2012 TOYOTA PRIUS warning light

307
2-4. Using other
driving systems
2
When driving
■Obstacles not detected
The sensor cannot detect plastic obstacles such as traffic cones. There may
also be occasions when the sensor cannot detect pedestrians, animals,
bicycles, motorcycles, trees, or snowdrifts.
■ Situations in which the pre-collis ion system does not function properly
The system may not function effectively in situations such as the following:
● On roads with sharp bends or uneven surfaces
● If a vehicle suddenly moves in front of vehicle, such as at an intersection
● If a vehicle suddenly cuts in front of vehicle, such as when overtaking
● In inclement weather such as heavy rain, fog, snow or sand storms
● When your vehicle is skidding with the VSC system off
● When an extreme change in vehicle height occurs
● When the axis of the radar is out of adjustment
■ Automatic cancelation of the pre-collision system
When a malfunction occurs due to sensor contamination, etc. that results in
the sensors being unable to detect obstacles, the pre-collision system will be
automatically disabled. In this case, the system will not activate even if there
is a collision possibility.
■ When there is a malfunction in the system
Warning lights and/or warning messages will turn on or flash. ( P. 496, 509)

440 4-3. Do-it-yourself maintenance
Press and hold the tire pressure
warning reset switch until the tire
pressure warning light blinks
slowly 3 times.
Wait for a few minutes with th e “POWER” switch in ON mode
and then turn the “POWER” switch off.
Registering ID codes
The tire pressure warning valve and transmitter is equipped with a
unique ID code. When replacing a tire pressure warning valve and
transmitter, it is necessary to regi ster the ID code. Have the ID code
registered by your Toyota dealer.
STEP 4
STEP 5

441
4-3. Do-it-yourself maintenance
4
Maintenance and care
■When to replace your vehicle’s tires
Tires should be replaced if:
●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 c
annot 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
registered, the tire pre ssure 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 doe s not replace routine tire inflation
pressure checks. Make su re to check tire inflation pressure as part of
your routine of daily vehicle checks.
■Low profile tires (vehicles with 17-inch tires)
Generally, low profile tire s will wear more rapidly and tire grip perfor-
mance will be reduced on snowy and/or icy roads when compared to
standard tires. Be sure to use snow tires or tire chains on snowy and/or
icy roads and drive carefully at a speed appropriate for road and weather
conditions.

443
4-3. Do-it-yourself maintenance
4
Maintenance and care
■Initializing the tire pressure warning system
Initialize the system with the tire infl
ation pressure adjusted to the speci-
fied level.
■If the tread on snow tires wears down below 0.16 in. (4 mm)
The effectiveness of the tires as snow tires is lost.
■If you press the tire pressure warning reset switch accidentally
If initialization is performed, adjust t he tire inflation pressure to the speci-
fied level and initialize the tire pressure warning system again.
■When initialization of the tire pressure warning system has failed
Initialization can be completed in a few minutes. However, in the follow-
ing 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 pres-
sure warning light doe s not blink 3 times.
●After carrying out the initialization procedure, the tire pressure warn-
ing light blinks for 1 minute then stays on after driving for 20 minutes.

445
4-3. Do-it-yourself maintenance
4
Maintenance and care
CAUTION
■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 ma kes, 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 wa rning reset switch without first adjust-
ing the tire inflation pr essure to the specified 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 ti re inflation pressure is actually nor-
mal.

463
4-3. Do-it-yourself maintenance
4
Maintenance and care
FUSEAmpereCircuit
15 P FR DOOR 25A Power windows
16 D FR DOOR 25A Power windows
17 DOOR RR 25A Power windows
18 DOOR RL 25A Power windows
19 S/ROOF 30A Moon roof
20 ECU-IG NO.1 10A Electric cooling fans, multiplex
communication system, vehicle
proximity notification system
21 ECU-IG NO.2 10A Driver support system, Pre-Colli-
sion System, LKA system, inside
rear view mirror, garage door
opener, yaw rate & G sensor,
brake system, electric power
steering, navigation system, moon
roof, tire pressure warning system,
seat belt pretensioners, audio sys-
tem, emergency flashers, turn sig-
nal lights, windshield wipers,
headlight cleaner
22 GAUGE 10A Headlight leveling system, gauges
and meters, emergency flashers,
turn signal lights
23 A/C 10A Air conditioning system, Solar
Ventilation System, Remote Air
Conditioning System
24 WASHER 15A Windshield washer

When trouble arises5
483
5-1. Essential informationEmergency flashers ......... 484
If your vehicle needs to be towed ........................ 485
If you think something is wrong ......................... 492
5-2. Steps to take in an emergency
If a warning light turns on or a warning buzzer
sounds ........................... 493
If a warning message is displayed .................... 507
If you have a flat tire......... 523
If the hybrid system will not start .......................... 538
If you lose your keys ........ 540
If the electronic key does not operate properly....... 541
If the 12-volt battery is discharged ..................... 543
If your vehicle overheats ....................... 549
If the vehicle becomes stuck .............................. 554
If your vehicle has to be stopped in an
emergency ..................... 556

492
5-1. Essential information
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably
needs adjustment or repair. Contact your Toyota dealer as soon as
possible.
■Visible symptoms
●Fluid leaks under the vehicle
(Water dripping from the air cond itioning after use is normal.)
● Flat-looking tires or uneven tire wear
● High engine coolant temperatur e warning light flashes or
comes on
■ Audible symptoms
●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
■ Operational symptoms
●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, s pongy feeling, pedal almost
touches the floor