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2975-5. Using the driving support systems
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Driving
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■Turning off both TRAC and VSC systems
To turn the TRAC and VSC systems off, press and hold for more than 3
seconds while the vehicle is stopped.
The VSC OFF indicator will come on and the “TRAC OFF” is displa yed on the
multi-information display.
Press again to turn the systems back on.
Pre-collision brake assist and pre-collision braking will also be disabled. The
PCS warning light will come on and the message is shown on the multi-infor-
mation display. ( P. 237)
■ When the message is displayed on the multi-information display show-
ing that TRAC has been disab led even if has not been pressed
TRAC and hill-start assist control cannot be operated. Contact your Toyota
dealer.
■ Sounds and vibrations caused by the ABS, brake assist, VSC, TRAC and
hill-start assist control systems
Any of the following conditions may occur when the above system s are oper-
ating. None of these indicates that a malfunction has occurred.
● Vibrations may be felt through the vehicle body and steering.
● A motor sound may be heard after the vehicle comes to a stop.
● The brake pedal may pulsate slightly after the ABS is activated .
● The brake pedal may move down slightly after the ABS is activat ed.
■ ECB operating sound
ECB operating sound may be heard in the following cases, but it does not
indicate that a malfunction has occurred.
● Operating sound heard from motor compartment when the brake ped al is
operated.
● Motor sound of the brake system heard from the front part of th e vehicle
when the driver’s door is opened.
● Operating sound heard from the motor compartment when 1 or 2 mi nutes
passed after the stop of the fuel cell system.
■ EPS operation sound
When the steering wheel is operated, a motor sound (whirring so und) may be
heard. This does not indicate a malfunction.
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2985-5. Using the driving support systems
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Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the s ystem from
overheating when there is frequent steering input over an exten ded period of
time. The steering wheel may feel heavy as a result. Should thi s occur, refrain
from excessive steering input or stop the vehicle and turn the fuel cell system
off. The EPS system should return to normal within 10 minutes.
■ Automatic reactivation of TRAC and VSC systems
After turning the TRAC and VSC systems off, the systems will be automati-
cally re-enabled in the following situations:
● When the power switch is turned off
● If only the TRAC system is turned off, the TRAC will turn on wh en vehicle
speed increases
If both the TRAC and VSC systems are turned off, automatic re-e nabling will
not occur when vehicle speed increases
■ Operating conditions of hill-start assist control
When the following four conditions are met, the hill-start assi st control will
operate:
● The shift position is in a position other than P or N (when sta rting off forward/
backward on an upward incline).
● The vehicle is stopped.
● The accelerator pedal is not depressed.
● The parking brake is not engaged.
■ Automatic system cancelation of hill-start assist control
The hill-start assist control will turn off in any of the following situations:
● Shift the shift position to P or N.
● The accelerator pedal is depressed.
● The parking brake is engaged.
● Approximately 2 seconds elapse after the brake pedal is release d.
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2995-5. Using the driving support systems
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Driving
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WARNING
■The ABS does not operate effectively when
● The limits of tire gripping performance have been exceeded (suc h as
excessively worn tires on a snow covered road).
● The vehicle hydroplanes while driving at high speed on wet or s lick 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, espe cially 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
■ TRAC may not operate effectively when
Directional control and power may not be achievable while driving on slip-
pery road surfaces, even if the TRAC system is operating.
Drive the vehicle carefully in conditions where stability and p ower may be
lost.
■ Hill- start assist control does not operate effectively when
● Do not overly rely on the hill-start assist control. The hill-s tart assist control
may not operate effectively on steep inclines and roads covered with ice.
● Unlike the parking brake, hill-start assist control is not inte nded to hold the
vehicle stationary for an extended period of time. Do not attempt to use
hill-start assist control to hold the vehicle on an incline, as doing so may
lead to an accident.
■ When the TRAC, VSC and/or ABS is activated
The slip indicator flashes. Always drive carefully. Reckless dr iving may
cause an accident. Exercise particular care when the indicator flashes.
■ When the TRAC/VSC systems are turned off
Be especially careful and drive at a speed appropriate to the r oad condi-
tions. As these are the systems to help ensure vehicle stabilit y and driving
force, do not turn the TRAC/VSC systems off unless necessary.
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3005-5. Using the driving support systems
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WARNING
■Replacing tires
Make sure that all tires are of the specified size, brand, trea d pattern and
total load capacity. In addition, make sure that the tires are inflated to the
recommended tire inflation pressure level.
The ABS, TRAC and VSC systems will not function correctly if di fferent tires
are installed on the vehicle.
Contact your Toyota dealer for further information when replaci ng tires or
wheels.
■ Handling of tires and the suspension
Using tires with any kind of problem or modifying the suspensio n will affect
the driving assist systems, and may cause a system to malfuncti on.
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3015-6. Driving tips
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Driving
MIRAI_OM_USA_OM62073U
Winter driving tips
●Use washer fluid that are appropr iate to the prevailing outside tem-
peratures.
● Have a service technician inspect the condition of the 12-volt bat-
tery.
● 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 specified size and brand, and tha t chains
match the size of the tires.
Perform the following according to the driving conditions:
● Do not try to forcibly open a window or move a wiper that is fr ozen.
Pour warm water over the frozen area to melt the ice. Wipe away
the water immediately to p revent it from freezing.
● To ensure proper operation of the climate control system fan,
remove any snow that has accumulated on the air inlet vents in
front of the windshield.
● Check for and remove any excess ic e or snow that may have accu-
mulated on the exterior lights, vehicle’s roof, chassis, around the
tires or on the brakes.
● Remove any snow or mud from the bottom of your shoes before
getting in the vehicle.
Carry out the necessary preparations and inspections before
driving the vehicle in winter. Always drive the vehicle in a ma n-
ner appropriate to the prevailing weather conditions.
Preparation for winter
Before driving the vehicle
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Accelerate the vehicle slowly, keep a safe distance between you and
the vehicle ahead, and drive at a reduced speed suitable to roa d con-
ditions.
Park the vehicle and shift the shift position to P without sett ing the
parking brake. The parking brake may freeze up, preventing it f rom
being released. If the vehicle is parked without setting the pa rking
brake, make sure t o block the wheels.
Failure to do so may be dangerous because it may cause the vehi cle
to move unexpectedly, possi bly leading to an accident.
Use the correct tire chain size when mount ing the tire chains.
Chain size is regulate d for each tire size.
Side chain: 0.12 in. (3 mm) in diameter
0.39 in. (10 mm) in width
1.18 in. (30 mm) in length
Cross chain: 0.16 in. (4 mm) in diameter
0.55 in. (14 mm) in width
0.98 in. (25 mm) in length
Regulations regarding the use of tire chains vary depending on loca-
tion and type of road. Always chec k local regulations before installing
chains.
■ Tire chain installation
Observe the following precautions when installing and removing chains:
● Install and remove tire chains in a safe location.
● Install tire chains on the front tires only. Do not install tir e chains on the rear
tires.
● Install tire chains on front tires as tightly as possible. Reti ghten chains after
driving 1/4 1/2 mile (0.5 1.0 km).
● Install tire chains following the instructions provided with th e tire chains.
When driving the vehicle
When parking the vehicle
Selecting tire chains
Regulations on the use of tire chains
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Driving
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WARNING
■Driving with snow tires
Observe the following precautions to reduce the risk of acciden ts.
Failure to do so may result in a loss of vehicle control and ca use death or
serious injury.
● Use tires of the specified size.
● Maintain the recommended level of air pressure.
● Do not drive in excess of 75 mph (120 km/h), regardless of the type of
snow tires being used.
● Use snow tires on all, not just some wheels.
■ Driving with tire chains
Observe the following precautions to reduce the risk of acciden ts.
Failure to do so may result in the vehicle being unable to be d riven safely,
and may cause death or serious injury.
● Do not drive in excess of the speed limit specified for the tir e chains being
used, or 30 mph (50 km/h), whichever is lower.
● Avoid driving on bumpy road surfaces or over potholes.
● Avoid sudden acceleration, abrupt steering, sudden braking and shifting
operations that cause sudden regenerative braking.
● Slow down sufficiently before entering a curve to ensure that v ehicle con-
trol is maintained.
● Do not use LDA (Lane Departure Alert with steering control) sys tem.
NOTICE
■Repairing or replacing snow tires
Request repairs or replacement of snow tires from Toyota dealer s or legiti-
mate tire retailers.
This is because the removal and attachment of snow tires affect s the opera-
tion of the tire pressure warning valves and transmitters.
■ Fitting tire chains
The tire pressure warning valves and transmitters may not funct ion correctly
when tire chains are fitted.
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3045-6. Driving tips
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