2021 GMC SIERRA airbag status

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
114 Instruments and Controls
When the vehicle is started, this light
flashes and a chime may come on to remind
passengers to fasten their seat belt.
Then the light stays on solid until the belt is
buckled. This cycle continues several times if
the front passenger remains or becomes
unbuckled while the vehicle is moving.
If the front passenger seat belt is buckled,
neither the chime nor the light comes on.
The front passenger seat belt reminder light
and chime may come on if an object is put
on the seat such as a briefcase, handbag,
grocery bag, laptop, or other electronic
device. To turn off the reminder light and/or
chime, remove the object from the seat or
buckle the seat belt.
Airbag Readiness Light
This light shows if there is an electrical
problem with the airbag system. 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, see
Airbag System061.
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 066 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

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Instruments and Controls 115
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, there may be a problem with
the lights or the passenger sensing system.
See your dealer for service.
{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. SeeAirbag Readiness Light 0114
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 (Keyless
Access) 0230 or
Ignition Positions (Key Access) 0229.
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.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./Cana-
da/Mexico-14632426) - 2021 - CRC - 11/5/20
448 Index
IndexA
Accessories and Modifications . . . . . . . . . . . 323
Accessory Power . . . . . . . . . . . . . . . . . . . . . . . . . 236
Active Fuel Management . . . . . . . . . . . . . . . . 237
Adaptive Cruise Control . . . . . . . . . . . . . . . . . . 256
Add-On Electrical Equipment . . . . . . . . . . . . . .318
Adding a Snow Plow or SimilarEquipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .318
Additional Information OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 441
Additional Maintenance and Care . . . . . . . . .415
Adjustments Lumbar, Front Seats . . . . . . . . . . . . . . . . . . . . 48
Agreements
Trademarks and License . . . . . . . . . . . . . . . 195
Air Cleaner/Filter, Engine . . . . . . . . . . . . . . . . 334
Air Conditioning . . . . . . . . . . . . . . . . . . . . 204, 206
Air Filter Life System . . . . . . . . . . . . . . . . . . . . . . . . . . . . 333
Air Filter, Passenger Compartment . . . . . . . 209
Air Vents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209
Airbag System Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
How Does an Airbag Restrain? . . . . . . . . . . 64
Passenger Sensing System . . . . . . . . . . . . . . 66
What Makes an Airbag Inflate? . . . . . . . . . 64
What Will You See after an AirbagInflates? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 Airbag System (cont'd)
When Should an Airbag Inflate? . . . . . . . . 63
Where Are the Airbags? . . . . . . . . . . . . . . . . 62
Airbags Adding Equipment to the Vehicle . . . . . . . 69
Passenger Status Indicator . . . . . . . . . . . . . . 114
Readiness Light . . . . . . . . . . . . . . . . . . . . . . . . . 114
Servicing Airbag-Equipped Vehicles . . . . . . 69
System Check . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Alarm Vehicle Security . . . . . . . . . . . . . . . . . . . . . . . . . 31
Alert
Lane Change . . . . . . . . . . . . . . . . . . . . . . . . . . . 280
Side Blind Zone (SBZA) . . . . . . . . . . . . . . . . . 280
All-Season Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 361
All-Terrain Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 362
AM-FM Radio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
Antenna Fixed Mast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
Multi-band . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
Antilock Brake System (ABS) . . . . . . . . . . . . . 246
Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Appearance Care Exterior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 398
Interior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 403
Apple CarPlay and Android Auto . . . . . . . . . .185

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./Cana-
da/Mexico-14632426) - 2021 - CRC - 11/5/20
Index 455
Mirrors (cont'd)Convex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Folding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Heated . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Manual Rearview . . . . . . . . . . . . . . . . . . . . . . . 38
Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Tilt in Reverse . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Trailer Tow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Mirrors, Interior Rearview . . . . . . . . . . . . . . . . . 38
Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 251 Driver Control . . . . . . . . . . . . . . . . . . . . . . . . . 251
Monitor System, Tire Pressure . . . . . . . . . . . 368
Multi-band Antenna . . . . . . . . . . . . . . . . . . . . . .158
N
Navigation Connected Services . . . . . . . . . . . . . . . . . . . . 445
Destination . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167
Using the System . . . . . . . . . . . . . . . . . . . . . . 163
Navigation Symbols . . . . . . . . . . . . . . . . . . . . . 166
New Vehicle Break-In . . . . . . . . . . . . . . . . . . . . 228
O
Odometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .110 Trip . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Off-Road . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
Driving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214 Oil
Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 330
Engine Oil Life System . . . . . . . . . . . . . . . . . 332
Engine Oil Pressure Gauge . . . . . . . . . . . . . . 111
Pressure Light . . . . . . . . . . . . . . . . . . . . . . . . . 122
Older Children, Restraints . . . . . . . . . . . . . . . . . . 71
Online Owner Center . . . . . . . . . . . . . . . . . . . . 430
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 439
OnStar Additional Information . . . . . . . . . . . 441
OnStar Emergency . . . . . . . . . . . . . . . . . . . . . . . 441
OnStar Overview . . . . . . . . . . . . . . . . . . . . . . . . . 440
OnStar Security . . . . . . . . . . . . . . . . . . . . . . . . . . 441
OnStar System . . . . . . . . . . . . . . . . . . . . . . 162, 173
Operating Mode Overheated Engine Protection . . . . . . . . . 340
Operation
Fog Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
Outlets Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
Overheated Engine Protection Operating Mode . . . . . . . . . . . . . . . . . . . . . . . 340
Overheating, Engine . . . . . . . . . . . . . . . . . . . . . 338
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149 Instrument Panel . . . . . . . . . . . . . . . . . . . . . . . . 4
P
ParkShifting Into . . . . . . . . . . . . . . . . . . . . . . . . . . . 236
Shifting Out of . . . . . . . . . . . . . . . . . . . . . . . . 237
Park Assist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266
Parking
Brake and P (Park) MechanismCheck . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 347
Extended . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238
Over Things That Burn . . . . . . . . . . . . . . . . . 237
Parking or Backing Assistance Systems . . . . . . . . . . . . . . . . . . . . 266
Passenger Airbag Status Indicator . . . . . . . . . 114
Passenger Compartment Air Filter . . . . . . . 209
Passenger Sensing System . . . . . . . . . . . . . . . . 66
Pedestrian Ahead Indicator . . . . . . . . . . . . . . . 119
Perchlorate Materials Requirements, California . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322
Personalization
Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Phone Apple CarPlay and Android Auto . . . . . . . 185
Bluetooth . . . . . . . . . . . . . . . . . . . . . . . . . . 180, 181
Pickup Conversion to Chassis Cab . . . . . . . . 320
Port
USB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
Positioning Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174