2020 TOYOTA TUNDRA ECU

1633-4. Adjusting the steering wheel and mirrors
3
Operation of each component
When the engine switch is turned
off, the steering wheel returns to
its stowed position by moving up
and away to enable easier driver
entry and exit.
Turning the engine switch to ACC
or ON mode will return the steering
wheel to the original position.
■The steering wheel can be adjusted when (power adjustable type)
The engine switch is in ON.
■ Automatic adjustment of the stee ring position (power adjustable type)
A desired steering position can be entered to memory and recall ed automati-
cally by the driving position memory system. ( P. 152)
■ Power easy access system (vehicles with driving position memory )
The steering wheel and driver’s seat move in accordance with en gine switch
position and the driver’s seat belt condition. ( P. 152)
Auto tilt away (power-adjustable type)
WARNING
■Caution while driving
Do not adjust the steering wheel while driving.
Doing so may cause the driver to mishandle the vehicle and caus e an acci-
dent, resulting in death or serious injury.
■ After adjusting the steering wheel (manually adjustable type)
Make sure that the steering wheel is securely locked.
Otherwise, the steering wheel may move suddenly, possibly causi ng an
accident and resulting in death or serious injury.

1753-5. Opening, closing the windows and moon roof
3
Operation of each component
Back window
Open/close
Push the lock release lever and
slide the back window.
■Closing the back window
Make sure that the back window is securely closed after closing it.
: If equipped
Opening and closing
WARNING
■Caution while driving
Keep the back window closed.
This not only keeps personal belongings from being thrown out, but also
prevents exhaust gases from entering the vehicle.

1894-1. Before driving
4
Driving
WARNING
■If you hear a squealing or scrap ing noise (brake pad wear limit indica-
tors)
Have the brake pads checked and replaced by your Toyota dealer as soon
as possible.
Rotor damage may result if the pads are not replaced when neede d.
It is dangerous to drive the vehicle when the wear limits of the brake pads
and/or those of the brake discs are exceeded.
■ When the vehicle is stopped
● Do not race the engine.
If the vehicle is in any gear other than P or N, the vehicle may move sud-
denly and unexpectedly, causing an accident.
● In order to prevent accidents due to the vehicle rolling away, always keep
depressing the brake pedal while the engine is running, and app ly the
parking brake as necessary.
● If the vehicle is stopped on an incline, in order to prevent ac cidents caused
by the vehicle rolling forward or backward, always depress the brake pedal
and securely apply the parking brake as needed.
● Avoid revving or racing the engine.
Running the engine at high speed while the vehicle is stopped m ay cause
the exhaust system to overheat, which could result in a fire if combustible
material is nearby.
■ When the vehicle is parked
● Do not leave glasses, cigarette lighters, spray cans, or soft d rink cans in
the vehicle when it is in the sun.
Doing so may result in the following:
• Gas may leak from a cigarette lighter or spray can, and may le ad to a
fire.
• The temperature inside the vehicle may cause the plastic lenses and plastic material of glasses to deform or crack.
• Soft drink cans may rupture, causing the contents to spray ove r the
interior of the vehicle, and may also cause a short circuit in the vehicle’s
electrical components.
● Do not leave cigarette lighters in the vehicle. If a cigarette lighter is in a
place such as the glove box or on the floor, it may be lit acci dentally when
luggage is loaded or the seat is adjusted, causing a fire.
● Do not attach adhesive discs to the windshield or windows. Do n ot place
containers such as air fresheners on the instrument panel or da shboard.
Adhesive discs or containers may act as lenses, causing a fire in the vehi-
cle.

1904-1. Before driving
WARNING
●Do not leave a door or window open if the curved glass is coate d with a
metallized film such as a silver-colored one. Reflected sunligh t may cause
the glass to act as a lens, causing a fire.
● Always apply the parking brake, shift the shift lever to P, stop the engine
and lock the vehicle.
Do not leave the vehicle unattended while the engine is running .
If the vehicle is parked with the shift lever in P but the park ing brake is not
set, the vehicle may start to move, possibly leading to an acci dent.
● Do not touch the exhaust pipes while the engine is running or i mmediately
after turning the engine off.
Doing so may cause burns.
● 4WD models: If the shift lever is moved before the “4LO” indicator turns
on/off, the transfer mode may not be shifted completely. The tr ansfer mode
disengages both the front and rear driveshafts from the powertrain and
allows the vehicle to move regardless of the shift position. (A t this time, the
indicator blinks and the buzzer sounds.)
Therefore, the vehicle is free to roll even if the automatic transmission is in
P. You or someone else could be seriously injured. You must complete the
shifting of the transfer mode. ( P. 315)
■ When taking a nap in the vehicle
Always turn the engine off. Otherwise, if you accidentally move the shift
lever or depress the accelerator pedal, this could cause an acc ident or fire
due to engine overheating. Additionally, if the vehicle is park ed in a poorly
ventilated area, exhaust gases may collect and enter the vehicl e, leading to
death or a serious health hazard.
■ When braking
● When the brakes are wet, drive more cautiously.
Braking distance increases when the brakes are wet, and this ma y cause
one side of the vehicle to brake differently than the other sid e. Also, the
parking brake may not securely hold the vehicle.
● If the brake booster device does not operate, do not follow oth er vehicles
closely and avoid hills or shar p turns that require braking.
In this case, braking is still possible, but the brake pedal sh ould be
depressed more firmly than usual. Also, the braking distance wi ll increase.
Have your brakes fixed immediately.
● Do not pump the brake pedal if the engine stalls.
Each push on the brake pedal uses up the reserve for the power-assisted
brakes.
● The brake system consists of 2 individual hydraulic systems; if one of the
systems fails, the other will still operate. In this case, the brake pedal
should be depressed more firmly than usual and the braking dist ance will
increase. Have your brakes fixed immediately.

1944-1. Before driving
WARNING
■Things that must not be carried in the luggage compartment
The following things may cause a fire if loaded in the luggage compart-
ment:
●Receptacles containing gasoline
●Aerosol cans
■Storage precautions
Observe the following precautions.
Failure to do so may prevent the pedals from being depressed pr operly,
may block the driver’s vision, or may result in items hitting t he driver or
passengers, possibly causing an accident.
●Do not stack anything behind the front seats higher than the se at-
backs.
●Do not place cargo or luggage in or on the following locations.
• At the feet of the driver
• On the front passenger or rea r seats (when stacking items)
• On the instrument panel
• On the dashboard
• On the auxiliary box or tray that has no lid
●Secure all items in the occupant compartment.
●Never allow anyone to ride in the rear deck. It is not designed for pas-
sengers. They should ride in thei r seats with their seat belts properly
fastened. Otherwise, they are much more likely to suffer death or seri-
ous bodily injury, in the event of sudden braking, sudden swerv ing or
an accident.
■Capacity and distribution
●Do not exceed the maximum axle weight rating or the total vehic le
weight rating.
●Even if the total load of occupant’s weight and the cargo load is less
than the total load capacity, d o not apply the load unevenly. I mproper
loading may cause deterioration of steering or braking control which
may cause death or serious injury.

2124-1. Before driving
■Trailer brake controller
P. 327
■ Matching trailer ball height to trailer coupler height
■ Before towing
Check that the following conditions are met:
●Ensure that your vehicle’s tires are properly inflated. ( P. 546)
● Trailer tires are inflated according to the trailer manufacture r’s recommen-
dation.
● All trailer lights work as required by law.
● All lights work each time you connect them.
● The trailer ball is set at the proper height for the coupler on the trailer.
● The trailer is level when it is hitched.
Do not drive if the trailer is not level, and check for imprope r tongue weight,
overloading, worn suspension, or other possible causes.
● The trailer cargo is securely loaded.
● The rear view mirrors conform to all applicable federal, state/provincial or
local regulations. If they do not, install rear view mirrors ap propriate for tow-
ing purposes.
● Depress TOW/HAUL button (if equipped). ( P. 228)
● The manual headlight leveling dial is correctly adjusted. ( P. 236)
No matter which class of tow hitch
applies, for a more safe trailer hookup,
the trailer ball setup must be the proper
height for the coupler on the trailer.
Coupler
Trailer ball
1
2

2154-1. Before driving
4
Driving
WARNING
■Hitch
Trailer hitch assemblies have different weight capacities estab lished by the
hitch manufacturer. Even though the vehicle may be physically capable of
towing a higher weight, the operator must determine the maximum weight
rating of the particular hitch assembly and never exceed the ma ximum
weight rating specified for the trailer-hitch. Exceeding the ma ximum weight
rating set by the trailer-hitch manufacturer can cause an accid ent resulting
in death or serious personal injuries.
■ When towing a trailer
Toyota recommends trailers with brakes that conform to any appl icable fed-
eral and state/provincial regulations.
● If the gross trailer weight exceeds unbraked TWR, trailer brake s are
required. Toyota recommends trailers with brakes that conform t o all appli-
cable federal and state/provincial regulations.
● Never tap into your vehicle’s hydraulic system, as this will lo wer the vehi-
cle’s braking effectiveness.
● Never tow a trailer without using a safety chain securely attac hed to both
the trailer and the vehicle. If damage occurs to the coupling u nit or hitch
ball, there is danger of the trailer wandering into another lan e.
NOTICE
■When installing a trailer hitch
Use only the position recommended by your Toyota dealer. Do not install
the trailer hitch on the bumper; this may cause body damage.
■ Do not directly splice trailer lights
Do not directly splice trailer lights. Directly splicing traile r lights may damage
your vehicle’s electrical system and cause a malfunction.
■ When towing a fifth wheel trailer
Be careful not to hit the cabin or bed with
the trailer while making a sharp turn.

2224-2. Driving procedures
■Electronic key battery depletion
P. 124
■ Conditions affecting operation
P. 142
■ Note for the entry function
P. 142
■ If the engine does not start
●The engine immobilizer system may not have been deactivated. ( P. 85)
Contact your Toyota dealer.
● Check that the shift lever is securely set in P. The engine may not start if the
shift lever is displaced out of P. “Shift to P Position” will b e displayed on the
multi-information display.
■ Steering lock
After turning the engine switch off and opening and closing the doors, the
steering wheel will be locked due to the steering lock function . Operating the
engine switch again automatically cancels the steering lock.
■ When the steering lock cannot be released
■ Steering lock motor overheating prevention
To prevent the steering lock motor from overheating, operation of the motor
may be suspended if the engine is turned on and off repeatedly in a short
period of time. In this case, refrain from running the engine. After about
10 seconds, the steering lock motor will resume functioning.
■ When “Smart Entry & Start System Check” is displayed on the multi-
information display
The system may be malfunctioning. Have the vehicle inspected by your
Toyota dealer immediately.
■ If the electronic key battery is depleted
P. 449 A message will be displayed on the multi-
information display.
Check that the shift lever is in P. Press the
engine switch while turning the steering
wheel left and right.