2012 TOYOTA PRIUS V electric power steering

252
2-4. Using other driving systems
PRIUS v_U (OM47784U)
Driving assist systems
To help enhance driving safety and performance, the following sys-
tems operate automatically in res ponse to various driving situations.
Be aware, however, that these systems are supplementary and
should not be relied upon too h eavily when operating the vehicle.
■ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the brakes are applied suddenly, or if
the brakes are applied while driving on a slippery road surface
■Brake assist
Generates an increased level of braking force after the brake pedal is
depressed when the system detects a panic stop situation
■VSC (Vehicle Stability Control)
Helps the driver to control skidding when swerving suddenly or turning
on slippery road surfaces
■TRAC (Traction Control)
Helps to maintain drive power and prevent the drive wheels from spin-
ning when starting the vehicle or accelerating on slippery roads
■EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to turn
the steering wheel
■Enhanced VSC (Enhanced Vehicle Stability Control)
Provides cooperative control of the ABS, TRAC, VSC and EPS.
Helps to maintain directional stability when swerving on slippery road
surfaces by controlling steering performance.
■Hill-start assist control
P. 256
■ PCS (Pre-Collision System) (if equipped)
P. 258

254 2-4. Using other driving systems
PRIUS v_U (OM47784U)
■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. 453
CAUTION
■The ABS does not operate effectively when
● Tires with inadequate gripping ability are used (such as excessively worn
tires on a snow covered road).
● The vehicle hydroplanes while driving at high speed on wet or slick road.
■ 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 in the following situ-
ations:
● 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.
Do not drive the vehicle in conditions where stability and power may be lost.
■ When the VSC is activated
The slip indicator light flashes. Always drive carefully. Reckless driving may
cause an accident. Exercise particular care when the indicator light flashes.

414 4-3. Do-it-yourself maintenance
PRIUS v_U (OM47784U)
FUSEAmpereCircuit
12 P CON MAIN 7.5A P position control system, trans-
mission
13 AM2 7.5A Power management system
14 ECU-B2 7.5A Smart key system
15 MAYDAY 10A MAYDAY
16 ECU-B3 10A Air conditioning system
17 TURN & HAZ 10A Turn signal lights
18 ETCS 10AMultiport fuel injection system/
sequential multiport fuel injection
system
19 ABS MAIN
NO.1 20A Anti-lock brake system
20 P/I 2 40AHorn, right-hand headlight (low
beam), left-hand headlight (low
beam), back-up lights
21 ABS MTR 1 30A Anti-lock brake system
22 ABS MTR 2 30A Anti-lock brake system
23 H-LP HI MAIN 20A H-LP HI RH, H-LP HI LH,
headlight switch, daytime running
light system
24 HV BATT 10A No circuit
25 DRL 7.5A Daytime running light system
26 P/I 1 60A IG2, EFI MAIN, BATT FAN
27 EPS 60A Electric power steering
28 PCU 10A Inverter and converter
29 IGCT NO.2 10A Hybrid system, P position control
system, inverter and converter

417
4-3. Do-it-yourself maintenance
PRIUS v_U (OM47784U)
4
Maintenance and care
FUSEAmpereCircuit
14 STOP 10A Stop lights, high mounted stop-
light, brake system, driver support
system, vehicle proximity notifica-
tion system
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 Panoramic roof shades
20 ECU-IG NO.1 10A Electric cooling fans, multiplex
communication system
21 ECU-IG NO.2 10A Driver support system, Pre-Colli-
sion System, inside rear view mir-
ror, garage door opener, yaw rate
& G sensor, brake system, electric
power steering, navigation system,
panoramic roof shades, tire pres-
sure warning system, seat belt
pretensioners, audio system,
emergency flashers, turn signal
lights, windshield wipers, headlight
cleaner
22 GAUGE 10AHeadlight leveling system, seat
belt reminder light, gauges and
meters
23 A/C 10A Air conditioning system
24 WASHER 15A Windshield washer
25 RR WIP 20A Rear window wiper and washer

446 5-2. Steps to take in an emergency
PRIUS v_U (OM47784U)
Have the vehicle inspected by your Toyota dealer immediately.Failure to investigate the cause of the following warnings may lead to
the system operating abnormally and possibly cause an accident.
Have the vehicle inspected by your Toyota dealer immediately.
Warning lightWarning light/Details
(U.S.A.)
(Canada) Malfunction indicator lamp
Indicates a malfunction in:
• The hybrid system;
• The electronic engine control system; or
• The electronic throttle control system
SRS warning light Indicates a malfunction in:
• The SRS airbag system;
• The front passenger occupant classification system; or
• The seat belt pretensioner system

(U.S.A.)

(Canada)
ABS warning lightIndicates a malfunction in:
• The ABS; or
• The brake assist system
Electric power steering syst em warning light (warn-
ing buzzer) Indicates a malfunction in the EPS system

5
When trouble arises
453
5-2. Steps to take in an emergency
PRIUS v_U (OM47784U)
■
Electric power steering system warning light
When the 12-volt battery charge becomes insufficient or the voltage tempo-
rarily drops, the electric power steering system warning light may come on.
■ If the malfunction indicator lamp comes on while driving
First check the following:
● Is the fuel tank empty?
If it is, fill the fuel tank immediately.
● Is the fuel tank cap loose?
If it is, tighten it securely.
The malfunction indicator lamp will go off after several driving trips.
If the malfunction indicator lamp does not go off even after several trips, con-
tact your Toyota dealer as soon as possible.
■
When the tire pressure warning light comes on
Check the tire inflation pressure and adjust to the appropriate level.
Pushing the tire pressure warning re set switch will not turn off the tire
pressure warning light.
■The tire pressure warning light may come on due to natural causes
The tire pressure warning light may come on due to natural causes such
as natural air leaks and tire inflat ion pressure changes caused by tem-
perature. In this case, adjusting the tire inflation pressure will turn off the
warning light (after a few minutes).
■When a tire is replaced with a spare tire
The compact spare tire is not equipped with a tire pressure warning
valve and transmitter. If a tire goes flat, the tire pressure warning light will
not turn off even though the flat tire has been replaced with the spare
tire. Replace the spare tire with the re paired tire and adjust the tire infla-
tion pressure. The tire pressure wa rning light will go off after a few min-
utes.

5
When trouble arises
455
5-2. Steps to take in an emergency
PRIUS v_U (OM47784U)
■If the tire pressure warning light frequently comes on after blinking
for 1 minute
If the tire pressure warning light frequently comes on after blinking for 1
minute when the “POWER” switch
is turned to ON mode, have it
checked by your Toyota dealer.
■ Customization
The vehicle speed linked seat belt reminder buzzer can be disabled.
(Customizable features  P. 525) However, Toyota recommends that the
seat belt reminder buzzer be operational to alert the driver and front passen-
ger when seat belts are not fastened.
CAUTION
■ If both the ABS and the brake system warning lights remain on
Stop your vehicle in a safe place immediately and contact your Toyota
dealer. The vehicle will become extremely unstable during braking, and the
ABS system may fail, which could cause an accident resulting in death or
serious injury.
■ When the electric power steerin g system warning light comes on
The steering wheel may become extremely heavy.
If the steering wheel becomes heavier than usual when operating, hold
firmly and operate using more force than usual.

550
PRIUS v_U (OM47784U)
Abbreviation list
Abbreviation/Acronym list
ABBREVIATIONSMEANING
A/CAir Conditioning
ABSAnti-lock Brake System
ALRAutomatic Locking Retractor
APGSAdvanced Parking Guidance System
CRSChild Restraint System
DISPDisplay
ECOEconomy/Ecology
ECUElectronic Control Unit
EDREvent Data Recorder
ELREmergency Locking Retractor
EPSElectric Power Steering
EVElectric Vehicle
GAWRGross Axle Weight Ratings
GPSGlobal Positioning System
GVWRGross Vehicle Weight Rating
I/MEmission Inspection and Maintenance
LATCHLower Anchors and Tethers for Children
LEDLight Emitting Diode
MMTMethylcyclopentadienyl Manganese Tricarbonyl
M + SMud and Snow
MTBEMethyl Tertiary Butyl Ether