2021 TOYOTA TUNDRA vehicle battery is discharged

5277-2. Steps to take in an emergency
7
When trouble arises
■When recharging or replacing the battery
●Vehicles with a smart key system: In some cases, it may not be possible to
unlock the doors using the smart key system when the battery is dis-
charged. Use the wireless remote control or the mechanical key to lock or
unlock the doors.
● The engine may not start on the first attempt after the battery has recharged
but will start normally after the second attempt. This is not a malfunction.
● Vehicles with a smart key system: The engine switch mode is mem orized by
the vehicle. When the battery is reconnected, the system will r eturn to the
mode it was in before the battery was discharged. Before discon necting the
battery, turn the engine switch off.
If you are unsure what mode the engine switch was in before the battery dis-
charged, be especially careful when reconnecting the battery.
WARNING
■ Avoiding battery fires or explosions
Observe the following precautions to prevent accidentally ignit ing the flam-
mable gas that may be emitted from the battery:
● Make sure each jumper cable is connected to the correct terminal and that
it is not unintentionally in contact with any other than the in tended terminal.
● Do not allow the + and - clamps of the jumper cables to come into contact
with each other.
● Do not smoke, use matches, cigarette lighters or allow open fla me near
the battery.
■ Battery precautions
The battery contains poisonous and corrosive acidic electrolyte , while
related parts contain lead and lead compounds. Observe the foll owing pre-
cautions when handling the battery:
● When working with the battery, always wear safety glasses and t ake care
not to allow any battery fluids (acid) to come into contact wit h skin, clothing
or the vehicle body.
● Do not lean over the battery.
● In the event that battery fluid comes into contact with the skin or eyes,
immediately wash the affected area with water and seek medical attention.
Place a wet sponge or cloth over the affected area until medica l attention
can be received.
● Always wash your hands after handling the battery support, term inals, and
other battery-related parts.
● Do not allow children near the battery.

5458-1. Specifications
8
Vehicle specifications
Cooling system
Capacity
Vehicles without towing package
11.4 qt. (10.8 L, 9.5 Imp.qt.)
Vehicles with towing package
12.4 qt. (11.7 L, 10.3 Imp.qt.)
Coolant typeUse either of the following.
• “Toyota Super Long Life Coolant”
• Similar high-quality ethylene glycol- based non-silicate, non-amine, non-
nitrite, and non-borate coolant with
long-life hybrid organic acid technology
Do not use plain water alone.
Ignition system
Spark plug
MakeDENSO SK20HR11
Gap0.043 in. (1.1 mm)
NOTICE
■ Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust the spark pl ug gap.
Electrical system
Battery
Open voltage at 68F
(20 C):12.6  12.8 V Fully charged
12.2
 12.4 V Half charged
11 . 8
 12.0 V Discharged
(Voltage is checked 20 minutes after the engine
and all lights are turned off.)
Charging rates5 A max.

595What to do if... (Troubleshooting)
●Is the shift lever in P? (P. 217)
●Is the battery discharged? ( P. 525)
●Did you press the engine switch while firmly depressing the bra ke pedal?
( P. 219)
●Is the shift lever in P? ( P. 222)
●Is the electronic key anywhere detectable inside the vehicle? ( P. 139)
●Is the steering wheel unlocked? (P. 222)
●Is the electronic key battery weak or depleted?
In this case, the engine can be started in a temporary way. ( P. 523)
●Is the battery discharged? (P. 525)
●Is the engine switch in ON?
If you cannot release the shift lever by depressing the brake p edal with the
engine switch in ON. ( P. 229)
If you think something is wrong
The engine does not start
(vehicles without a smart key system)
The engine does not start
(vehicles with a smart key system)
The shift lever cannot be shifted from P even if you depress
the brake pedal

599Alphabetical index
Back windowBack window ......................... 175
Power back window .............. 176
Back-up lights
Replacing light bulbs............. 468
Wattage ................................ 550
Battery ...................................... 422
If the vehicle battery is discharged .......................... 525
Preparing and checking
before winter....................... 331
Warning light ......................... 485
Blind Spot Monitor (BSM) ....... 305
Bluetooth
®*
Bottle holders .......................... 372
Brake
Fluid ...................................... 420
Parking brake........................ 233
Warning buzzer..................... 485
Warning light ......................... 485
Brake assist ............................. 320
Brake Override System ........... 185
Break-in tips ............................. 186
Brightness control Instrument panel light
control................................. 107
BSM (Blind Spot Monitor) ....... 305 Blind Spot Monitor
function ............................... 309
Rear Cross Traffic Alert function ............................... 312 Camper information ................ 588
Card holder .............................. 364
Care .................................. 400, 403
Aluminum wheels ................. 400
Exterior ................................. 400
Interior .................................. 403
Seat belts.............................. 404
Cargo capacity......................... 195
Cargo lamp Light switch ........................... 359
Replacing light bulbs ............ 470
Wattage ................................ 550
CD player
*
Certification label ............ 200, 541
Chains ...................................... 332
Child restraint system............... 59
Booster seats, definition ......... 60
Booster seats, installation....... 69
Convertible seats, definition ... 60
Convertible seats, installation ............................ 68
Front passenger occupant
classification syst em ............ 53
Infant seats, definition............. 60
Infant seats, installation .......... 67
Installing CRS with LATCH anchors ............ 65
Installing CRS with seat
belts...................................... 67
Installing CRS with top tether strap........ 70, 73
BC
*: Refer to “NAVIGATION AND MULTIMEDIA SYSTEM OWNER
’S MANUAL”.

601Alphabetical index
Doors ........................................ 127Automatic door locking and unlocking system ......... 132
Door glasses ......................... 172
Door lock............................... 130
Open door warning message ............................. 494
Outside rear view mirrors...... 167
Rear door child-protector ...... 131
Side doors............................. 127
Driver’s seat position memory .................................. 152
Drive-Start Control .................. 185
Driving ...................................... 184
Break-in tips .......................... 186
Correct driving posture ........... 32
Driving assist system ............ 320
Procedures ........................... 184
Winter drive tips .................... 331
Dynamic radar cruise control ........................ 280 Constant speed
control mode....................... 285
Vehicle-to-vehicle distance control mode ........ 287 EDR (Event data recorder)........ 11
Emergency, in case of
If the engine will not start ...... 521
If the vehicle is trappedin rising water ..................... 477
If the vehicle has discharged battery ................................ 525
If the warning buzzer sounds................................ 485
If the warning light turns
on ....................................... 485
If the warning message is displayed ........................ 493
If you have a flat tire ............. 506
If you lose your keys ............. 123
If you think something is wrong .............................. 483
If your vehicle becomes stuck ................................... 532
If your vehicle has to be stopped in an emergency ... 475
If your vehicle needs
to be towed......................... 478
If your vehicle overheats....... 529
Emergency flashers ................ 474
Engine
“ACC” position ...................... 217
Compartment ........................ 415
Engine switch ....................... 217
Hood ..................................... 414
How to start the engine......... 217
Identification number ............ 541
If the engine will not start ...... 521
Ignition switch (engine switch) ................... 217
Immobilizer system .. ............... 85
Overheating .......................... 529E
*: Refer to “NAVIGATION AND MULTIMEDIA SYSTEM OWNER
’S MANUAL”.