
SIENNA_OM_OM08013U_(U)
2274-2. Driving procedures
4
Driving
NOTICE
■To prevent battery discharge
Do not leave the engine switch in the “ACC” or “ON” position for long peri-
ods of time without the engine running.
■ When starting the engine
●Do not crank the engine for more than 30 seconds at a time. This may
overheat the starter and wiring system.
● Do not race a cold engine.
● If the engine becomes difficult to start or stalls frequently, have the engine
checked immediately.

SIENNA_OM_OM08013U_(U)
2314-2. Driving procedures
4
Driving
■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, the motor may be sus-
pended if the engine is turned on and off repeatedly in a short period of time.
In this case, refrain from operating the engine. After about 10 seconds, the
steering lock motor will resume functioning.
■ When the engine switch indicator flashes in amber
The system may be malfunctioning. Have the vehicle inspected by your Toy-
ota dealer immediately.
■ If the electronic key battery is depleted
P. 507
■ Operation of the engine switch
●When operating the engine switch, one short, firm press is enough. If the
switch is pressed improperly, the engine may not start or the engine switch
mode may not change. It is not necessary to press and hold the switch.
● If attempting to restart the engine immediately after turning the engine
switch off, the engine may not start in some cases. After turning the engine
switch off, please wait a few seconds before restarting the engine.
The green indicator light on the engine
switch will flash and a message will be
shown on the multi-information display.
Press the engine switch while turning the
steering wheel left and right.

296
SIENNA_OM_OM08013U_(U)
4-5. Using the driving support systems
■Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the system from
overheating when there is frequent steering input over an extended period of
time. The steering wheel may feel heavy as a result. Should this occur, refrain
from excessive steering input or stop the vehicle and turn the engine off. The
EPS system should return to normal within 10 minutes.
■ Operating conditions of hill-start assist control (vehicles with a hill-start
assist control system)
When the following four conditions are met, the hill-start assist control will
operate:
●The shift lever is in a position other than P or N (when starting off forward/
backward on an upward incline).
● The vehicle is stopped.
● The accelerator pedal is not depressed.
● The parking brake is not applied.
■ Automatic system cancelation of hill-sta rt assist control (vehicles with a
hill-start assist control system)
The hill-start assist control will turn off in any of the following situations:
● The shift lever is shifted to P or N.
● The accelerator pedal is depressed.
● The parking brake is applied.
● Approximately 2 seconds elapse after the brake pedal is released.
WARNING
■ The ABS does not operate effectively when
●The limits of tire gripping performance have been exceeded (such as
excessively worn tires on a snow covered road).
● The vehicle hydroplanes while driving at high speed on wet or slick roads.
■ Stopping distance when the ABS is operating may exceed that of nor-
mal conditions
The ABS is not designed to shorten the vehicle’s stopping distance. Always
maintain a safe distance from the vehicle in front of you, especially in the
following situations:
● When driving on dirt, gravel or snow-covered roads
● When driving with tire chains
● When driving over bumps in the road
● When driving over roads with potholes or uneven surfaces

420
SIENNA_OM_OM08013U_(U)
6-1. Using the air conditioning system and defogger
Heated steering wheel/seat heaters
: If equipped
Heated steering wheel and seat heaters heat the side grips of the
steering wheel and seats, respectively.
WARNING
●Care should be taken to prevent injury if anyone in the following categories
comes in contact with the steering wheel and seats when the heater is on:
• Babies, small children, the elderly, the sick and the physically chal-
lenged
• Persons with sensitive skin
• Persons who are fatigued
• Persons who have taken alcohol or drugs that induce sleep (sleeping drugs, cold remedies, etc.)
● Observe the following precautions to prevent minor burns or overheating:
• Do not cover the seat with a blanket or cushion when using the seat
heater.
• Do not use seat heater more than necessary.
NOTICE
● Do not put heavy objects that have an uneven surface on the seat and do
not stick sharp objects (needles, nails, etc.) into the seat.
● To prevent battery discharge, do not use the functions when the engine is
not running.

531
SIENNA_OM_OM08013U_(U)
8When trouble arises
8-1. Essential informationEmergency flashers .......... 532
If your vehicle has to be stopped in an
emergency ...................... 533 8-2. Steps to take in an
emergency
If your vehicle needs to be towed ......................... 535
If you think something is wrong .............................. 539
Fuel pump shut off system ............................ 540
If a warning light turns on or a warning buzzer
sounds ............................ 541
If a warning message is displayed ......................... 550
If you have a flat tire (vehicles with
run-flat tires) .................... 566
If you have a flat tire (vehicles with a compact
spare tire) ........................ 568
If the engine will not start ................................. 582
If the shift lever cannot be shifted from P ............. 584
If the electronic key does not operate properly
(vehicles with a smart
key system) ..................... 585
If the battery is discharged ...................... 587
If your vehicle overheats ... 591
If the vehicle becomes stuck ............................... 594

591
SIENNA_OM_OM08013U_(U)
8
When trouble arises
8-2. Steps to take in an emergency
If your vehicle overheats
●The needle of the engine coolant temperature gauge ( P. 8 8 )
enters the red zone or a loss of engine power is experienced. (For
example, the vehicle sp eed does not increase.)
● The warning message indicating overheats is shown on the multi-
information display. ( P. 555)
● Steam is coming from under the hood.
Stop the vehicle in a safe place and turn off the air conditioning sys-
tem, and then stop the engine.
If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
After the engine has cooled down su fficiently, inspect the hoses and
radiator core (radiator) for any leaks.
Radiator
Cooling fans
If a large amount of coolant
leaks, immediately contact your
Toyota dealer.
The following may indicate that your vehicle is overheating.
Correction procedures
1
2
3
1
2

655Alphabetical index
SIENNA_OM_OM08013U_(U)
CareAluminum wheels.................. 465
Exterior ................................. 464
Interior................................... 467
Seat belts .............................. 467
Cargo capacity ......................... 209
Cargo hooks............................. 437
CD player
*................................ 338
Chains....................................... 314
Child restraint system ............... 56 Booster seats, definition ......... 57
Booster seats, installation ....... 68
Convertible seats, definition ............................... 57
Convertible seats, installation ............................ 66
Front passenger occupant
classification syst em............. 50
Infant seats, definition ............. 56
Infant seats, installation .......... 60
Installing CRS with LATCH anchors .............. 62, 64
Installing CRS with
seat belts .............................. 66
Installing CRS with top tether strap ............... 69, 70 Child safety ................................ 55
Airbag precautions.................. 39
Back door precautions .......... 139
Battery precautions........ 490,590
Child restraint system ............. 56
How your child should wear
the seat belt.......................... 32
Installing child restraints ......... 60
Moon roof precautions .......... 191
Power window lock switch .... 184
Power window precautions ... 186
Removed key battery
precautions......................... 509
Seat belt extender
precautions........................... 35
Seat belt precautions .............. 34
Seat heater precautions ....... 420
Sliding door child-protectors................... 125
Child-protectors ...................... 125
Cleaning
Aluminum wheels ................. 465
Exterior ................................. 464
Interior .................................. 467
Seat belts.............................. 467
Clock......................................... 440
Compass .................................. 453
Condenser................................ 487
Console box ............................. 428
Conversation mirror ................ 440
Cooling system........................ 485 Engine overheating............... 591
Cruise control
Cruise control ...................... 259
Dynamic radar cruise control ................................ 263
Cup holders ............................. 430
Curtain shield airbags............... 36
Customizable features ............ 621
C
*: Refer to “NAVIGATION AND MULTIMEDIA
SYSTEM OWNER’S MANUAL”

657Alphabetical index
SIENNA_OM_OM08013U_(U)
Emergency, in case ofIf a warning buzzer
sounds ................................ 541
If a warning light turns on...... 541
If a warning message is displayed ............................ 550
If the battery is discharged.... 587
If the electronic key does not operate properly ........... 585
If the engine will not start ...... 582
If the shift lever cannot be shifted from P ..................... 584
If you have a flat tire .... 566, 568
If you lose your keys ............. 107
If you think something is wrong.................................. 539
If your vehicle becomes
stuck ................................... 594
If your vehicle has to be stopped in an emergency ... 533
If your vehicle needs to be towed .................................. 535
If your vehicle overheats ....... 591
Engine “ACC” position ...................... 225
Accessory mode ................... 229
Compartment ........................ 482
Engine switch................ 225, 228
Hood ..................................... 479
How to start the engine......................... 225, 228
Identification number ............ 599
If the engine will not start ...... 582
Ignition switch (engine switch) ........... 225, 228
Overheating .......................... 591 Engine coolant
Capacity................................ 602
Checking............................... 485
Preparing and checking before winter ...................... 313
Engine coolant temperature gauge ....................................... 88
Engine immobilizer system ...... 75
Engine oil
Capacity................................ 600
Checking............................... 483
Oil pressure warning light ..... 541
Oil pressure warning message............................. 557
Preparing and checking before winter ...................... 313
Engine switch .................. 225, 228
EPS (Electronic Power Steering)
Function ................................ 293
Warning light......................... 542
Warning message................. 553
Event data recorder (EDR)........ 10
*: Refer to “NAVIGATION AND MULTIMEDIA
SYSTEM OWNER’S MANUAL”