warning light GMC SIERRA 2023 Owner's Manual

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
122 Instruments and Controls
operation. SeeAdd-On Electrical Equipment
0 297. See your dealer if assistance is
needed.
The vehicle may not pass inspection if:
.The light is on when the engine is
running.
.The light does not come on when the
ignition is on while the engine is off.
.Critical emission control systems have not
been completely diagnosed. If this
happens, the vehicle would not be ready
for inspection and might require
several days of routine driving before the
system is ready for inspection. This can
happen if the 12-volt battery has recently
been replaced or run down, or if the
vehicle has been recently serviced.
See your dealer if the vehicle will not pass
or cannot be made ready for the test.
Brake System Warning Light
MetricEnglish This light comes on briefly when the vehicle
is turned on to show that the light is
working. If it does not come on then, have
it fixed so it will be ready to warn you if
there is a problem.
If the light comes on and stays on, there is
a brake problem. Have the brake system
inspected right away. This light may come
on if the brake fluid is low. See
Brake Fluid
0 318.
If the light comes on while driving, pull off
the road and stop carefully. The brake pedal
might be harder to push, or the brake pedal
may go closer to the floor. It could take
longer to stop. If the light is still on, have
the vehicle towed for service. See
Transporting a Disabled Vehicle 0370.
{Warning
The brake system might not be working
properly if the brake system warning
light is on. Driving with the brake system
warning light on can lead to a crash.
If the light is still on after the vehicle has
been pulled off the road and carefully
stopped, have the vehicle towed for
service.
Electric Parking Brake Light
MetricEnglish
This light comes on when the parking brake
is applied. If the light continues flashing
after the parking brake is released, or while
driving, there is a problem with the Electric
Parking Brake system. A message may also
display in the Driver Information
Center (DIC).
If the light does not come on, or remains
flashing, see your dealer.
Service Electric Parking Brake
Light

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
Instruments and Controls 123
This light should come on briefly when the
vehicle is turned on. If it does not come on,
have it fixed so it will be ready to warn if
there is a problem.
If this light stays on or comes on while
driving, there is a problem with the Electric
Parking Brake (EPB). Take the vehicle to a
dealer as soon as possible. In addition to the
parking brake, other safety functions that
utilize the EPB may also be degraded.
A message may also display in the Driver
Information Center (DIC). SeeElectric Parking
Brake 0239.
Antilock Brake System (ABS)
Warning Light
This light comes on briefly when the vehicle
is turned on to show that the light is
working. If it does not come on then, have
it fixed so it will be ready to warn you if
there is a problem. If the ABS warning light stays on, or comes
on again while driving, the vehicle needs
service. A chime may also sound when the
light stays on.
If the ABS warning light is the only light on,
the vehicle has regular brakes, but ABS is
not functioning.
If both the ABS warning light and the brake
system warning light are on, ABS is not
functioning and there is a problem with the
regular brakes. See your dealer for service.
See
Brake System Warning Light 0122.
Four-Wheel-Drive Light
Auto Mode Shown, Other Modes Similar
If equipped, the four-wheel-drive light
displays what mode the vehicle is in. The
light will show each mode: 2WD, 4HI, AUTO
(all transfer cases); 4LOW and N (two-speed
transfer case only). The light will flash when a shift is in
progress. Once the shift is complete the
light will be steady.
If the light turns amber, there may be a
malfunction with the four-wheel-drive
system. See your dealer.
See
Four-Wheel Drive 0234.
Hill Descent Control Light
If equipped, the Hill Descent Control light
comes on when the system is ready for use.
When the light flashes, the system is active.
See Hill Descent Control (HDC) 0242.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
124 Instruments and Controls
Lane Departure Warning (LDW)
Light
This light is green if LDW is on and ready to
operate.
This light changes to amber and flashes to
indicate that the lane marking has been
crossed without using a turn signal in that
direction.
SeeLane Departure Warning (LDW) 0262.
Vehicle Ahead Indicator
If equipped, this indicator will display green
when a vehicle is detected ahead and amber
when you are following a vehicle ahead
much too closely. See
Forward Collision Alert (FCA) System
0 257.
Traction Off Light
This light comes on briefly when the vehicle
is turned on to show that the light is
working. If it does not come on then, have
it fixed so it will be ready to warn you if
there is a problem.
The traction off light comes on when the
Traction Control System (TCS) has been
turned off. If Electronic Stability Control
(ESC) is turned off, TCS is also turned off. To
turn TCS and ESC off and on, see Traction
Control/Electronic Stability Control 0241.
If TCS is off, wheel slip during acceleration is
not limited unless necessary to help protect
the driveline from damage. Adjust driving
accordingly.
Traction Control System (TCS)/
Electronic Stability Control Light
This light comes on briefly when the vehicle
is turned on to show that the light is
working. If it does not come on then, have
it fixed so it will be ready to warn you if
there is a problem.
If the light is on and not flashing, the TCS
and potentially the ESC system are not fully
operational and may not assist in
maintaining control. Adjust driving
accordingly. If the condition persists, see
your dealer as soon as possible. A Driver
Information Center (DIC) message may
display.
The light flashes when the TCS and/or the
ESC system is actively working.
See Traction Control/Electronic Stability
Control 0241.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
Instruments and Controls 125
Trailer Sway Control Light (Uplevel
Cluster)
This light will flash when Trailer Sway
Control is active. SeeTrailer Sway Control
(TSC) 0285.
Electronic Stability Control (ESC)
Off Light
This light comes on briefly when the vehicle
is turned on to show that the light is
working. If it does not come on then, have
it fixed so it will be ready to warn you if
there is a problem. This light comes on when the Electronic
Stability Control (ESC) system is turned off.
If ESC is off, the Traction Control System
(TCS) is also off. To turn ESC off and on, see
Traction Control/Electronic Stability Control
0
241.
If ESC and TCS are off, the systems do not
assist in controlling the vehicle. Adjust
driving accordingly.
Engine Coolant Temperature
Warning Light
This light comes on briefly while starting
the vehicle.
If it does not, have the vehicle serviced by
your dealer. If the system is working
normally the indicator light goes off.
Caution
The engine coolant temperature warning
light indicates that the vehicle has
overheated. Driving with this light on can
damage the engine and it may not be
covered by the vehicle warranty. See
Engine Overheating 0313.
The engine coolant temperature warning
light comes on when the engine has
overheated.
If this happens, pull over and let the engine
idle. See Engine Overheating 0313.
Driver Mode Control Light
This light comes on when Snow Mode is
selected.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
Instruments and Controls 127
This light should come on briefly when the
engine starts. When the engine is off and
the vehicle is on, the light should remain
illuminated. If it does not come on under
either condition, contact your dealer.
If the light comes on and stays on when the
engine is running, it may not have adequate
oil pressure. The oil level may be low or
there may be some other oil system
problem. Turn the engine off when it is safe
to do so and contact your dealer.
Low Fuel Warning Light
A Low Fuel Warning Light near the fuel
gauge comes on briefly when the ignition is
turned on as a check to show it is working.It also comes on when the fuel gauge
indicator nears empty. The light turns off
when fuel is added. If it does not, have the
vehicle serviced.
Security Light
The security light should come on briefly as
the engine is started. If it does not come on,
have the vehicle serviced by your dealer.
If the system is working normally, the
indicator light turns off.
If the light stays on and the engine does
not start, there could be a problem with the
theft-deterrent system. See
Immobilizer
Operation 035.
High-Beam On Light
This light comes on when the high-beam
headlamps are in use. See Headlamp High/
Low-Beam Changer 0141.
IntelliBeam Light
This light comes on when the IntelliBeam
system, if equipped, is enabled. See Exterior
Lamp Controls 0139.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
Lighting 139
Lighting
Exterior Lighting
Exterior Lamp Controls . . . . . . . . . . . . . . . . 139
Exterior Lamps Off Reminder . . . . . . . . . . . 141
Headlamp High/Low-Beam Changer . . . . 141
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Daytime Running Lamps (DRL) . . . . . . . . . 141
Automatic Headlamp System . . . . . . . . . . 141
Hazard Warning Flashers . . . . . . . . . . . . . . 142
Turn and Lane-Change Signals . . . . . . . . . 143
Fog Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
Task Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . 144
Auxiliary Roof-Mounted Lamp . . . . . . . . . 144
Exterior Cargo Lamps . . . . . . . . . . . . . . . . . . 144
Interior Lighting
Instrument Panel IlluminationControl . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145
Dome Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . 145
Reading Lamps . . . . . . . . . . . . . . . . . . . . . . . . 146
Lighting Features
Entry Lighting . . . . . . . . . . . . . . . . . . . . . . . . . 146
Exit Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . 146
Battery Load Management . . . . . . . . . . . . 147
Battery Power Protection . . . . . . . . . . . . . . 147
Exterior Lighting Battery Saver . . . . . . . . 147
Exterior Lighting
Exterior Lamp Controls
The exterior lamp control is on the
instrument panel to the left of the steering
wheel.
O: Turns off the automatic headlamps and
Daytime Running Lamps (DRL). Turn the
headlamp control to
Oagain to turn the
automatic headlamps or DRL back on.
For vehicles first sold in Canada, off will only
work when the vehicle is in P (Park). AUTO :
Automatically turns on the
headlamps, parking lamps, taillamps,
instrument panel lights, roof marker lamps
(if equipped), front/rear sidemarker lamps,
and license plate lamps.
;: Turns on the parking lamps including
all lamps, except the headlamps and fog
lamps, if equipped.
For some trim levels and series of trucks
first sold in Canada, the headlamps may
turn on with the parking lamps.
2: Turns on the headlamps together with
the parking lamps, taillamps, instrument
panel lights, roof marker lamps (if
equipped), front/rear sidemarker lamps, and
license plate lamps.
When the headlamps are turned on while
the vehicle is on, the headlamps turn off
automatically 10 minutes after the ignition
is turned off. When the headlamps are
turned on while the vehicle is off, the
headlamps will stay on for 10 minutes
before turning off to prevent the battery
from being drained. Turn the headlamp
control off and then back to the headlamp
on position to make the headlamps stay on

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
142 Lighting
There is a light sensor on top of the
instrument panel. Do not cover the sensor,
otherwise the headlamps will come on when
they are not needed.
The system may also turn on the headlamps
when driving through a parking garage or
tunnel.
If the vehicle is started in a dark garage, the
automatic headlamp system comes on
immediately. If it is light outside when the
vehicle leaves the garage, there is a slight
delay before the automatic headlamp
system changes to the Daytime Running
Lamps (DRL). During that delay, the
instrument cluster may not be as bright as
usual. Make sure the instrument panelillumination control is in the full bright
position. See
Instrument Panel Illumination
Control 0145.
When it is bright enough outside, the
headlamps will turn off or may change
to DRL.
The automatic headlamp system turns off
when the exterior lamp control is turned to
Oor the ignition is off.
Lights On with Wipers
If the windshield wipers are activated in
daylight with the engine on, and the
exterior lamp control is in AUTO, the
headlamps, parking lamps, and other
exterior lamps come on. The transition time
for the lamps coming on varies based on
wiper speed. When the wipers are not
operating, these lamps turn off. Move the
exterior lamp control to
Oor;to disable
this feature.
Hazard Warning Flashers
|: Press this button to make the front
and rear turn signal lamps flash on and off.
Press again to turn the flashers off.
When the hazard warning flashers are on,
the vehicle's turn signals will not work.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/18/22
188 Infotainment System
.Some safety systems, such as Automatic
Emergency Braking, if equipped, cannot
be turned off.
.The gap setting for Adaptive Cruise
Control and alert timing for Forward
Collision Alert, if equipped, cannot be
changed.
.When trying to change a safety feature
that is not configurable in Teen Driver,
the feature may be grayed out or
removed from the infotainment menu,
or the DIC will display a message
indicating that Teen Driver is active and
the action is not available.
.Super Cruise, if equipped, is not available.
.Enhanced Low Fuel Warning (if equipped)
–When the vehicle is low on fuel, the
low fuel light on the instrument cluster
flashes and the DIC low fuel warning
cannot be dismissed.
.Do not tow a trailer if equipped with
Automatic Emergency Braking.
Report Card
The vehicle owner must secure the driver’s
consent to record certain vehicle data when
the vehicle is driven with a registered Teen
Driver key. There is one Report Card per vehicle. Data is only recorded when a
registered Teen Driver key is used to
operate the vehicle.
The Report Card data is collected from the
time Teen Driver is activated or the last
time the Report Card was reset. The
following items may be recorded:
.Distance Driven
–the total distance
driven.
.Maximum Speed –the maximum vehicle
speed detected.
.Overspeed Warnings –the number of
times the speed warning setting was
exceeded.
.Wide Open Throttle –the number of
times the accelerator pedal was pressed
nearly all the way down.
.Forward Collision Alerts (if equipped) –
the number of times the driver was
notified when approaching a vehicle
ahead too quickly and at potential risk for
a crash.
.Forward Automatic Braking, also called
Automatic Emergency Braking (if
equipped) –the number of times the
vehicle detected that a forward collision
was imminent and applied the brakes.
.Reverse Automatic Braking (if equipped) –
the number of times the vehicle detected
that a rearward collision was imminent
and applied the brakes.
.Traction Control –the number of times
the Traction Control System activated to
reduce wheel spin or loss of traction.
.Stability Control –the number of events
which required the use of electronic
stability control.
.Antilock Braking System Active –The
number of Antilock Brake System
activations.
.Tailgating Alerts (if equipped)– the
number of times the driver was alerted
for following a vehicle ahead too closely.
Report Card Data
Cumulative Data is saved for all trips until
the Report Card is reset or until the
maximum count is exceeded. If the
maximum count is exceeded for a Report
Card line item, that item will no longer be
updated in the Report Card until it is reset.
Each item will report a maximum of
1,000 counts. The distance driven will report
a maximum of 64 374 km (40,000 mi).

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
210 Driving and Operating
{Warning
Heavy braking when going down a hill
can cause your brakes to overheat and
fade. This could cause loss of control and
you or others could be injured or killed.
Apply the brakes lightly when descending
a hill and use a low gear to keep vehicle
speed under control.
If a brake fade condition is detected, a DIC
warning message is displayed. Adjust brake
pedal use and shift to a lower transmission
gear to reduce braking.
If the brakes continue to fade to a severe
condition, additional DIC messages are
displayed. The brake system warning light
will illuminate, and the vehicle speed may
be limited. See Brake System Warning Light
0 122.
If the vehicle stalls on a hill: 1. Apply the brakes to stop the vehicle, and then apply the parking brake. 2. Shift into P (Park) and then restart the
engine..If driving uphill when the vehicle
stalls, shift to R (Reverse), release the
parking brake, and back
straight down.
.Never try to turn the vehicle around.
If the hill is steep enough to stall the
vehicle, it is steep enough to cause it
to roll over.
.If you cannot make it up the hill,
back straight down the hill.
.Never back down a hill in N (Neutral)
using only the brake. The vehicle can
roll backward quickly and you could
lose control.
.If driving downhill when the vehicle
stalls, shift to a lower gear, release
the parking brake, and drive straight
down the hill.
3. If the vehicle cannot be restarted after stalling, set the parking brake, shift into
P (Park), and turn the vehicle off.
3.1. Leave the vehicle and seek help.
3.2. Stay clear of the path the vehicle would take if it rolled downhill.
{Warning
Getting out of the vehicle on the
downhill side when stopped across an
incline is dangerous. If the vehicle rolls
over, you could be crushed or killed.
Always get out on the uphill side of the
vehicle and stay well clear of the
rollover path.
Driving in Mud, Sand, Snow, or Ice
Use a low gear when driving in mud —the
deeper the mud, the lower the gear. Keep
the vehicle moving to avoid getting stuck.
Traction changes when driving on sand. On
loose sand, such as on beaches or sand
dunes, the tires tend to sink into the sand.
This affects steering, accelerating, and
braking. Drive at a reduced speed and avoid
sharp turns or abrupt maneuvers.
Traction is reduced on hard packed snow
and ice and it is easy to lose control. Reduce
vehicle speed when driving on hard packed
snow and ice.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
Driving and Operating 211
{Warning
Driving on frozen lakes, ponds, or rivers
can be dangerous. Ice conditions vary
greatly and the vehicle could fall through
the ice; you and your passengers could
drown. Drive your vehicle on safe
surfaces only.
Driving in Water
{Warning
Driving through rushing water can be
dangerous. Deep water can sweep your
vehicle downstream and you and your
passengers could drown. If it is only
shallow water, it can still wash away the
ground from under your tires. Traction
could be lost, and the vehicle could roll
over. Do not drive through rushing water.
Caution
Do not drive through standing water if it
is deep enough to cover the wheel hubs,
axles, or exhaust pipe. Deep water can
damage the axle and other vehicle parts.If the standing water is not too deep, drive
through it slowly. At faster speeds, water
can get into the engine and cause it to stall.
Stalling can occur if the exhaust pipe is
under water. Do not turn off the ignition
when driving through water. If the exhaust
pipe is under water, the engine will not
start. When going through water, the brakes
get wet and it may take longer to stop. See
“Driving on Wet Roads”
later in this section.
After Off-Road Driving
Remove any brush or debris that has
collected on the underbody or chassis,
or under the hood. These accumulations can
be a fire hazard. Reinstall underbody air
deflector and air dam if removed.
After operation in mud or sand, have the
brake linings cleaned and checked. These
substances can cause glazing and uneven
braking. Check the body structure, driveline,
steering, suspension, wheels, tires, and
exhaust system for damage and check the
fuel lines and cooling system for any
leakage.
More frequent maintenance service is
required. See theMaintenance Schedule
0 385.
Driving on Wet Roads
Rain and wet roads can reduce vehicle
traction and affect your ability to stop and
accelerate. Always drive slower in these
types of driving conditions and avoid driving
through large puddles and deep-standing or
flowing water.
{Warning
Wet brakes can cause crashes. They
might not work as well in a quick stop
and could cause pulling to one side. You
could lose control of the vehicle.
After driving through a large puddle of
water or a car/vehicle wash, lightly apply
the brake pedal until the brakes work
normally.
Flowing or rushing water creates strong
forces. Driving through flowing water
could cause the vehicle to be carried
away. If this happens, you and other
vehicle occupants could drown. Do not
ignore police warnings and be very
cautious about trying to drive through
flowing water.