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7-3. Do-it-yourself maintenance
■When to replace your vehicle’s tires
Tires should be replaced if:
●The treadwear indicators are showing on a tire.
● You have tire damage such as cuts, splits, cracks deep enough to expose
the fabric, and bulges indicating internal damage.
● A tire goes flat repeatedly or cannot be properly repaired due to the size or
location of a cut or other damage.
If you are not sure, consult with your Toyota dealer.
■ Replacing tires and wheels
If the ID code of the tire pressure warning valve and transmitter is not regis-
tered, the tire pressure warning system will not work properly. After driving for
about 20 minutes, the tire pressure warning light blinks for 1 minute and stays
on to indicate a system malfunction.
■ Tire life
Any tire over 6 years old must be checked by a qualified technician even if it
has seldom or never been used or damage is not obvious.
■ Routine tire inflation pressure checks
The tire pressure warning system does not replace routine tire inflation pres-
sure checks. Make sure to check tire inflation pressure as part of your routine
of daily vehicle checks.
■ Maximum load of tire
Check that the maximum load of the replacement tire is greater than 1/2 of
the Gross Axle Weight Ratings (GAWR) of either the front axle or the rear
axle, whichever is greater.
For the GAWR, see the Certification
Label. For the maximum load of the tire,
see the load limit at maximum cold tire
inflation pressure mentioned on the side-
wall of the tire. ( P. 548)
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4377-3. Do-it-yourself maintenance
7
Maintenance and care
■The initialization operation
●Make sure to carry out initialization after adjusting the tire inflation pressure.
Also, make sure the tires are cold before carrying out initialization or tire
inflation pressure adjustment.
● If you have accidentally turned the power switch off during initialization, it is
not necessary to press the reset switch again as initialization will restart
automatically when the power switch has been turned to ON mode for the
next time.
● If you accidentally press the reset switch when initialization is not necessary,
adjust the tire inflation pressure to the specified level when the tires are
cold, and conduct initialization again.
■ When initialization of the tire pressure warning system has failed
Initialization can be completed in a few minutes. However, in the following
cases, the settings have not been recorded and the system will not operate
properly. If repeated attempts to record tire inflation pressure settings are
unsuccessful, have the vehicle inspected by your Toyota dealer.
● When operating the tire pressure warning reset switch, the tire pressure
warning light does not blink 3 times.
● After carrying out the initialization procedure, the tire pressure warning light
blinks for 1 minute then stays on after driving for 20 minutes.
■ Certification for the tire pressure warning system
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7-3. Do-it-yourself maintenance
WARNING
■When inspecting or replacing tires
Observe the following precautions to prevent accidents.
Failure to do so may cause damage to parts of the drive train as well as
dangerous handling characteristics, which may lead to an accident resulting
in death or serious injury.
●Do not mix tires of different makes, models or tread patterns.
Also, do not mix tires of remarkably different treadwear.
● Do not use tire sizes other than those recommended by Toyota.
● Do not mix differently constructed ti res (radial, bias-belted or bias-ply
tires).
● Do not mix summer, all season and snow tires.
● Do not use tires that have been used on another vehicle.
Do not use tires if you do not know how they were used previously.
■ When initializing the tire pressure warning system
Do not operate the tire pressure warning reset switch without first adjusting
the tire inflation pressure to the spec ified level. Otherwise, the tire pressure
warning light may not come on even if the tire inflation pressure is low, or it
may come on when the tire inflation pressure is actually normal.
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4537-3. Do-it-yourself maintenance
7
Maintenance and care
■After a fuse is replaced
●If the lights do not turn on even after the fuse has been replaced, a bulb may
need replacement. ( P. 454)
● If the replaced fuse blows again, have the vehicle inspected by your Toyota
dealer.
■ If there is an overload in a circuit
The fuses are designed to blow, protecting the wiring harness from damage.
■ When replacing light bulbs
Toyota recommends that you use genuine Toyota products designed for this
vehicle.
Because certain bulbs are connected to circuits designed to prevent over-
load, nongenuine parts or parts not designed for this vehicle may be unus-
able.
WARNING
■To prevent system breakdowns and vehicle fire
Observe the following precautions.
Failure to do so may cause damage to the vehicle, and possibly a fire or
injury.
●Never use a fuse of a higher amperage rating than that indicated, or use
any other object in place of a fuse.
● Always use a genuine Toyota fuse or equivalent.
Never replace a fuse with a wire, even as a temporary fix.
● Do not modify the fuses or fuse boxes.
■ Fuse box near the power control unit
Never check or replace the fuses as there are high voltage parts and wiring
near the fuse box.
Doing so may cause electric shock, resulting in death or serious injury.
NOTICE
■Before replacing fuses
Have the cause of electrical overload determined and repaired by your
Toyota dealer as soon as possible.
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4677-3. Do-it-yourself maintenance
7
Maintenance and care
WARNING
■Replacing light bulbs
●Be sure to stop the hybrid system and turn off the lights. Do not attempt to
replace the bulb immediately af ter turning off the lights.
The bulbs become very hot and may cause burns.
● Do not touch the glass portion of the light bulb with bare hands. When it is
unavoidable to hold the glass portion, use and hold with a clean dry cloth
to avoid getting moisture and oils on the bulb.
Also, if the bulb is scratched or dropped, it may blow out or crack.
● Fully install light bulbs and any parts used to secure them. Failure to do so
may result in heat damage, fire, or water entering the headlight unit. This
may damage the headlights or cause condensation to build up on the lens.
● Do not attempt to repair or disassemble light bulbs, connectors, electric
circuits or component parts.
Doing so may result in death or serious injury due to electric shock.
■ To prevent damage or fire
●Make sure bulbs are fully seated and locked.
● Check the wattage of the bulb before installing to prevent heat damage.
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8When trouble arises
8-1. Essential informationEmergency flashers .......... 470
If your vehicle has to be stopped in an
emergency ...................... 471
8-2. Steps to take in an emergency
If your vehicle needs to be towed ......................... 472
If you think something is wrong .............................. 477
If a warning light turns on or a warning buzzer
sounds ............................ 478
If a warning message is displayed ......................... 487
If you have a flat tire.......... 506
If the hybrid system will not start ........................... 519
If the electronic key does not operate properly ........ 521
If the 12-volt battery is discharged ...................... 523
If your vehicle overheats ... 528
If the vehicle becomes stuck ............................... 533
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8-2. Steps to take in an emergency
If your vehicle needs to be towed
In the following situations, it is not possible to be towed by another
vehicle using cables or chains, as the front wheels may be locked due
to the parking lock. Contact your Toyota dealer or commercial towing
service.
●There is a malfunction in the shift control system. ( P. 171, 489)
● There is a malfunction in the immobilizer system. ( P. 8 3 )
● There is a malfunction in the smart key system. ( P. 521)
● The 12-volt battery is discharged. ( P. 523)
The following may indicate a problem with your hybrid transmission.
Contact your Toyota dealer or commercial towing service before tow-
ing.
● The hybrid system warning light turns on or the hybrid system
warning message is displayed on the multi-information display and
the vehicle does not move.
● The vehicle makes an abnormal sound.
Do not tow with a sling-type truck
to prevent body damage.
If towing is necessary, we recommend having your vehicle
towed by your Toyota dealer or commercial towing service,
using a wheel-lift type truck or flat bed truck.
Use a safety chain system for all towing, and abide by all state/
provincial and local laws.
Situations when it is not possible to be towed by another vehicle
Situations when it is necessary to contact dealers before towing
Towing with a sling-type truck
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PRIUS v_OM_OM47B78U_(U)
8
When trouble arises
8-2. Steps to take in an emergency
If you think something is wrong
●Fluid leaks under the vehicle
(Water dripping from the air conditioning after use is normal.)
● Flat-looking tires or uneven tire wear
● High coolant temperature warning light flashes or comes on
● Changes in exhaust sound
● Excessive tire squeal when cornering
● Strange noises related to the suspension system
● Pinging or other noises related to the hybrid system
● Engine missing, stumbling or running roughly
● Appreciable loss of power
● Vehicle pulls heavily to one side when braking
● Vehicle pulls heavily to one side when driving on a level road
● Loss of brake effectiveness, spongy feeling, pedal almost touches
the floor
If you notice any of the following symptoms, your vehicle proba-
bly needs adjustment or repair. Contact your Toyota dealer as
soon as possible.
Visible symptoms
Audible symptoms
Operational symptoms