring,during the entire regen cycle, that anything that could be harmed by exposure to high heat does not come in contact with theexhaustgases flowing from the outlets.

The regen cycle will finish after 20 to 60 minutes, at which time engine idle speed drops to normal and the vehicle can be driven normally. The HEST lamp is extinguished when vehicle speed exceeds 5 mph (8 km/h) or the system has cooled to normal operating temperature.

To stop a parked regen at any time during the process:

depress the clutch pedal or accelerator pedal;

take the parking brake off;

press and hold the regen inhibit switch until idle returns to normal;

shut down the engine.

ATS Warning Lamps

There are three warning lamps that alert the driver of high exhaust temperature, the need to perform a parked regen or service the DPF, or of an engine fault that affects emissions.

See Fig. 11.2 for an explanation of the ATS warnings, and actions required to avoid engine protection sequences.

Malfunction Indicator Lamp (MIL)

A steadily illuminated yellow malfunction indicator lamp (MIL) indicates an engine fault that affects emissions. See Fig. 11.3 .

DPF Status Lamp

When soot accumulates in the DPF and the DPF status lamp illuminates, see Fig. 11.4 , perform a parked regen or bring the vehicle up to highway speed to increase the load (thus starting an active regen).

Fig. 11.2, ATS Warning Lamps

Fig. 11.3, Malfunction Indicator Lamp (MIL)

Fig. 11.4, DPF Status Lamp

If the DPF status lamp blinks while the CHECK engine lamp is illuminated, initiate a parked regen immediately in order to prevent an engine derate.

If the red STOP engine lamp illuminates with the blinking DPF lamp and the CHECK engine lamp, begin a parked regen in order to prevent an engine shutdown. Park the vehicle and perform a parked regen.

High Exhaust System Temperature (HEST) Lamp

Slow (10-second) flashing of the high exhaust system temperature (HEST) lamp indicates that a parked regen is in progress, and the engine's high idle speed is being controlled by the engine software, not the vehicle driver.

Steady illumination of the HEST lamp alerts the driver of high exhaust temperature during the regen process if the vehicle speed is below 5 mph (8 km/h), or during a parked regen. See Fig. 11.5 .

Fig. 11.5, HEST Lamp

Maintenance

Authorized service facilities must perform any DPF service. For warranty purposes, maintain a record that includes:

date of cleaning or replacement;

vehicle mileage;

particulate filter part number and serial number.