Exhaust Restrictor (Engine
Warm-Up)
Exhaust Restrictor
If your vehicle has a Isuzu 6H Diesel Engine, it may
have a feature called an Exhaust Restrictor (NPE),
which uses an air actuated valve in the exhaust system
to restrict exhaust gas flow which enhances the
engine and heater warm-up.
Automatic Quick Warm-Up
If your vehicle has a DURAMAX®6600 engine, it has a
feature called an Automatic Quick Warm-Up, which
uses the turbocharger to restrict the exhaust gas flow
which enhances the engine and heater warm-up.
In both systems, exhaust restrictor or automatic quick
warm-up, the cold temperature high idle feature elevates
the engines idle speed, up to 1500 rpm, and restricts
the exhaust gas flow, when outside temperatures
are below 50°F (10°C), and the engine coolant
temperature is below certain levels. This feature
enhances heater performance by raising the engine
coolant temperature faster.For all engines this feature is already turned on. The
automatic quick warm-up on the DURAMAX
®engine
can be turned off and on by doing the following
procedure:
1. Turn the ignition to RUN, with the vehicle off.
2. Press the accelerator pedal to the floor and hold it
while quickly pressing and fully releasing the brake
pedal three times in less than eight seconds.
3. Release the accelerator pedal and start the engine.
The green exhaust brake/restrictor light below the
radio controls will be lit for 10 seconds.
If this feature is turned off, by doing the procedure
described previously, and then the engine is
started, the exhaust brake/restrictor light will flash
for 10 seconds and then it will turn off.
When the engine is started, it will slowly increase to the
high idle speed after a delay of a few seconds; up to
about two minutes. For this method to work properly
there must be no throttle or brake pedal faults, and the
throttle pedal must not fall below 75 percent of wide
open throttle while pressing the brake pedal.
2-22
The engine idle speed will return to normal once the
following conditions are met:
•Once engine coolant temperature reaches about
150°F (65°C).
•The intake temperature reaches a certain level.
The high idle speed will be temporarily interrupted and
the engine speed will return to normal if any of the
following conditions occur:
•The brake pedal is applied.
•The accelerator pedal is pressed.
•The automatic transmission is shifted out of
PARK (P) or NEUTRAL (N).
•The clutch pedal on the manual transmission is
pressed.
•Vehicle speed is detected.
Once these conditions no longer exist, the engine idle
speed will slowly increase to high idle after the
normal delay, if the conditions for engine coolant
temperature and air intake temperature are still met.
Engine Checks Before Operating
When you have started your engine, let it run for
20 to 30 seconds before you put a load on the
engine. But do not leave the vehicle while the engine
is running.
Avoid unnecessary idling of diesel engine equipped
vehicles.
If the engine idles too long, the temperature of the
engine coolant will fall below the normal operating
range. Low engine operating temperature causes
several conditions which affect engine operation and
reduce engine life.
The engine should be permitted to go through a
warm-up period. Operate the vehicle at a minimum of
600 rpm during the warm-up period. During this
period and during operation, the following observations
should be made.
2-23
For vehicles with Power Take-Off (PTO), monitor the
instrument panel cluster for lights related to the DPF.
All engines consume some amount of engine oil. This is
normal. The by-product of combustion of engine oil is
ash. The ash will become trapped in the DPF over
the life of the vehicle. Eventually, the buildup of ash will
restrict the exhaust gases and the DPF will need to
be cleaned or replaced.
SeeAccessories and Modifications on page 5-4for
important information.
Manual Regeneration Procedure
{CAUTION:
During DPF regeneration, the exhaust system
and exhaust gases are very hot. Stay clear of
the tailpipe area and do not park over things
that burn. You or others could be burned or
your vehicle could catch re. SeeParking Over
Things That Burn on page 2-44.If the yellow or red DPF indicator is on, you can clean
the DPF by performing a manual regeneration.
When it is safe to do so, stop the vehicle. Perform
manual DPF regeneration in a well ventilated area.
Manual DPF regeneration must be performed outdoors,
as follows. Once manual regeneration is started,
complete the regeneration in a single operation if
possible. If manual regeneration is not completed, as
indicated by the green DPF indicator going off, and the
yellow or red indicator light remains on, automatic
regeneration might not be allowed until the vehicle is
stopped and manual regeneration is performed
until completed.
1. Check engine oil and engine coolant levels to be
sure they are at proper operating levels.
2. To prevent running out of fuel during regeneration,
make sure there is at least a quarter of a tank
of fuel.
3. Check to make sure the area near the exhaust
tailpipe and under the exhaust system are clear
of any materials that could catch fire. Keep people
away from the area of the exhaust system and
exhaust gases.
2-48
4. Fully set the parking brake.
5. Shift the transmission to PARK (P) or
NEUTRAL (N).
6. Idle the engine. If you used the idling control knob
to increase the engine speed, restore it all the way
to the left to reduce the engine speed.
7. If the vehicle has Power Take Off (PTO), turn the
PTO off. SeePower Take-Off (PTO) on page 2-32.
8. Press the DPF switch in the instrument panel
switchbank. SeeInstrument Panel Switchbank
on page 3-18. The green DPF indicator light comes
on, the exhaust gas control valve operates,
engine idle speed automatically increases, and DPF
regeneration begins. Do not leave the vehicle
unattended during manual regeneration.
9. When both the green and the yellow or red DPF
indicator lights go off, regeneration is completed.
Regeneration is normally completed in about
30 minutes.Under certain operating conditions, manual regeneration
might not be able to be performed, even if the soot
level in the DPF requires regeneration. This can occur
because of low coolant temperature, low battery voltage,
or high exhaust temperature or immediately after
starting the vehicle. When manual regeneration is
requested, by pressing the DPF switch, when coolant
temperature is low, engine warm-up is started, the green
indicator light will come on, the exhaust gas control
valve operates, and engine rpm increases to help raise
engine coolant temperature. When operating conditions
allow, regeneration will start.
2-49
Instrument Panel Overview...............................3-4
Hazard Warning Flashers................................3-6
Other Warning Devices...................................3-6
Horn.............................................................3-6
Tilt Wheel.....................................................3-7
Turn Signal/Multifunction Lever.........................3-7
Turn and Lane-Change Signals........................3-8
Headlamp High/Low-Beam Changer..................3-8
Windshield Wipers..........................................3-9
Windshield Washer.......................................3-10
Cruise Control..............................................3-10
Exterior Lamps.............................................3-14
Headlamps on Reminder................................3-15
Daytime Running Lamps (DRL).......................3-15
Marker Lamps..............................................3-16
Instrument Panel Brightness...........................3-16
Dome Lamps...............................................3-16
Entry Lighting...............................................3-17
Reading Lamps............................................3-17
Instrument Panel Switchbank..........................3-18
Accessory Power Outlet(s).............................3-19
Ashtray(s) and Cigarette Lighter......................3-20
Climate Controls............................................3-20
Climate Control System.................................3-20
Outlet Adjustment.........................................3-23
Rear Heating System....................................3-24Warning Lights, Gages, and Indicators............3-24
Instrument Panel Cluster................................3-25
Speedometer and Odometer...........................3-26
Trip Odometer..............................................3-26
Tachometer.................................................3-26
Engine Speed Limiter....................................3-27
Safety Belt Reminders...................................3-27
Airbag Readiness Light..................................3-28
Airbag Off Light............................................3-29
Charging System Light..................................3-30
Voltmeter Gage............................................3-31
Service Transmission Warning Light................3-31
Range Inhibit Warning Indicator......................3-32
Brake System Warning Light..........................3-32
Anti-lock Brake System (ABS) Warning Light. . . .3-34
Trailer Antilock Brake System Warning Light.....3-34
Engine Coolant Temperature Gage..................3-35
Low Coolant Warning Light............................3-35
Wait to Start Indicator...................................3-36
Malfunction Indicator Lamp.............................3-36
Oil Pressure Gage........................................3-37
Low Oil Level Light.......................................3-38
Change Engine Oil Light................................3-38
Engine Overspeed Warning Light....................3-39
Engine Shutdown Warning Light.....................3-39
Transmission Temperature Gage.....................3-39
Section 3 Instrument Panel
3-1
How to Add Fluid
To add transmission fluid, do the following:
1. Remove the filler plug.
2. Add fluid at the filler plug hole. Add only enough
fluid to bring the fluid level up to the bottom of
the fill opening. Refer to the Maintenance
Schedule to determine the proper fluid to use.
SeePart C: Recommended Fluids and Lubricants
on page 6-31.
3. Reinstall the filler plug. Be sure the plug is fully
seated.
Engine Coolant (Caterpillar®Diesel
Engines)
If your vehicle has a Caterpillar®diesel engine, see the
Caterpillar®Diesel Engine Operation & Maintenance
Manual provided with your vehicle to find out what to
add, as well as when and how to service your cooling
system.
Engine Coolant (Gas and
DURAMAX
®/Isuzu 7.8L L6 Engines)
The cooling system in your vehicle is filled with
DEX-COOL®engine coolant. This coolant is designed
to remain in your vehicle for five years or 150,000 miles
(240 000 km), whichever occurs first, if you add only
DEX-COOL
®extended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem with
engine overheating, seeEngine Overheating on
page 5-48.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
•Give freezing protection down to−34°F (−37°C).
•Give boiling protection up to 265°F (129°C).
•Protect against rust and corrosion.
•Help keep the proper engine temperature.
•Let the warning lights and gages work as they
should.
Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
5-44
Checking Coolant
The coolant surge tank is located in the engine
compartment on the driver’s side of the vehicle.
{CAUTION:
Turning the surge tank pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. Never turn the surge tank pressure
cap — even a little — when the engine and
radiator are hot.
The vehicle must be parked on a level surface. When
your engine is cold, the coolant level should be at the
FULL COLD mark or higher.
If the low coolant warning
light comes on in the
instrument panel cluster
and stays on, it means you
are low on engine
coolant.
SeeLow Coolant Warning Light on page 3-35for further
information.
5-46
Cooling System
When you decide it is safe to lift the hood, here is what
you will see:
A. Engine Fan
B. Coolant Surge Tank
If your vehicle has a Caterpillar
®diesel engine, see the
Caterpillar®Diesel Engine Operation and Maintenance
Manual provided with your vehicle.
If the coolant inside the coolant surge tank is boiling, do
not do anything else until it cools down. The vehicle
should be parked on a level surface.The coolant level should
be at the FULL COLD
mark or higher. If it is not,
you may have a leak at
the pressure cap or in the
radiator hoses, heater
hoses, radiator, water
pump, or somewhere else
in the cooling system.
5-50