power steering Lexus IS250C 2014 User Guide

455
4-3. Do-it-yourself maintenance
4
Maintenance and care
IS250C/350C_U
Fuse layout and amperage ratings■ Engine compartment (type A fuse box)
FuseAmpereCircuit
1TURN-HAZ15 AEmergency flashers, turn signals
2IG2 MAIN20 AIG2, IGN, GAUGE
3RAD NO.230 AAudio
4D/C CUT20 ADOME, MPX-B
5RAD NO.130 AAudio
6MPX-B10 A
Headlights, front fog lights, parking
lights, license plate lights, windshield
washer, power windows, power seats,
electric tilt and telescopic steering
column, meter, smart access system
with push-button start, outside rear
view mirrors, air conditioning system,
retractable hardtop, clock
7DOME10 AInterior lights, meter, outer foot lights
8CDS10 APo w e r s o u rc e

461
4-3. Do-it-yourself maintenance
4
Maintenance and care
IS250C/350C_U
10ECU-IG LH10 A
Cruise control, air conditioning sys-
tem, power steering, rain sensor, anti-
glare inside rear view mirror, shift lock
system, tire inflation pressure warning
system, vehicle stability control
11FR S/HTR LH15 ASeat heaters and ventilators, air condi-
tioning system
12FR DOOR LH20 APower windows, outside rear view
mirrors
13SECURITY7. 5 ASmart access system with push-button
start
14H-LP LVL7. 5 AAutomatic head light leveling system
15LH-IG10 A
Charging system, headlight cleaner,
rear window defogger, electric cool-
ing fans, emergency flashers, turn sig-
nal lights, back-up lights, stop lights,
mirror heaters, seat belt pretensioner,
intuitive parking assist, cruise control,
PTC heater, exhaust system, smart
access system with push-button start
16FR WIP30 AWindshield wipers
FuseAmpereCircuit

463
4-3. Do-it-yourself maintenance
4
Maintenance and care
IS250C/350C_U
10CIG15 ACigarette lighter
11PWR OUTLET15 APo w e r o u t l e t
12FR DOOR RH20 APo w e r w i n d o w s , o u t s i d e r e a r v i e w
mirrors
13AM27. 5 AStarting system
14RH-IG7. 5 A
Seat belt pretensioner, intuitive park-
ing assist, automatic transmission, seat
heater and ventilator
15FR S/HTR RH15 ASeat heaters and ventilators, air condi-
tioning system
16ECU-IG RH10 A
Power seats, headlights, front fog
lights, parking lights, license plate
lights, front side marker lights, wind-
shield washer, outside rear view mir-
rors, VDIM, air conditioning system,
pre-collision seat belt, electric tilt and
telescopic steering, power windows,
navigation system, vehicle stability
control, retractable hardtop, clock
FuseAmpereCircuit

484
5-1. Essential information
IS250C/350C_U
■Emergency towing procedureRelease the parking brake.
Shift the shift lever to N.
Put the “ENGINE START STOP” switch in ACCESSORY mode or IGNI-
TION ON mode.
CAUTION
■Caution while towing
●Use extreme caution when towing the vehicle.
Avoid sudden starts or erratic driving maneuvers which place excessive stress on
the emergency towing eyelets and the cables or chains. Always be cautious of the
surroundings and other vehicles while towing.
●If the engine is not running, the power assist for the brakes and steering will not
function, making steering and braking more difficult.
NOTICE
■To prevent causing serious damage to the transmission
Never tow this vehicle from the front with the rear wheels on the ground.
This may cause serious damage to the transmission.
STEP1
STEP2
STEP3

492
5-2. Steps to take in an emergency
IS250C/350C_U
Have the vehicle inspected by your Lexus dealer immediately.Failing 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 Lexus dealer immediately.
Warning lightWarning light/Details
(U.S.A.)
(Canada)
Malfunction indicator lamp Indicates a malfunction in:
• The electronic engine control system;
• The electronic throttle control system; or
• The electronic automatic transmission control system.
SRS warning lightIndicates a malfunction in:
• The SRS airbag system; or
• The seat belt pretensioner system.
(U.S.A.)
(Canada)
“ABS” warning lightIndicates a malfunction in:
•The ABS;
• The brake assist system.
Electric power steering system warning lightIndicates a malfunction in the EPS (Electric Power Steering)
system.
Pre-collision system warning light (if equipped)
Indicates a malfunction in the pre-collision system.
The warning light will operate as follows, even when the sys-
tem is not malfunctioning:
• The light will flash quickly when the system is operating. (→ P. 222)
• The light will flash when the pre-collision braking is dis-
abled. ( →P. 223)
• The light will flash when the system cannot temporarily be used. ( →P. 5 0 3 )

5
When trouble arises
495
5-2. Steps to take in an emergency
IS250C/350C_U
■If the malfunction indicator lamp comes on while driving
First check the following:
●Is the fuel empty?
If it is, fill the fuel tank immediately.
●Is the fuel tank cap loose?
If it is, tighten it securely.
The lamp will go off after taking several driving trips.
If the lamp does not go off even after several trips, contact your Lexus dealer as
soon as possible.
■Electric power steering system warning light
When the voltage is low or drops, the electric power steering system warning light
may come on.
■Front passenger detection sensor and pass enger seat belt reminder and warning
buzzer
●If luggage is placed on the front passenger seat, the front passenger detection
sensor may cause the warning light to flash and the warning buzzer to sound,
even if a passenger is not sitting in the seat.
●If a cushion is placed on the seat, the sensor may not detect a passenger, and the
warning light may not operate properly.
■When the tire pressure warning light comes on
Check the tire inflation pressure and adjust to the appropriate level. Pressing the
satellite switch does not turn off the tire pressure warning light.

5
When trouble arises
497
5-2. Steps to take in an emergency
IS250C/350C_U
■If the open retractable hardtop warning buzzer sounds
Immediately stop the vehicle in a safe place and open or close the retractable hard-
top fully.
CAUTION
■When the electric power steering 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.
■If the tire pressure warning light comes on
Be sure to observe the following precautions. Failure to do so could cause loss of
vehicle control and result in death or serious injury.Vehicles with run-flat tires
• Decelerate to the lowest appropriate speed as soon as possible. Do not drive over 50 mph (80 km/h).
• Check and adjust the tire inflation pressure immediately.
• If the tire pressure warning light comes on even after tire inflation pressure adjustment, it is probable that you have a flat tire. Have the tire replaced by
the nearest Lexus dealer.
• Avoid abrupt maneuvering and braking. If the vehicle tires deteriorate, you could lose control of the steering wheel or the brakes.
Vehicles with standard tires
• Stop your vehicle in a safe place as soon as possible. Adjust the tire inflation pressure immediately.
• If the tire pressure warning light comes on even after tire inflation pressure adjustment, it is probable that you have a flat tire. Check the tires. If the tire is
flat, change to the spare tire and have the flat tire repaired by the nearest
Lexus dealer.
• Avoid abrupt maneuvering and braking. If the vehicle tires deteriorate, you
could lose control of the steering wheel or the brakes.
■If a blowout or sudden air leakage should occur
The tire pressure warning system may not activate immediately.

550
5-2. Steps to take in an emergency
IS250C/350C_U
If your vehicle has to be stopped in an emergency
CAUTION
■If the engine has to be turned off while driving
Power assist for the brakes and steering wheel will be lost, making the brake pedal
harder to depress and the steering wheel heavier to turn. Decelerate as much as
possible before turning off the engine.
Only in an emergency, such as if it becomes impossible to stop the vehicle
in the normal way, stop the vehicle using the following procedure:
Steadily step on the brake pedal with both feet and firmly
depress it.
Do not pump the brake pedal repeatedly as this will increase the
effort required to slow the vehicle.
Shift the shift lever to N.
If the shift lever is shifted to N After slowing down, stop the vehicle in a safe place by the road.
Stop the engine.
If the shift lever cannot be shifted to N Keep depressing the brake pedal with both feet to reduce vehi-
cle speed as much as possible.
Stop the engine by pressing and
holding the “ENGINE START
STOP” switch for 2 consecutive
seconds or more, or press it
briefly 3 times or more in suc-
cession.
Stop the vehicle in a safe place by the road.
STEP1
STEP2
STEP3
STEP4
STEP3
Press and hold for 2 seconds or more,
or press briefly 3 times or more
STEP4
STEP5

579
6-1. Specifications
6
Vehicle specifications
IS250C/350C_U■
Temperature A, B, C
The temperature grades are A (the highest), B, and C, representing
the tire's resistance to the generation of heat and its ability to dissipate
heat when tested under controlled conditions on a specified indoor
laboratory test wheel.
Sustained high temperature can cause the material of the tire to degenerate
and reduce tire life, and excessive temperature can lead to sudden tire fail-
ure.
The grade C corresponds to a level of performance which all passenger car
tires must meet under the Federal Motor Vehicle Safety Standard No. 139.
Grades B and A represent higher levels of performance on the laboratory
test wheel than the minimum required by law.
Warning: The temperature grades for this tire are established for a tire that
is properly inflated and not overloaded.
Excessive speed, underinflation, or excessive loading, either separately or in
combination, can cause heat buildup and possible tire failure.
Glossary of tire terminology
Tire related termMeaning
Accessory weight
The combined weight (in excess of those standard
items which may be replaced) of automatic transmis-
sion, power steering, power brakes, power windows,
power seats, radio and heater, to the extent that these
items are available as factory-installed equipment
(whether installed or not)
Cold tire inflation pres-
sureTire pressure when the vehicle has been parked for
three hours or more, or has not been driven more
than 1 mile or 1.5 km under that condition
Curb weight
The weight of a motor vehicle with standard equip-
ment, including the maximum capacity of fuel, oil and
coolant, and if so equipped, air conditioning and
additional weight optional engine

588
6-2. Customization
IS250C/350C_U
Steering
wheel
(
→P. 76 )
Auto tilt-away functionOnOff
Power win-
dows
(
→P. 8 2 )
Wireless remote control
linked operationOffOn
Retractable
hardtop
(
→P. 9 0 )
Retractable hardtop
operation control linked
to the intuitive parking
assist
OnOff
Automatic
light control
system
(
→P. 1 76 )
Light sensor sensitivityLevel 3Level 1 to 5
Ti m e e l a p s e d b e f o r e
headlights automatically
turn off after doors are
closed
30 seconds
0 seconds
60 seconds
90 seconds
Lights
(
→P. 1 7 8 )
Daytime running light sys-
tem (U.S.A. only)OnOff
Windshield
wipers and
washer
(
→P. 1 8 2 )
Switching operation when
the vehicle is stationaryOnOff
Drip prevention functionOnOff
Ti m e e l a p s e d b e f o r e t h e
drip prevention function
operatesVa r i a b l e
depending on
the vehicle
speed
3 seconds
ItemFunctionDefault settingCustomizedsetting