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301 2-4. Using other driving systems
2
When driving
PRIUS +_OM_OM47821E_(EE)
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 hybrid
system off. The EPS system should return to normal within 10 minutes.
Electric power steering system warning light (warning buzzer)
P. 478
Operating conditions of emergency brake signal
When the following three conditions are met, the emergency brake signal
will operate:
The emergency flashers are off.
Actual vehicle speed is over 55 km/h (35 mph).
The brake pedal is depressed in a manner that cause the system to
judge from the vehicle deceleration that this is a sudden braking opera-
tion.
Automatic system cancelation of emergency brake signal
The emergency brake signal will turn off in any of the following situations:
The emergency flashers are turned on.
The brake pedal is released.
The system judges from the vehicle deceleration that is not a sudden
braking operation.
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307
2-4. Using other driving systems
2
When driving
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PCS (Pre-Crash Safety System)
: If equipped
When the radar sensor detects possibility of a frontal collision, the
pre-crash safety systems such as the brakes and seat belts are auto-
matically engaged to lessen impact to occupants as well as vehicle
damage.
Pre-crash seat belts (front seat belts only)
If the pre-crash sensor detects that a collision is unavoidable, the pre-
crash safety system will retract the seat belt before the collision occurs.
The same will happen if the driver makes an emergency braking or
loses control of the vehicle. (P. 124)
However, when the VSC system is disabled, the system will not oper-
ate in the event of skidding.
Pre-crash brake assist
When there is a high possibility of a frontal collision, the system applies
greater braking force in relation to how strongly the brake pedal is
depressed.
Pre-crash braking
When there is a high possibility of a frontal collision, the system warns
the driver using a warning light, warning display and buzzer. If the sys-
tem determines that a collision is unavoidable, the brakes are automat-
ically applied to reduce the collision speed. Pre-crash braking can be
disabled using the pre-crash braking off switch.
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308 2-4. Using other driving systems
PRIUS +_OM_OM47821E_(EE)
Disabling pre-crash braking
Pre-crash braking enabled
Pre-crash braking disabled
The “PCS” warning light will
turn on when pre-crash brak-
ing is disabled.
Radar sensor
The radar sensor detects vehi-
cles or other obstacles on or
near the road ahead and deter-
mines whether a collision is
imminent based on the position,
speed, and heading of the obsta-
cles.
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311 2-4. Using other driving systems
2
When driving
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Situations in which the pre-crash safety 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 your vehicle, such as at an inter-
section
If a vehicle suddenly cuts in front of your vehicle, such as when overtak-
ing
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-crash safety system
When a malfunction occurs due to sensor contamination, etc. that results in
the sensors being unable to detect obstacles, the pre-crash safety 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, or if the system is tempo-
rarily unusable
Warning lights will turn on or flash. (P. 472, 476)
Page 459 of 580
5When trouble arises
459
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5-1. Essential information
Emergency flashers .......... 460
If your vehicle needs
to be towed ..................... 461
If you think something is
wrong .............................. 468
5-2. Steps to take
in an emergency
If a warning light turns
on or a warning
buzzer sounds ................ 469
If you have a flat tire
(vehicles with
spare tire) ....................... 482
If you have a flat tire
(vehicles without
a spare tire) .................... 494
If the hybrid system
will not start..................... 516
If you lose your keys ......... 518
If the electronic key does not
operate properly ............. 519
If the 12-volt battery is
discharged ...................... 522
If your vehicle
overheats ........................ 528
If the vehicle becomes
stuck ............................... 534
If your vehicle has
to be stopped in
an emergency ................. 536
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468
5-1. Essential information
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If you think something is wrong
If you notice any of the following symptoms, your vehicle probably
needs adjustment or repair. Contact any authorized Toyota dealer or
repairer, or another duly qualified and equipped professional as
soon as possible.
Visible symptoms
Fluid leaks under the vehicle
(Water dripping from the air conditioning after use is normal.)
Flat-looking tires or uneven tire wear
High engine coolant temperature 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, spongy feeling, pedal almost
touches the floor
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5
469
When trouble arises
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5-2. Steps to take in an emergency
If a warning light tur ns on or a warning buzzer sounds
Stop the vehicle immediately. Continuing to drive the vehicle
may be dangerous.
The following warning indicates a possible problem in the brake sys-
tem. Immediately stop the vehicle in a safe place and contact any
authorized Toyota dealer or repairer, or another duly qualified and
equipped professional.
*1: Brake system warning buzzer:
When there is a possible problem that could affect braking performance, the
warning light will come on and a warning buzzer will sound.
*2: Parking brake engaged warning buzzer:
A buzzer will sound if the vehicle is driven at a speed of approximately 5 km/h
(3 mph) or more.
Warning lightWarning light/Details
Brake system warning light and warning buzzer (red
indicator)
*1, 2
• Low brake fluid
• Malfunction in the brake system
This light also comes on when the parking brake is not
released. If the light turns off after the parking brake is
fully released, the system is operating normally.
Calmly perform the following actions if any of the warning lights
comes on or flashes. If a light comes on or flashes, but then goes
off, this does not necessarily indicate a malfunction in the system.
However, if this continues to occur, have the vehicle inspected by
any authorized Toyota dealer or repairer, or another duly qualified
and equipped professional.
Page 470 of 580
470 5-2. Steps to take in an emergency
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Stop the vehicle immediately.
The following warning indicates the possibility of damage to the vehi-
cle that may lead to an accident. Immediately stop the vehicle in a
safe place and contact any authorized Toyota dealer or repairer, or
another duly qualified and equipped professional.
Warning lightWarning light/Details
Charging system warning light
Indicates a malfunction in the vehicle’s charging system
Low engine oil pressure warning light
Indicates that the engine oil pressure is too low
High coolant temperature warning light
Indicates that the coolant temperature is too high
Changes from a flashing to a solid light when the engine
coolant temperature increases.
Hybrid system warning light (warning buzzer)
Indicates a malfunction in the hybrid system