warning light CHEVROLET SILVERADO 2024 User Guide

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-16908339) - 2024 - CRC - 12/5/22
Seats and Restraints 67
.There is a critical problem with the airbag
system or the passenger sensing system.
When the passenger sensing system has
turned off the front outboard passenger
frontal airbag, the OFF indicator will light
and stay lit as a reminder that the airbag is
off. See Passenger Airbag Status Indicator
0 116.
The passenger sensing system is designed to
turn on the front outboard passenger frontal
airbag anytime the system senses that a
person of adult size is sitting properly in the
front outboard passenger seat.
When the passenger sensing system has
allowed the airbag to be enabled, the ON
indicator will light and stay lit as a reminder
that the airbag is active.
For some children, including children in child
restraints, and for very small adults, the
passenger sensing system may or may not
turn off the front outboard passenger
frontal airbag, depending upon the person's
seating posture and body build. Everyone in
the vehicle who has outgrown child
restraints should wear a seat belt
properly —whether or not there is an
airbag for that person.{Warning
If the airbag readiness light ever comes
on and stays on, it means that
something may be wrong with the airbag
system. To help avoid injury to yourself
or others, have the vehicle serviced right
away. See Airbag Readiness Light 0116
for more information, including important
safety information.
If the On Indicator Is Lit for a Child
Restraint
The passenger sensing system is designed to
turn off the front outboard passenger
frontal airbag if the system determines that
an infant is present in a child restraint. If a
child restraint has been installed and the ON
indicator is lit:
1. Turn the vehicle off.
2. Remove the child restraint from the vehicle.
3. Remove any additional items from the seat such as blankets, cushions, seat
covers, seat heaters, or seat massagers. 4. Reinstall the child restraint following the
directions provided by the child restraint
manufacturer and refer to Securing Child
Restraints (With the Seat Belt in the
Center Front Seat) 093 or
Securing Child Restraints (With the Seat
Belt in the Rear Seat) 087 or
Securing Child Restraints (With the Seat
Belt in the Front Passenger Seat) 091.
Make sure the seat belt retractor is
locked by pulling the shoulder belt all
the way out of the retractor when
installing the child restraint, even if the
child restraint is equipped with a seat
belt lock off. When the retractor lock is
set, the belt can be tightened but not
pulled out of the retractor.
5. If, after reinstalling the child restraint and restarting the vehicle, the ON
indicator is still lit, turn the vehicle off.
Then slightly recline the vehicle seatback
and adjust the seat cushion,
if adjustable, to make sure that the
vehicle seatback is not pushing the child
restraint into the seat cushion.
Also make sure the child restraint is not
trapped under the vehicle head restraint.
If this happens, adjust the head restraint.
See Head Restraints 044.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-16908339) - 2024 - CRC - 12/5/22
70 Seats and Restraints
system from properly turning off the
passenger airbag(s). SeePassenger Sensing
System 065.
If the vehicle has rollover roof-rail airbags,
see Different Size Tires and Wheels 0355 for
additional important information.
If a snow plow is added to the vehicle, the
airbags should still work properly. The
airbag systems were designed to work
properly under a wide range of conditions,
including snow plowing with vehicles that
have the optional snow plow prep package
(RPO VYU). Do not change or defeat the
snow plow's “tripping mechanism.” If you
do, it can damage the snow plow and the
vehicle, and may cause an airbag
deployment.
If the vehicle must be modified because you
have a disability and have questions about
whether the modifications will affect the
vehicle's airbag system, or if you have
questions about whether the airbag system
will be affected if the vehicle is modified for
any other reason, call Customer Assistance.
See Customer Assistance Offices 0401.Airbag System Check
The airbag system does not need regularly
scheduled maintenance or replacement.
Make sure the airbag readiness light is
working. See Airbag Readiness Light 0116.
Caution
If an airbag covering is damaged, opened,
or broken, the airbag may not work
properly. Do not open or break the airbag
coverings. If there are any opened or
broken airbag coverings, have the airbag
covering and/or airbag module replaced.
For the location of the airbags, see Where
Are the Airbags? 062. See your dealer
for service.
Replacing Airbag System Parts
after a Crash
{Warning
A crash can damage the airbag systems
in the vehicle. A damaged airbag system
may not properly protect you and your
passenger(s) in a crash, resulting in
serious injury or even death. To help (Continued)
Warning (Continued)
make sure the airbag systems are
working properly after a crash, have
them inspected and any necessary
replacements made as soon as possible.
If an airbag inflates, you will need to
replace airbag system parts. See your dealer
for service.
If the airbag readiness light stays on after
the vehicle is started or comes on when you
are driving, the airbag system may not work
properly. Have the vehicle serviced right
away. See Airbag Readiness Light 0116.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-16908339) - 2024 - CRC - 12/15/22
Instruments and Controls 99
Instruments and Controls
Controls
Steering Wheel Adjustment . . . . . . . . . . . 100
Heated Steering Wheel . . . . . . . . . . . . . . . . 100
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Windshield Wiper/Washer . . . . . . . . . . . . . 101
Compass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
Power Outlets . . . . . . . . . . . . . . . . . . . . . . . . . 102
Wireless Charging . . . . . . . . . . . . . . . . . . . . . 104
Warning Lights, Gauges, and Indicators
Warning Lights, Gauges, andIndicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Instrument Cluster (Base Level) . . . . . . . . 107
Instrument Cluster (Uplevel) . . . . . . . . . . . 108
Speedometer . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Odometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Trip Odometer . . . . . . . . . . . . . . . . . . . . . . . . . 111
Tachometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Fuel Gauge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Engine Oil Pressure Gauge . . . . . . . . . . . . . 112
Engine Coolant Temperature Gauge . . . . 113
Transmission Temperature Gauge (Uplevel only) . . . . . . . . . . . . . . . . . . . . . . . . 114
Voltmeter Gauge . . . . . . . . . . . . . . . . . . . . . . 114
Seat Belt Reminders . . . . . . . . . . . . . . . . . . . . 115
Airbag Readiness Light . . . . . . . . . . . . . . . . . 116
Passenger Airbag Status Indicator . . . . . . 116 Charging System Light . . . . . . . . . . . . . . . . . 117
Malfunction Indicator Lamp (Check
Engine Light) . . . . . . . . . . . . . . . . . . . . . . . . . 117
Brake System Warning Light . . . . . . . . . . . 119
Electric Parking Brake Light . . . . . . . . . . . . 119
Service Electric Parking Brake Light . . . . 119
Antilock Brake System (ABS) Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
Four-Wheel-Drive Light . . . . . . . . . . . . . . . . 120
Tow/Haul Mode Light . . . . . . . . . . . . . . . . . 120
Hill Descent Control Light . . . . . . . . . . . . . . 121
Lane Departure Warning (LDW) Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
Automatic Emergency Braking (AEB) Disabled Light . . . . . . . . . . . . . . . . . . . . . . . . 121
Vehicle Ahead Indicator . . . . . . . . . . . . . . . . 121
Pedestrian Ahead Indicator . . . . . . . . . . . . . 121
Traction Off Light . . . . . . . . . . . . . . . . . . . . . . 122
Traction Control System (TCS)/Electronic Stability Control Light . . . . . . . . . . . . . . . . 122
Electronic Stability Control (ESC) Off Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Engine Coolant Temperature Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
Driver Mode Control Light . . . . . . . . . . . . . 123
Tire Pressure Light . . . . . . . . . . . . . . . . . . . . . 123
Engine Oil Pressure Light (Uplevel Cluster) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
Low Fuel Warning Light . . . . . . . . . . . . . . . 124
Security Light . . . . . . . . . . . . . . . . . . . . . . . . . . 125 High-Beam On Light . . . . . . . . . . . . . . . . . . . 125
Front Fog Lamp Light . . . . . . . . . . . . . . . . . . 125
Lamps On Reminder . . . . . . . . . . . . . . . . . . . 125
Cruise Control Light . . . . . . . . . . . . . . . . . . . 126
Door Ajar Light . . . . . . . . . . . . . . . . . . . . . . . . 126
Information Displays
Driver Information Center (DIC) (Base
Level) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
Driver Information Center (DIC) (Uplevel) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
Head-Up Display (HUD) . . . . . . . . . . . . . . . . 130
Vehicle Messages
Vehicle Messages . . . . . . . . . . . . . . . . . . . . . . 134
Engine Power Messages . . . . . . . . . . . . . . . 134
Vehicle Speed Messages . . . . . . . . . . . . . . . 134
Universal Remote System
Universal Remote System . . . . . . . . . . . . . . 134
Universal Remote System Programming . . . . . . . . . . . . . . . . . . . . . . . . 135
Universal Remote System Operation . . . 136

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-16908339) - 2024 - CRC - 12/15/22
Instruments and Controls 103
Lift the cover to access and replace when
not in use.
{Warning
Power is always supplied to the outlets.
Do not leave electrical equipment
plugged in when the vehicle is not in use
because the vehicle could catch fire and
cause injury or death.
Caution
Leaving electrical equipment plugged in
for an extended period of time while the
vehicle is off will drain the battery.
Always unplug electrical equipment when
not in use and do not plug in equipment
that exceeds the maximum 15 amp
rating.
Certain power accessory plugs may not be
compatible with the accessory power outlet
and could overload vehicle or adapter fuses.
If a problem is experienced, see your dealer.
When adding electrical equipment, be sure
to follow the proper installation instructions
included with the equipment. See Add-On
Electrical Equipment 0300.
Caution
Hanging heavy equipment from the
power outlet can cause damage not
covered by the vehicle warranty. The
power outlets are designed for accessory
power plugs only, such as cell phone
charge cords.
Power Outlet 110/120-Volt Alternating
Current
If equipped, the vehicle has two alternating
current power outlets.
In Cab Power Outlet and DC/AC Switch
Truck Bed Power Outlet
When the ignition is on, power is supplied
to the outlets after the DC/AC switch is
pressed. A green indicator light on the
DC/AC switch indicates when the DC/AC
operation is active. One power outlet can be
used with electrical equipment that uses a
maximum of 400 watts. If both outlets are
being used, 400 watts will be shared
between the outlets. Ensure that all
connected devices do not exceed 400 watts.
The power outlet can be turned off by
pressing the DC/AC switch. The power outlet
can be turned back on after 10 seconds,
during which the indicator light on the
switch will flash.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-16908339) - 2024 - CRC - 12/15/22
104 Instruments and Controls
An indicator light on the outlet illuminates
when power is provided to the outlet and
no system fault is detected. The outlets will
not operate when the ignition is off, the
DC/AC switch is not pressed, or the plug is
not fully seated into the outlet.
If equipment is connected using more than
400 watts or a system fault is detected, a
protection circuit shuts off the power supply
and the indicator light turns off.
Do not use a power outlet with a missing or
damaged cover.
The power outlet is not designed for the
following, and may not work properly if
they are plugged in:
.Equipment with high initial peak wattage,
such as compressor-driven refrigerators
and electric power tools
.Other equipment requiring an extremely
stable power supply, such as
microcomputer-controlled electric blankets
and touch sensor lamps
.Medical equipment
Wireless Charging
If equipped and enabled, the vehicle has
wireless charging on the center console in
front of the cupholders. The system
operates at 145 kHz and wirelessly charges
one Qi compatible smartphone. The power
output of the system is capable of charging
at a rate up to 3 amp (15 W), as requested
by the compatible smartphone. SeeRadio
Frequency Statement 0407.
{Warning
Wireless charging may affect the
operation of an implanted pacemaker or
other medical devices. If you have one, it
is recommended to consult with your
doctor before using the wireless charging
system.
The vehicle must be on, in ACC/ACCESSORY,
or Retained Accessory Power (RAP) must be
active. The wireless charging feature may
not correctly indicate charging when the
vehicle is in RAP, during a Bluetooth phone
call, or when phone projection (e.g. Apple
CarPlay / Android Auto) is active. See
Retained Accessory Power (RAP) 0214. The operating temperature is
−40 °C (−40 °F)
to 85 °C (185 °F) for the charging system and
0 °C (32 °F) to 35 °C (95 °F) for the phone.
A charging stopped alert may be displayed
on the infotainment screen, if the wireless
charger or smartphone are outside of
normal operating temperature. Charging will
automatically resume when a normal
operating temperature is reached.
{Warning
Remove all objects from the charger
before charging your compatible
smartphone. Objects, such as coins, keys,
rings, paper clips, or cards, between the
smartphone and charger may become
very hot.
On the rare occasion that the charging
system does not detect an object, and
the object gets wedged between the
smartphone and charger, remove the
smartphone and allow the object to cool
before removing it from the charger, to
prevent burns.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-16908339) - 2024 - CRC - 12/15/22
106 Instruments and Controls
Freescale-WCT library
Copyright (c) 2012-2014 Freescale
Semiconductor, Inc.. All rights reserved.
Redistribution and use in source and binary
forms, with or without modification, are
permitted provided that the following
conditions are met:1. Redistributions of source code must retain the above copyright notice, this
list of conditions and the following
disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following
disclaimer in the documentation and/or
other materials provided with the
distribution.
3. Neither the name of the copyright holder nor the names of its contributors may be
used to endorse or promote products
derived from this software without
specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE
COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED
WARRANTIES, INCLUDING, BUT NOT LIMITED
TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE ARE DISCLAIMED. IN
NO EVENT SHALL THE COPYRIGHT HOLDER
OR CONTRIBUTORS BE LIABLE FOR ANY
DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO,
PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS;
OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY,
WHETHER IN CONTRACT, STRICT LIABILITY, OR
TORT (INCLUDING NEGLIGENCE OR
OTHERWISE) ARISING IN ANY WAY OUT OF
THE USE OF THIS SOFTWARE, EVEN IF
ADVISED OF THE POSSIBILITY OF SUCH
DAMAGE.Warning Lights, Gauges, and
Indicators
Warning lights and gauges can signal that
something is wrong before it becomes
serious enough to cause an expensive repair
or replacement. Paying attention to the
warning lights and gauges could prevent
injury.
Some warning lights come on briefly when
the engine is started to indicate they are
working. When one of the warning lights
comes on and stays on while driving,
or when one of the gauges shows there
may be a problem, check the section that
explains what to do. Waiting to do repairs
can be costly and even dangerous.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-16908339) - 2024 - CRC - 12/15/22
110 Instruments and Controls
Audio
Browse music, select from the favorites,
or change the audio source. Use the
thumbwheel to change the station or go to
the next or previous track.
Navigation
If there is an active route, the Turn-by-Turn
directions will appear on the Navigation
Page, if there is no active route a compass
will be displayed.
Phone
If there is no active phone call, view recent
calls, or scroll through contacts.
Options
Use the thumbwheel to scroll through items
in the Options menu.
Display Layout :Choose Classic, Progressive,
Digital, and Clean layout by pressing the
thumbwheel while the desired item is
highlighted. Exit the Layout menu by
pressing
o.
Left/Right Side Info : Press the thumbwheel
to select the items to be displayed in the
display areas. See "Left/Right Side Info"
previously in this section. Lower Gauges :
Choose one of three gauge
configurations by pressing the thumbwheel
while the desired item is highlighted. The
selected configuration will be displayed at
the bottom of the display.
Maximum displays fuel level, coolant
temperature, engine oil pressure, and
battery voltage. Transmission fluid
temperature displays instead of battery
voltage while in Tow Haul mode.
Medium displays fuel level, and coolant
temperature.
Minimum displays only the fuel level.
Info Page Options : Press the thumbwheel
to select the items to be displayed in the
Info app. See Driver Information Center (DIC)
(Base Level) 0126 orDriver Information
Center (DIC) (Uplevel) 0128.
Units : Choose US or metric units by
pressing the thumbwheel while the desired
item is highlighted.
Speed Warning : Allows the driver to set a
speed that they do not want to exceed. To
set the Speed Warning press the
thumbwheel when Speed Warning is
displayed. Use the thumbwheel to adjust
the value and press to set the speed. Once the speed is set, this feature can be
turned off by pressing the thumbwheel
while viewing this page. If the selected
speed limit is exceeded, a pop-up warning is
displayed with a chime.
Speed Sign Display :
Shows sign
information, which comes from a roadway
database in the onboard navigation system,
if equipped. The sign will show “− −”when
offline maps are unavailable. See Maps
0 160.
Head-up Display (HUD) : If equipped, this
feature allows for adjusting the angle of the
HUD image and changing or turning off the
Speed Limit Sign.
HUD Rotation: Press the thumbwheel while
Adjust Rotation is highlighted to enter
Adjust Mode. Scroll to adjust the angle of
the HUD display. Press the thumbwheel to
confirm and save the setting. This feature
may only be available in P (Park).
Speed Limit Style: Press the thumbwheel
while Speed Limit Style is highlighted to
change the speed sign style or to turn it off.
Software Information : Displays open source
software information.
Reset To Defaults : Allows the driver to
reset to default settings.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-16908339) - 2024 - CRC - 12/15/22
112 Instruments and Controls
The fuel gauge may:
.Take a little more, or less fuel to fill up
than it indicates. For example, the gauge
may have indicated the tank is half full,
but it actually takes a little more, or less
than half the tank's capacity to fill
the tank.
.Moves a little while turning a corner,
speeding up, or braking.
.Takes a few seconds to stabilize after the
ignition is turned on and goes back to
empty when the ignition is turned off.
These are normal conditions, none of which
indicate a problem with the fuel gauge.
Fuel Range
The uplevel instrument cluster has a
estimated fuel range located in the bottom
center of the display. The fuel range is
displayed with the approximate distance the
vehicle can be driven without refueling. The
fuel range estimate is based on an average
of the vehicle’s fuel economy over recent
driving history and the amount of fuel
remaining in the fuel tank.
When the estimated fuel range is low, the
range shows LOW and a message may also
display in the Driver Information
Center (DIC).
Engine Oil Pressure Gauge
Metric Base Level
English Base Level
Metric Uplevel
English Uplevel
The engine oil pressure gauge shows the
engine oil pressure in kPa (kilopascals)
or psi (pounds per square inch) when the
engine is running.
Oil pressure can vary with engine speed,
outside temperature, coolant temperature,
and oil viscosity.
On some models, the oil pump will vary
engine oil pressure according to engine
needs. Oil pressure may change quickly as
the engine speed or load varies. This is
normal. If the oil pressure warning light or
Driver Information Center (DIC) message

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
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116 Instruments and Controls
When the vehicle is started, these lights
come on solid to remind rear passengers to
fasten their seat belts. Then each light may
stay on solid or flash, and a chime may
come on if the rear passenger remains
unbuckled, or becomes unbuckled, when the
vehicle is moving. An X indicates the seat
belt is not buckled. A check mark indicates
the seat belt is buckled.
If all rear seat positions are buckled, neither
the chime nor the lights will come on.
For information on the front seat belt
reminder lights, see "Driver Seat Belt
Reminder Light" and "Front Passenger Seat
Belt Reminder Light" listed previously.
Airbag Readiness Light
This light shows if there is an electrical
problem with the airbag system. It is
located in the instrument cluster. The
system check includes the airbag sensor(s),
the passenger sensing system, the
pretensioners, the airbag modules, the
wiring, and the crash sensing and diagnostic
module. For more information on the airbag
system, seeAirbag System 060.
The airbag readiness light comes on for
several seconds when the vehicle is started.
If the light does not come on then, have it
fixed immediately.
{Warning
If the airbag readiness light stays on
after the vehicle is started or comes on
while driving, it means the airbag system
might not be working properly. The
airbags in the vehicle might not inflate in
a crash, or they could even inflate
without a crash. To help avoid injury,
have the vehicle serviced right away.
If there is a problem with the airbag
system, a Driver Information Center (DIC)
message may also come on.
Passenger Airbag Status Indicator
The vehicle has a passenger sensing system.
See Passenger Sensing System 065 for
important safety information. The overhead
console has a passenger airbag status
indicator.
United States
Canada
When the vehicle is started, the passenger
airbag status indicator will light ON and OFF,
or the symbols for on and off, for several
seconds as a system check. Then, after
several more seconds, the status indicator

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
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Instruments and Controls 117
will light either ON or OFF, or either the on
or off symbol, to let you know the status of
the front outboard passenger frontal airbag.
If the word ON or the on symbol is lit on
the passenger airbag status indicator, it
means that the front outboard passenger
frontal airbag is allowed to inflate.
If the word OFF or the off symbol is lit on
the passenger airbag status indicator, it
means that the passenger sensing system
has turned off the front outboard passenger
frontal airbag.
If, after several seconds, both status
indicator lights remain on, or if there are no
lights at all, or if the airbag readiness light
is on, there may be a problem with the
lights or the passenger sensing system. See
your dealer for service right away.
{Warning
If the airbag readiness light ever comes
on and stays on, it means that
something may be wrong with the airbag
system. To help avoid injury to yourself
or others, have the vehicle serviced right(Continued)
Warning (Continued)
away. SeeAirbag Readiness Light 0116
for more information, including important
safety information.
Charging System Light
The charging system light comes on briefly
when the ignition is turned on, but the
engine is not running, as a check to show
the light is working. It should go out when
the engine is started.
If the light stays on, or comes on while
driving, there may be a problem with the
electrical charging system. Have it checked
by your dealer. Driving while this light is on
could drain the battery.
When this light comes on, or is flashing, the
Driver Information Center (DIC) also displays
a message. If a short distance must be driven with the
light on, be sure to turn off all accessories,
such as the radio and air conditioner. Find a
safe place to stop the vehicle.
Malfunction Indicator Lamp
(Check Engine Light)
This light is part of the vehicle’s emission
control on-board diagnostic system. If this
light is on while the engine is running, a
malfunction has been detected and the
vehicle may require service. The light should
come on to show that it is working when
the ignition is on and the engine is not
running. See
Ignition Positions 0211.
Malfunctions are often indicated by the
system before any problem is noticeable.
Being aware of the light and seeking service
promptly when it comes on may prevent
damage.