TOYOTA TUNDRA 2021 (in English) Service Manual

411-1. For safe use
1
For safety and security
◆SRS front airbags
SRS driver airbag/front passenger airbag
Can help protect the head and chest of the driver and right front
passenger from impact w ith interior components
SRS knee airbags
Can help provide driver and front passenger protection
◆SRS side and curta in shield airbags
SRS side airbags
Can help protect the torso o f the front seat occupants
SRS curtain sh ield airbags
● Can help protect primarily the head of occupants in the outer
seats
● Can help prevent the occupants fro m being thrown from the vehi-
cle in the event of vehicle rollover
1
2
3
4

421-1. For safe use
SRS airbag system components
Seat belt pretensioners
Knee airbags
“AIR BAG ON” and “AIR BAG
OFF” indicator lights
Front passenger airbag
Curtain shield airbags
Side airbags (front seats)
Front passenger occupant
classification system (ECU
and sensors)
SRS warning lightDriver airbag
Driver’s seat p
osition sensor
Side impact sensors (rear)
Side impact sensors (front
door)
Driver’s seat belt buckle
switch
Front passenger’s seat belt
buckle switch
Front impact sensors
Airbag sensor assembly1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16

431-1. For safe use
1
For safety and security
Your vehicle is equipped with ADVANCED AIRBAGS designed based
on the US motor vehicle safety standards (FMVSS208). The airbag
sensor assembly (ECU) controls airbag deployment based on infor-
mation obtained from the sensors etc. shown in the system compo -
nents diagram above. This informat ion includes crash severity and
occupant information. As the airbags deploy, a chemical reactio n in
the inflators quickly fills the airbags with non-toxic gas to h elp restrain
the motion of t he occupants.
Front bench type seat: The SRS airbags are designed to protect the
driver and right front passenger, and they are not designed to protect
an occupant in the front c enter seating position.

441-1. For safe use
WARNING
■SRS airbag precautions
Observe the following precautions regarding the SRS airbags.
Failure to do so may cause death or serious injury.
● The driver and all passengers in the vehicle must wear their se at belts
properly.
The SRS airbags are supplemental devices to be used with the se at belts.
● The SRS driver airbag deploys with considerable force, and can cause
death or serious injury especially if the driver is very close to the airbag.
The National Highway Traffic Safety Administration (NHTSA) advi ses:
Since the risk zone for the driver’s airbag is the first 2 - 3 in. (50 - 75 mm)
of inflation, placing yourself 10 in. (250 mm) from your driver airbag pro-
vides you with a clear margin of safety. This distance is measured from
the center of the steering wheel to your breastbone. If you sit less than
10 in. (250 mm) away now, you can change your driving position i n sev-
eral ways:
• Move your seat to the rear as far as you can while still reach ing the ped-
als comfortably.
• Slightly recline the back of the seat. Although vehicle designs vary, many drivers can achieve the 10 in.
(250 mm) distance, even with the driver seat all the way forward , simply
by reclining the back of the seat somewhat. If reclining the ba ck of your
seat makes it hard to see the road, raise yourself by using a f irm, non-
slippery cushion, or raise the seat if your vehicle has that feature.
• If your steering wheel is adjustable, tilt it downward. This points the air- bag toward your chest instead of your head and neck.
The seat should be adjusted as recommended by NHTSA above, whil e
still maintaining control of the foot pedals, steering wheel, and your view
of the instrument panel controls.
● If the seat belt extender has been con-
nected to the front seat belt buckles but
the seat belt extender has not also been
fastened to the latch plate of the seat
belt, the SRS front airbags will judge
that the driver and front passenger are
wearing the seat belt even though the
seat belt has not been connected. In
this case, the SRS front airbags may
not activate correctly in a collision,
resulting in death or serious injury in the
event of a collision. Be sure to wear the
seat belt with the seat belt extender.

451-1. For safe use
1
For safety and security
WARNING
■SRS airbag precautions
● The SRS front passenger airbag also deploys with considerable f orce, and
can cause death or serious injury especially if the front passe nger is very
close to the airbag. The front passenger seat should be as far from the air-
bag as possible with the seatback adjusted, so the front passenger sits
upright.
● Improperly seated and/or restrained infants and children can be killed or
seriously injured by a deploying airbag. An infant or child who is too small
to use a seat belt should be properly secured using a child res traint sys-
tem. Toyota strongly recommends that all infants and children b e placed in
the rear seats of the vehicle and properly restrained. The rear seats are
safer for infants and children than the front passenger seat. ( P. 59)
●Do not sit on the edge of the seat or
lean against the dashboard.
● Do not allow a child to stand in front of
the SRS front passenger airbag unit or
sit on the knees of a front passenger.
● Do not allow the front seat occupants to
hold items on their knees.
● Do not lean against the door, the roof
side rail or the front, side and rear pil-
lars.

461-1. For safe use
WARNING
■SRS airbag precautions
● Do not hang coat hangers or other hard objects on the coat hook s. All of
these items could become projectiles and may cause death or ser ious
injury, should the SRS curtain shield airbags deploy.
● If a vinyl cover is put on the area where the SRS knee airbag w ill deploy,
be sure to remove it.
● Do not allow anyone to kneel on the
passenger seats toward the door or put
their head or hands outside the vehicle.
● Do not attach anything to or lean any-
thing against areas such as the dash-
board, steering wheel pad and lower
portion of the instrument panel.
These items can become projectiles
when the SRS driver, front passenger
and knee airbags deploy.
● Do not attach anything to areas such as
a door, windshield glass, side door
glass, front or rear pillar, roof side rail
and assist grip.
● Do not attach any heavy, sharp or hard
objects such as keys and accessories
to the key. The objects may restrict the
SRS knee airbag inflation or be thrust
into the driver’s seat area by the force
of the deploying airbag, thus causing a
danger.

471-1. For safe use
1
For safety and security
WARNING
■SRS airbag precautions
● Do not use seat accessories which cover the parts where the SRS side
airbags inflate as they may interfere with inflation of the air bags. Such
accessories may prevent the side airbags from activating correc tly, disable
the system or cause the side airbags to inflate accidentally, r esulting in
death or serious injury.
● Do not strike or apply significant levels of force to the area of the SRS air-
bag components.
Doing so can cause the SRS airbags to malfunction.
● Do not touch any of the component parts immediately after the S RS air-
bags have deployed (inflated) as they may be hot.
● If breathing becomes difficult after the SRS airbags have deplo yed, open a
door or window to allow fresh air in, or leave the vehicle if i t is safe to do
so. Wash off any residue as soon as possible to prevent skin ir ritation.
● If the areas where the SRS airbags are stored, such as the steering wheel
pad and front and rear pillar garnishes, are damaged or cracked , have
them replaced by your Toyota dealer.
● Do not place anything, such as a cushion, on the front passenger’s seat.
Doing so will disperse the passenger’s weight, which prevents t he sensor
from detecting the passenger’s weight properly. As a result, th e SRS front
airbags for the front passenger may not deploy in the event of a collision.
■ Modification and disposal of SRS airbag system components
Do not dispose of your vehicle or perform any of the following modifications
without consulting your Toyota dealer. The SRS airbags may malfunction or
deploy (inflate) accidentally, causing death or serious injury.
● Installation, removal, disassembly and repair of the SRS airbag s
● Repairs, modifications, removal or replacement of the steering wheel,
instrument panel, dashboard, seats or seat upholstery, front, s ide and rear
pillars or roof side rails
● Repairs or modifications of the front fender, front bumper, or side of the
occupant compartment
● Installation of a grille guard (bull bars, kangaroo bar, etc.), snow plows,
winches or roof luggage carrier
● Modifications to the vehicle’s suspension system
● Installation of electronic devices such as mobile two-way radio s and CD
players
● Modifications to your vehicle for a person with a physical disa bility

481-1. For safe use
■If the SRS airbags deploy (inflate)
●Slight abrasions, burns, bruising etc., may be sustained from S RS airbags,
due to the extremely high speed deployment (inflation) by hot g ases.
● A loud noise and white powder will be emitted.
● Parts of the airbag module (steering wheel hub, airbag cover an d inflator) as
well as the front seats, parts of the front and rear pillars an d roof side rails,
may be hot for several minutes. The airbag itself may also be hot.
● The windshield may crack.
● The emergency flashers will turn on automatically. (→P. 474)
● For Safety Connect subscribers, if the SRS airbags deploy or in the event of
a severe rear-end collision, the system is designed to send an emergency
call to the response center, notifying them of the vehicle’s location (without
needing to push the “SOS” button) and an agent will attempt to speak with
the occupants to ascertain the level of emergency and assistanc e required.
If the occupants are unable to communicate, the agent automatic ally treats
the call as an emergency and helps to dispatch the necessary em ergency
services. (→P. 79)
• An SRS airbag is deployed.
• A seat belt pretensioner is activated.
• The vehicle is involved in a severe rear-end collision.

491-1. For safe use
1
For safety and security
■SRS airbag deployment condi tions (SRS front airbags)
● The SRS front airbags will deploy in the event of an impact tha t exceeds the
set threshold level (the level of force corresponding to an app roximately
12 - 18 mph [20 - 30 km/h] frontal collision with a fixed wall that does not
move or deform).
However, this threshold velocity will be considerably higher in the following
situations:
• If the vehicle strikes an object, such as a parked vehicle or sign pole, which
can move or deform on impact
• If the vehicle is involved in an underride collision, such as a collision in
which the front of the vehicle “underrides”, or goes under, the bed of a truck
● Depending on the type of collision, it is possible that only th e seat belt pre-
tensioners will activate.
● The SRS front airbags for the front passenger will not activate if there is no
passenger sitting in the right front passenger seat. However, t he SRS front
airbags for the front passenger may deploy if luggage is put in the seat,
even if the seat is unoccupied. ( P. 53)
■ SRS airbag deployment conditions (SRS side and curtain shield airbags)
● The SRS side and curtain shield airbags will deploy in the even t of an
impact that exceeds the set threshold level (the level of force corresponding
to the impact force produced by an approximately 3300 lb. [1500 kg] vehicle
colliding with the vehicle cabin from a direction perpendicular to the vehicle
orientation at an approximate speed of 12 - 18 mph [20 - 30 km/ h]).
● The SRS curtain shield airbags will deploy in the event of vehi cle rollover.
● The SRS curtain shield airbags may also deploy in the event of a severe
frontal collision.

501-1. For safe use
■Conditions under which the SRS ai rbags may deploy (inflate), other than
a collision
The SRS front airbags and SRS curtain shield airbags may also d eploy if a
serious impact occurs to the underside of your vehicle. Some ex amples are
shown in the illustration.
The SRS curtain shield airbags may also deploy under the situation shown in
the illustration.
■ Types of collisions that may not deploy the SRS airbags (SRS fr ont air-
bags)
The SRS front airbags do not generally inflate if the vehicle i s involved in a
side or rear collision, if it rolls over, or if it is involved in a low-speed frontal
collision. But, whenever a collision of any type causes suffici ent forward
deceleration of the vehicle, deployment of the SRS front airbag s may occur.
●
Hitting a curb, edge of pavement or hard
surface
● Falling into or jumping over a deep hole
● Landing hard or vehicle falling
● The angle of vehicle tip-up is marginal.
● The vehicle skids and hits a curb stone.
● Collision from the side
● Collision from the rear
● Vehicle rollover