2012 Lexus HS250h snow chains

235
2-4. Using other driving systems
2
When driving
HS250h_U_75050U
CAUTION
■Before using the LKA system
Do not rely on the LKA system to remain within a selected lane. The LKA system is
not designed to enable inattentive driving. The steering wheel should be operated
by the driver to maintain the vehicle in a suitable position within its lane. Always
drive carefully.
■Turn the LKA off while driving in any of the following conditions:
Do not use LKA in any of the following situations.
Otherwise, the system may not function correctly and could result in an accident.
●When driving with snow tires, tire chains, a spare tire, or similar equipment.
●When driving with non-standard parts or aftermarket equipment installed.
(including modified tires and suspensions, etc.)
●When towing a trailer.
●When there are objects or structures along the roadside that might be misinter-
preted as lane markers. (such as guardrails, curb, reflector posts, etc.)
●When there are wheel ruts, icy trademarks, etc. or if snow remains on the road
surface.
●When there are shadows on the road running parallel with lane markers, or if a
shadow covers the lane markers.
●When there are visible lines on the pavement from road repairs, or if the remains
of old lane markers are still visible on the road.
●When driving on slippery roads, such as those covered with rain, ice or snow.
●When driving in a lane other than the driving or passing lanes on a freeway or
highway.
●When driving on a road with lane closures due to maintenance, or when driving
in a temporary lane.
●When driving on winding roads or roads that are rough or uneven.

241
2-4. Using other driving systems
2
When driving
HS250h_U_75050U
■Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the system from over-
heating 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.
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 normal condi-
tions
The ABS is not designed to shorten the vehicle’s stopping distance. Always main-
tain a safe distance from the vehicle in front of you in the following situations:
●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 roads with uneven surfaces
■TRAC may not operate effectively when
Directional control and power may not be achievable while driving on slippery 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.
■When the TRAC/VSC systems are turned off
Be especially careful and drive at a speed appropriate to the road conditions. As
these are the systems to ensure vehicle stability and driving force, do not turn the
TRAC/VSC systems off unless necessary.

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2-5. Driving information
HS250h_U_75050U
Winter driving tips
Carry out the necessary preparations and inspections before driving the
vehicle in winter. Always drive the vehicle in a manner appropriate to the
prevailing weather conditions.
■Pre-winter preparations
●Use fluids that are appropriate to the prevailing outside tempera-
tures.
• Engine oil
• Engine/power control unit coolant
• Washer fluid
● Have the vehicle fitted with four snow tires or purchase a set of
tire chains for the front tires.
Ensure that all tires are the same size and brand, and that chains match
the size of the tires.
■ Before driving the vehicle
Perform the following according to the driving conditions:
●Do not try to forcibly open a window or move a wiper that is fro-
zen. Pour warm water over the frozen area to melt the ice. Wipe
away the water immediately to prevent it from freezing.
● To ensure proper operation of the climate control system fan,
remove any snow that has accumulated on the air inlet vents in
front of the windshield.
● Remove any ice that has accumulated on the vehicle chassis.
● Periodically check for and remove any excess ice or snow that
may have accumulated in the wheel well or on the brakes.
■ When driving the vehicle
Accelerate the vehicle slowly and drive at a reduced speed suitable to the
road conditions.

260
2-5. Driving information
HS250h_U_75050U
CAUTION
■Driving with snow tires
Observe the following precautions to reduce the risk of accidents.
Failure to do so may result in a loss of vehicle control and cause death or serious
injury.
●Use tires of the size specified.
●Maintain the recommended level of air pressure.
●Do not drive in excess of 75 mph (120 km/h), regardless of the type of snow tires
being used.
●Use snow tires on all, not just some wheels.
■Driving with tire chains
Observe the following precautions to reduce the risk of accidents.
Failure to do so may result in the vehicle being unable to be driven safely, and may
cause death or serious injury.
●Do not drive in excess of the speed limit specified for the tire chains being used,
or 30 mph (50 km/h), whichever is lower.
●Avoid driving on bumpy road surfaces or over potholes.
●Avoid sudden acceleration, deceleration and braking, as well as sharp cornering.
●Slow down sufficiently before entering a curve to ensure that vehicle control is
maintained.
NOTICE
■Repairing or replacing snow tires
Request repairs or replacement of snow tires from Lexus dealers or legitimate tire
retailers.
This is because the removal and attachment of snow tires affects the operation of
the tire pressure warning valves and transmitters.
■Fitting tire chains
The tire pressure warning valves and transmitters may not function correctly when
tire chains are fitted.

454
4-3. Do-it-yourself maintenance
HS250h_U_75050U
■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 cannot be properly repaired due to the size or
location of a cut or other damage.
If you are not sure, consult with your Lexus dealer.
■Replacing tires and wheels
If the ID code of the tire pressure warning valve and transmitter is not registered,
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 lif e
Any tire over 6 years old must be checked by a qualified technician even if it has sel-
dom 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 pressure
checks. Make sure to check tire inflation pressure as part of your routine of daily
vehicle checks.
■Low profile tires (vehicles with P225/45R18 91W tires)
Generally, low profile tires will wear more rapidly and tire grip performance 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.

508
5-2. Steps to take in an emergency
HS250h_U_75050U
■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 inflation pressure changes caused by temperature. In this case,
adjusting the tire inflation pressure will turn off the warning light (after a few min-
utes).
■When a tire is replaced with a spare tire
The compact spare tire is not equipped with a tire pressure warning valve and trans-
mitter. 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
repaired tire and adjust the tire inflation pressure. The tire pressure warning light
will go off after a few minutes.
■If the tire pressure warning system is not functioning
The tire pressure warning system will be disabled in the following conditions:
(When the condition becomes normal, the system will work properly.)
●If tires not equipped with tire pressure warning valves and transmitters are used.
●If the ID code on the tire pressure warning valves and transmitters is not regis-
tered in the tire pressure warning computer.
●If the tire inflation pressure is 73 psi (500 kPa, 5.1 kgf/cm2 or bar) or higher.
The tire pressure warning system may be disabled in the following conditions:
(When the condition becomes normal, the system will work properly.)
●If electronic devices or facilities using similar radio wave frequencies are nearby.
●If a radio set at similar frequency is in use in the vehicle.
●If a window tint that affects the radio wave signals is installed.
●If there is a lot of snow or ice on the vehicle, particularly around the wheels or
wheel housings.
●If non-genuine Lexus wheels are used (Even if you use Lexus wheels, the tire
pressure warning system may not work properly with some types of tires.)
●If tire chains are used.

5
When trouble arises
537
5-2. Steps to take in an emergency
HS250h_U_75050UFirmly tighten each wheel nut two
or three times in the order shown
in the illustration.
Tightening torque:
76 ft•lbf (103 N•m, 10.5 kgf•m)
Stow the flat tire, tire jack and all tools.
■The compact spare tire
●The compact spare tire is identified by the label “TEMPORARY USE ONLY”
on the tire sidewall.
Use the compact spare tire temporarily, and only in an emergency.
●Make sure to check the tire inflation pressure of the compact spare tire.
(
→ P. 5 6 7 )
■After completing the tire change
The tire pressure warning system must be reset. ( →P. 4 5 3 )
■When using the compact spare tire
As the compact spare tire is not equipped with a tire pressure warning valve and
transmitter, low inflation pressure of the spare tire will not be indicated by the tire
pressure warning system. Also, if you replace the compact spare tire after the tire
pressure warning light comes on, the light remains on.
■If you have a flat front tire on a road covered with snow or ice
Install the compact spare tire on one of the rear wheels of the vehicle. Perform the
following steps and fit tire chains to the front tires:
Replace a rear tire with the compact spare tire.
Replace the flat front tire with the tire removed from the rear of the vehi-
cle.
Fit tire chains to the front tires.

622
Alphabetical index
HS250h_U_75050U
Fog light switch................................... 202
Ignition switch........................................152
Light switches ......................................... 191
Mode select switch............................. 162
Power door lock switch ...................... 61
Power switch ......................................... 152
Power window switch ........................ 90
Talk switch................................328, 347
Telephone switch .............................. 347
Tire pressure warning reset switch ................................................... 453
Window lock switch ........................... 90
Wiper and washer switch ............. 204
Tail lights Replacing light bulbs..........................491
Switch ......................................................... 191
Wattage................................................. 568
Talk switch* ................................. 328, 347
Telephone switch*................................ 347
Theft deterrent system Alarm ........................................................ 103
Immobilizer system.............................. 101
Theft prevention labels ........................ 106
TILT switch*
Tire inflation pressure .........................459
Tire information Glossary.................................................578
Size ........................................................... 575
Tire identification number ............. 574
Uniform Tire Quality Grading.... 576
Tires
Chains ..................................................... 259
Checking .................................................451
Compact spare tire .......................... 532
If you have a flat tire .......................... 532 Inflation pressure ............................... 459
Inflation pressure sensor ............... 452
Information ............................................572
Replacing .............................................. 532
Rotating tires.......................................... 451
Size ........................................................... 567
Snow tires.............................................. 258
Spare tire ............................................... 532
Tire pressure warning
system....................................... 451, 505
Tools........................................................... 532
Total load capacity ............................... 257
Towing Dinghy towing .....................................262
Emergency towing ........................... 495
Trailer towing ........................................ 261
TRAC ........................................................ 238
Traction control..................................... 238
Trailer towing ...........................................261
Trip meter ..................................................169
Trunk Opener ......................................................64
Turn signal lights Replacing light bulbs ......................... 481
Switch ........................................................ 166
Wattage .................................................568
Vanity lights Vanity lights.......................................... 386
Wattage .................................................568
Vanity mirrors ........................................ 386
Vehicle identification number ......... 560
Vehicle stability control ..................... 238
Ventilators ...............................................389
VIEW button*
VSC ........................................................... 238
T
V