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WARNING LIGHTS AND CHIMES
Warning lights and gauges can alert you to a vehicle condition that may
become serious enough to cause expensive repairs. A warning light may
illuminate when a problem exists with one of your vehicle’s functions.
Many lights will illuminate when you start your vehicle to make sure the
bulb works. If any light remains on after starting the vehicle, have the
respective system inspected immediately.
Some of the warning lights shown are optional based on vehicle
equipment; your vehicle may not have some of the warning lights shown
in this section.
Service engine soon:If this light
illuminates while driving, it is a
possible indication that one of the
engine’s emission control systems
has failed.
Check suspension (if equipped):
Illuminates when the air suspension
dump switch has been activated.
SERVICE
ENGINE
SOON
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Stop engine:This light is used in
conjunction with the electronic
engine control. When illuminated,
the STOP ENGINE lamp indicates the need tostopthe engine as soon
as it can be safely done.
If the STOP ENGINE lamp begins flashing automatic engine
shutdown may take place in as little as 20 seconds.
In the event of engine shutdown, make sure the vehicle is safely
off the road and the problem is remedied prior to returning to
the road. Failure to remove the vehicle from the road could result in
an accident, causing serious injury or death.
Refer to your engine operator’s manual for specific information regarding
this feature.
If the engine shuts down, it can be restarted and operated for
30 seconds at a time or until the problem is corrected. For more
information, refer toEngine automatic shutdown warning light or
chimein theDrivingchapter of this owner guide and/or your engine
operator’s manual.
Drivers of electronically controlled engines should know the
extent of warning engine shutdown system before operating the
vehicle.
Brake reserve system warning:
Illuminates to indicate normal
Hydromax booster reserve system
activation when the engine is OFF
and the service brake pedal is
applied.
This light may also illuminate momentarily if the engine is running and
the driver turns the steering wheel fully in one direction while braking.
If the light remains on while the engine is running, this indicates
inadequate hydraulic booster pressure or reserve pump system failure.
Stop the vehicle safely as soon as possible and seek service immediately.
STOP
ENGINE
BRAKE
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Brake system warning light:To
confirm the brake system warning
light is functional, this light will
momentarily illuminate when the
ignition is turned to the ON position when the engine is not running. If
the brake system warning light does not illuminate at this time, seek
service immediately from your dealership. Illumination after starting the
vehicle indicates a pressure differential in the master cylinder and the
brake system should be inspected immediately by your dealership.
If equipped with an air brake system, the warning light stays on until the
air pressure builds up to 60 psi (414 kPa). If the air pressure drops
below 60 psi (414 kPa) during operation, the remaining brake system is
still operational but the stopping distance will be greater.
Driving a vehicle with the brake system warning light on is
dangerous. A significant decrease in braking performance may
occur. It will take you longer to stop the vehicle. Have the vehicle
checked by your dealer immediately. Driving extended distances with
the parking brake engaged can cause brake failure and the risk of
personal injury.
Wait to start:Indicates the air
intake heater is in operation and
special starting procedures are
required. Refer to theDriving
chapter.
If equipped with an air intake heater, DO NOT use ether or any
other starting fluids. The use of starting fluids (ether) in an
engine equipped with an air intake heater could result in damage
and/or personal injury.
WAIT
TO
START
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Water in fuel:During refueling, it
is possible for water-contaminated
diesel fuel to be pumped into your
tank. Your vehicle fuel system is
equipped with a fuel filter/water
separator to remove water from the fuel. The WATER IN FUEL light will
illuminate when the fuel filter/water separator has a significant quantity
of water in it.
If the light illuminates when the engine is running, stop the vehicle as
soon as safely possible, shut off the engine, then drain the fuel
filter/water separator. Refer to your engine operator’s manual for the
drain procedure. Allowing water to stay in the system could result in
extensive damage to, or failure of, the fuel injection system.
Do not drain water separator while engine is running. Fuel may
ignite if separator is drained while engine is running or vehicle is
moving.
Traction control (if equipped):
Illuminates and flashes slowly if the
Off Road mode is selected and
flashes rapidly during a traction
control event.
Differential lock:Illuminates when
the main differential is locked
(engaged).
Parking brake warning:
Momentarily illuminates when the
ignition is turned to the ON position
and the engine is off. Also
illuminates when the parking brake
is engaged. If the brake warning
lamp does not illuminate at these
times, seek service immediately.
Vehicles equipped with the Power Park (air-operated parking
brake) option:If after setting the parking brake on your vehicle the
park brake warning lamp begins to blink, this may indicate a failure in
the parking brake system. Seek service from your dealer immediately.
WATER
IN
FUEL
P
BRAKE
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Trailer ABS brake system:
Illuminates briefly when the engine
is powered-up and only when a PLC
trailer or a PLC diagnostic tool is
connected. If the light remains on
after the vehicle is started, continues to flash or fails to illuminate, have
the system serviced immediately.
Anti-lock brake system:If the
ABS light stays illuminated or
continues to flash, a malfunction has
been detected, have the system
serviced immediately. Normal
braking is still functional unless the brake warning light also is
illuminated.
Check trans (Allison automatic
transmission only):The lamp will
illuminate for several seconds after
the ignition is turned to the ON
position. Illumination of this light indicates that a problem has been
detected and shifting may be restricted. Depending upon the severity of
the problem, the read-out digit on the shifter display may be blank.
Operation may continue in order to reach service assistance. The ECU
may not respond to shift selector requests, since operating limitations
are being placed on the transmission, i.e. upshifts and downshifts may be
restricted. Direction changes will not occur.
Refer to theTransmission Operator’s Manualfor more information.
Safety belt:Reminds you to fasten
your safety belt.
Range inhibit:Illuminates when
the transmission is not engaged in
the selected gear. The warning light
will go off when the gearshift lever
is adjusted in to the appropriate gear.
Refer to theTransmission Operator’s Manualfor more information.
ABS
CHECK
TRANS
RANGE
INHIBIT
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Charging system:Illuminates when
the battery is not charging properly.
Diesel particulate filter
(Cummins engines only):
Illuminates if the soot in the DPF
has reached a level where it
requires operator assistance. Refer
toDiesel Particulate Filterin the
Maintenance and Specificationschapter and your engine operator’s
manual, for more details.
Turn signal:Illuminates when the
left or right turn signal or the
hazard lights are turned on. If the
indicators stay on or flash faster, check for a burned out bulb.
High beams:Illuminates when the
high beam headlamps are turned on.
Safety belt warning chime:Sounds when the key is in the ignition and
the driver’s safety belt is not fastened.
Key-in-ignition warning chime:Sounds when the key is left in the
ignition in the OFF/LOCK or ACC position and the driver’s door is
opened.
Headlamps on warning chime:Sounds when the headlamps or parking
lamps are on, the ignition is off (and the key is not in the ignition) and
the driver’s door is opened.
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Air pressure gauge:All vehicles
equipped with air brakes have a
dual-pointer air gauge to indicate
the pressure in each brake circuit.
The green pointer indicates the air
pressure in the primary system and
the red pointer indicates the air
pressure in the secondary system.
When the pressure is too low for
normal brake operation (less than
60 psi [414 kPa]) and the ignition is
on:
•a warning buzzer will sound and
•a warning light will illuminate in the instrument cluster
Do not drive the vehicle when the low air pressure buzzer is
sounding or the warning light is lit. These warnings indicate
there is not enough air pressure for the brake or suspension system to
operate properly.
Vehicles equipped with hydraulic brakes and an air compressor have a
single-pointer air gauge.
Note:This system doesnothave a low air pressure warning buzzer or a
low air pressure warning light.
0 30120 90 60
150AIR
PRESSURE
PSI
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Failure to inspect and if necessary replace the safety belt
assembly under the above conditions could result in severe
personal injuries in the event of a collision.
Refer toInteriorin theCleaningchapter.
Safety belt warning light and indicator chime
The safety belt warning light illuminates in the instrument cluster and a
chime sounds to remind the occupants to fasten their safety belts.
Conditions of operation
If... Then...
The driver’s safety belt is not
buckled before the ignition switch
is turned to the ON position...The safety belt warning light
illuminates 1-2 minutes and the
warning chime sounds 4-8
seconds.
The driver’s safety belt is buckled
while the indicator light is
illuminated and the warning chime
is sounding...The safety belt warning light and
warning chime turn off.
The driver’s safety belt is buckled
before the ignition switch is turned
to the ON position...The safety belt warning light and
indicator chime remain off.
Belt-Minder
The Belt-Minderfeature is a supplemental warning to the safety belt
warning function. This feature provides additional reminders to the
driver that the driver’s safety belt is unbuckled by intermittently
sounding a chime and illuminating the safety belt warning lamp in the
instrument cluster.
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