Page 234 of 860

234 2-1. Driving procedures
SIENNA_U (OM45477U)
■When the “ENGINE START STOP” switch indicator flashes in amber
The system may be malfunctioning. Have the vehicle inspected by your
Toyota dealer immediately.
■ If the electronic key battery is depleted
P. 693
CAUTION
■When starting the engine
Always start the engine while sitting in the driver’s seat. Do not depress the
accelerator pedal while starting the engine under any circumstances.
Doing so may cause an accident resulting in death or serious injury.
■ Caution while driving
If the vehicle begins to slide due to engine failure or other circumstances, do
not lock or open the doors until the vehicle reaches a safe and complete
stop. Activation of the steering lock in this circumstance may lead to an acci-
dent, resulting in death or serious injury.
■ Stopping the engine in an emergency
If you want to stop the engine in an emergency while driving the vehicle,
push and hold the “ENGINE START STOP” switch for more than 3 seconds.
However, do not touch the “ENGINE START STOP” switch while driving
except in an emergency. Turning the engine off while driving will not cause
loss of steering or braking control, but the power assist to these systems will
be lost. This will make it more difficult to steer and brake, so you should pull
over and stop the vehicle as soon as it is safe to do so.
Page 235 of 860

235
2-1. Driving procedures
2
When driving
SIENNA_U (OM45477U)
NOTICE
■
To prevent battery discharge
● Do not leave the “ENGINE START STOP” switch in ACCESSORY or IGNI-
TION ON mode for long periods of time without the engine running.
● If the indicator on the “ENGINE START STOP” switch is illuminated, the
“ENGINE START STOP” switch is not off. When exiting the vehicle,
always check that the “ENGINE START STOP” switch is off.
● Do not stop the engine when the shift lever is in a position other than P. If
the engine is stopped in another shift lever position, the “ENGINE START
STOP” switch will not be turned off but instead be turned to ACCESSORY
mode. If the vehicle is left in ACCESSORY mode, battery discharge may
occur.
■ When starting the engine
● Do not race a cold engine.
● If the engine becomes difficult to start or stalls frequently, have the engine
checked immediately.
■ Symptoms indicating a malfunctio n with the “ENGINE START STOP”
switch
If the “ENGINE START STOP” seems to be operating somewhat differently
than usual, such as the switch sticking slightly, there may be a malfunction.
Contact your Toyota dealer immediately.
Page 272 of 860
272 2-3. Operating the lights and wipers
SIENNA_U (OM45477U)
■Customization that can be configured at Toyota dealer or by the multi-
information display
Settings (e.g. light sensor sensitivity) can be changed.
(Customizable features P. 815)
NOTICE
■To prevent battery discharge
Do not leave the lights on longer than necessary when the engine is not run-
ning.
Page 352 of 860

352
2-5. Driving information
SIENNA_U (OM45477U)
Winter driving tips
Carry out the necessary preparations and inspections before driving
the vehicle in winter. Always drive the vehicle in a manner appropri-
ate to the prevailing weather conditions.
■ Pre-winter preparations
●Use fluids that are appropriate to the prevailing outside tem-
peratures.
• Engine oil
• Engine coolant
• Washer fluid
● Have a service technician inspect the level and specific grav-
ity of battery electrolyte.
● Have the vehicle fitted with four snow tires or purchase a set
of tire chains for the front tires.
Ensure that all tires are the same size and brand, and that chains
match the size of the tires.
■Before driving the vehicle
Perform the following according to the driving conditions:
●Do not try to forcibly open a window or move a wiper that is
frozen. Pour warm water over the frozen area to melt the ice.
Wipe away the water immediately to prevent it from freezing.
● To ensure proper operation of th e climate control system fan,
remove any snow that has accumulated on the air inlet vents
in front of the windshield.
● Remove any ice that has accumu lated on the vehicle chassis.
● Periodically check for and remove any excess ice or snow
that may have accumulated in the wheel well or on the
brakes.
Page 387 of 860
387
3-1. Using the air conditioning system
and defogger
3
Interior features
SIENNA_U (OM45477U)
CAUTION
■To prevent the windshield from fogging up
Do not use during cool air operation in extremely humid weather. The
difference between the temperature of the outside air and that of the wind-
shield can cause the outer surface of the windshield to fog up, blocking your
vision.
NOTICE
■To prevent battery discharge
Do not leave the air conditioning system on longer than necessary when the
engine is stopped.
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397
3-1. Using the air conditioning system
and defogger
3
Interior features
SIENNA_U (OM45477U)
■When the “A/C ON” in the mu lti-information display flashes
Press
and turn off the air conditioning system before turning it on
once more. There may be a problem in the air conditioning system if the indi-
cator light continues to flash. Turn the air conditioning system off and have it
inspected by your Toyota dealer.
■ Air conditioning odors
● During use, various odors from inside and outside the vehicle may enter
into and accumulate in the air conditioning system. This may then cause
odor to be emitted from the vents.
● To reduce potential odors from occurring:
• It is recommended that the air conditioning system be set to outside air
mode prior to turning the vehicle off.
• The start timing of the blower may be delayed for a short period of time immediately after the air conditioning system is started in automatic
mode.
CAUTION
■To prevent the windshield from fogging up
Do not use during cool air operation in extremely humid weather. The
difference between the temperature of the outside air and that of the wind-
shield can cause the outer surface of the windshield to fog up, blocking your
vision.
NOTICE
■To prevent battery discharge
Do not leave the air conditioning system on longer than necessary when the
engine is stopped.
Page 400 of 860
400 3-1. Using the air conditioning system and defogger
SIENNA_U (OM45477U)
Adjusting the position of and opening and closing the air outlets
Direct air flow to the front or rear,
up or down.
NOTICE
■To prevent battery discharge
Do not leave the air conditioning system on longer than necessary when the
engine is off.
Page 404 of 860
404 3-1. Using the air conditioning system and defogger
SIENNA_U (OM45477U)
■Temperature display
The temperature display (English/U.S. Customary System and metric units)
on the trip information display can be changed. ( P. 256)
■ When the front air conditioning s ystem is in simultaneous mode
“SYNC” is shown on the display. The rear air conditioning system controls
will continue to function. ( P. 390)
NOTICE
■To prevent battery discharge
Do not leave the air conditioning system on longer than necessary when the
engine is off.