brake LEXUS RX450h 2015 Workshop Manual

3032-5. Driving information
2
When driving
Selecting tire chains
Use the correct tire chain size when mounting the tire chains. Chain size
is regulated for each tire size.
Side chain:
0.12 in. (3 mm) in diameter
0.98 in. (25 mm) in length
0.43 in. (10.8 mm) in width
Cross chain:
0.15 in. (3.9 mm) in diameter
1.00 in. (25.3 mm) in length
0.54 in. (13.8 mm) in width
Regulations on the use of tire chains
Regulations regarding the use of tire chains vary depending on location
and type of road. Always check local regulations before installing chains. ■ When driving the vehicle
Accelerate the vehicle slowly, keep a safe distance between you and
the vehicle ahead, and drive at a reduced speed suitable to road
conditions.
■ When parking the vehicle
Park the vehicle and move the shif t lever to P without setting the
parking brake. The parking brake may freeze up, preventing it from
being released. If necessary, bl ock the wheels to prevent inadvert-
ent sliding or creeping.

3062-5. Driving information
Trailer towing (AWD models with towing package)
Towing related terms
■ GCWR (Gross Combination Weight Rating)
The maximum allowable gross
combination weight. The gross
combination weight is the sum of
the total vehicle weight (including
the occupants, cargo and any
optional equipment installed on
the vehicle) and the weight of the
trailer being towed (including the
cargo in the trailer).Your vehicle is designed primarily as a passenger-and-load-carrying vehi-
cle. Towing a trailer can have an adverse impact on handling, performance,
braking, durability, and fuel consumpt ion. For your safety and the safety of
others, you must not overload your vehicle or trailer. You must also ensure
that you are using appropriate towing equipment, that the towing equip-
ment has been installed correctly and used properly, and that you employ
the requisite driving habits.
Vehicle-trailer stability and braking performance are affected by trailer
stability, brake performance and settin g, trailer brakes, the hitch and hitch
systems (if equipped).
To tow a trailer safely, use extreme care and drive the vehicle in accor-
dance with your trailer’s characteristics and operating conditions.
Lexus warranties do not apply to damage or malfunction caused by towing
a trailer for commercial purposes.
Contact your Lexus dealer for furt her information about additional
requirements such as towing kits, etc.

3082-5. Driving information
■ TWR (Trailer Weight Rating)
The maximum allowable gross
trailer weight. The gross trailer
weight is the sum of the trailer
weight and the weight of the cargo
in the trailer.
TWR is calculated assuming base
vehicle with one driver, one front
passenger, towing package (if
available), hitch and hitch systems
(if required). Additional optional equipment,
passengers and cargo in the vehi-
cle will reduce the trailer weight
rating so as not to exceed GCWR,
GVWR and GAWR.
If the gross trailer weight exceeds
3000 lb. (1360 kg), it is recom-
mended to use a trailer with 2 or
more axles.
■ Unbraked TWR (Unbraked Trailer Weight Rating)
The trailer weight rating for towing
a trailer without a trailer service
brake system.(With brakes)
(Without brakes)

3092-5. Driving information
2
When driving ■ Tongue Weight
The load placed on the trailer hitch
ball. (  P. 311)
Weight limits
● The gross trailer weight must neve r exceed the TWR described in the
table. (  P. 310)
● The gross combination weight must never exceed the GCWR
described in the table. (  P. 310)
● The gross vehicle weight must
never exceed the GVWR indi-
cated on the Certification Label.
● The gross axle weight on each
axle must never exceed the
GAWR indicated on the Certifi-
cation Label.
● If the gross trailer weight is over the unbraked TWR, trailer service
brakes are required.
● If the gross trailer weight is over 2000 lb. (907 kg), a sway control
device with sufficient capacity is required.

3102-5. Driving information
GCWR, TWR, Unbraked TWR, Fifth wheel and Gooseneck towing TWR
Confirm that the gross trailer weight , gross combination weight, gross
vehicle weight, gross axle weight and tongue weight are all within the lim-
its.
■ GCWR
* and TWR
*
■ Unbraked TWR
*1000 lb. (453 kg)
* : These models meet the tow-vehicle trailering requirement of SAE Interna-
tional per SAE J2807. To w i n g t y p e Driving system GCWR TWR
With towing package AW D 9480 lb.
(4297 kg) 3500 lb.
(1588 kg)

3152-5. Driving information
2
When driving ■
Auto current cut-off function
In case of over current, the auto cut-off function stops the power flowing to the
trailer lights to prevent damage to the vehicle’s electrical system.
This function is activated when the rated current of any of the following trailer light
circuit components is exceeded: ●
Tail lights: maximum 7.8 A ●
Stop/turn signal light (right): maximum 4.5 A●
Stop/turn signal light (left): maximum 4.5 A■
When the auto current cut function is activated
If a trailer light does not come on due to the activation of the auto current cut func-
tion, the light system will need to be reset.
Follow the reset procedure shown below. ●
If a tail light does not come on, turn off the headlight switch.●
If the right-side stop/turn signal light does not come on, put the turn signal in the
off position or remove foot from the brake pedal.●
If the left-side stop/turn signal light does not come on, put the turn signal in the
off position or remove foot from the brake pedal.
If the emergency flashers do not operate, press the emergency flasher switch to
turn them off.
After the light system is reset, operate the light switches again to see if the lights
operate normally.
If the lights do not operate normally, have the vehicle inspected by your Lexus
dealer.

3172-5. Driving information
2
When driving ● Avoid jerky steering and sharp turns, and slow down before making a
turn.
● Note that when making a turn, the tr ailer wheels will be closer than the
vehicle wheels to the inside of th e turn. Compensate by making a
wider than normal turning radius.
● Slow down before making a turn, in cross winds, on wet or slippery sur-
faces, etc.
Increasing vehicle speed can destabilize the trailer.
● Take care when passing other vehi cles. Passing requires considerable
distance. After passing a vehicle, do not forget the length of your
trailer, and be sure you have plenty of room before changing lanes.
● To maintain engine braking efficiency and charging system perfor-
mance when using engine braking, do not put the transmission in D.
● Instability happens more frequently when descending steep or long
downhill grades. Before descending, slow down and downshift. Do not
make sudden downshifts while descending steep or long downhill
grades.
● Avoid holding the brake pedal down too long or applying the brakes
too frequently. This could cause th e brakes to overheat and result in
reduced braking efficiency.
● Due to the added load of the trailer, your vehicle’s engine may overheat
on hot days (at temperatures over 85°F [30°C]) when driving up a
long or steep grade. If the eng ine coolant temperature gauge indicates
overheating, immediately turn off th e air conditioning (if in use), pull
your vehicle off the road and stop in a safe spot. (  P. 7 8 8 )

3182-5. Driving information
● Always place wheel bloc ks under both the vehi cle’s and the trailer’s
wheels when parking. Apply the pa rking brake firmly, and put the
transmission in P. Avoid parking on a slope, but if unavoidable, do so
only after performing the following:
Apply the brakes and keep them applied.
Have someone place wheel blocks under both the vehicle’s and
trailer’s wheels.
When the wheel blocks are in pl ace, release the brakes slowly
until the blocks absorb the load.
Apply the parking brake firmly.
Shift into P and turn off the hybrid system.
● When restarting after parking on a slope:
With the transmission in P, start the hybrid system. Be sure to
keep the brake pedal depressed.
Shift into a forward gear. If reversing, shift into R.
Release the parking brake and br ake pedal, and slowly pull or
back away from the wheel blocks. Stop and apply the brakes.
Have someone retrieve the blocks.STEP 1
STEP 2
STEP 3
STEP 4
STEP 5
STEP 1
STEP 2
STEP 3
STEP 4

3202-5. Driving information
■
Break-in schedule
If your vehicle is new or equipped with any new power train components (such as
an engine, transmission, differential or wheel bearing), Lexus recommends that you
do not tow a trailer until the vehicle has been driven for over 500 miles (800 km).
After the vehicle has been driven for over 500 miles (800 km), you can start tow-
ing. However, for the next 500 miles (800 km), drive the vehicle at a speed of less
than 50 mph (80 km/h) when towing a trailer, and avoid full throttle acceleration.■
Maintenance ●
If you tow a trailer, your vehicle will require more frequent maintenance due to
the additional load. (See “Warranty and Services Guide”, “Owner's Manual
Supplement” or “Scheduled Maintenance”.)●
Retighten the fixing bolts of the towing ball and bracket after approximately
600 miles (1000 km) of trailer towing.■
If trailer sway occurs
One or more factors (crosswinds, passing vehicles, rough roads, etc.) can adversely
affect handling of your vehicle and trailer, causing instability. ●
If trailer swaying occurs:
• Firmly grip the steering wheel. Steer straight ahead.
Do not try to control trailer sway ing by turning the steering wheel.
• Begin releasing the accelerator peda l immediately but very gradually to
reduce speed.
Do not increase speed. Do not apply vehicle brakes.
If you make no extreme correction with the steering or brakes, your vehicle and
trailer should stabilize. ●
After the trailer swaying has stopped:
• Stop in a safe place. Get all occupants out of the vehicle.
• Check the tires of the vehicle and the trailer.
• Check the load in the trailer.
Make sure the load has not shifted.
Make sure the tongue weight is appropriate, if possible.
• Check the load in the vehicle.
Make sure the vehicle is not ov erloaded after occupants get in.
If you cannot find any problems, the speed at which trailer swaying occurred is
beyond the limit of your particular vehicle-trailer combination.
Drive at a lower speed to prevent instability. Remember that swaying of the towing
vehicle-trailer increases as speed increases.

3212-5. Driving information
2
When driving CAUTION■
Trailer towing precautions
To tow a trailer safely, use extreme care an d drive the vehicle in accordance with the
trailer’s characteristics and operating conditions. Failure to do so could cause an
accident resulting in death or serious injury. Vehicle stability and braking perfor-
mance are affected by trailer stability, brake setting and performance, and the hitch.
Your vehicle will handle differently when towing a trailer.■
To avoid accident or injury ●
Do not exceed the TWR, unbraked TWR, GCWR, GVWR or GAWR.●
If the gross trailer weight is over 2000 lb. (907 kg), a sway control device with
sufficient capacity is required.●
Adjust the tongue weight within the appropriate range. Place heavier loads as
close to the trailer axle as possible.●
Do not exceed 65 mph (104 km/h), the posted towing speed limit or the speed
limit for your trailer as set forth in your trailer owner’s manual, whichever is lowest.
Slow down sufficiently before making a turn, in cross winds, on wet or slippery
surface, etc. to help avoid an accident. If you experience a vehicle-trailer instabil-
ity from reducing a certain speed, slow down and make sure you keep your vehi-
cle speed under the speed of which you experience the instability.●
Do not make jerky, abrupt or sharp turns.●
Do not apply the brakes suddenly as you may skid, resulting in jackknifing and
loss of vehicle control. This is especially true on wet or slippery surfaces.●
Do not exceed the trailer hitch assembly weight, gross vehicle weight, gross axle
weight and trailer tongue weight capacities.●
Do not use cruise control when towing.●
Slow down and downshift before descending steep or long downhill grades. Do
not make sudden downshifts while descending steep or long downhill grades.
●
Vehicle-trailer instability is more likely on steep long downhills. Before descend-
ing steep or long downhill grades, slow down and downshift. Do not make sudden
downshifts when descending steep or lo ng downhill grades. Avoid holding the
brake pedal down too long or applying the brakes too frequently. This could
cause the brakes to overheat and result in reduced braking efficiency.
●
Do not tow a trailer when the compact spare tire is installed on your vehicle.