towing Lexus GS300h 2015 User Guide

2134-1. Before driving
4
Driving
GS450h_300h_OM_OM30F00E_(EE)
■Tire information
●Increase the tire inflation pressure to 20.0 kPa (0.2 kgf/cm2 or bar, 3 psi) greater than
the recommended value when towing. ( →P. 5 7 5 )
●Increase the air pressure of the trailer tires in accordance with the total trailer weight
and according to the values recommended by the manufacturer of your trailer.
■Trailer lights
●Please consult at any authorized dealer or repairer, or another duly qualified and
equipped professional when in stalling trailer lights, as incorrect installation may cause
damage to the vehicle’s lights. Please take care to comply with your state’s laws when
installing trailer lights.
●Check that the turn signal lights and stoplights are operating correctly every time you
hitch up the trailer. Directly wiring up to your vehicle may damage the electrical system
and stop the lights from functioning correctly.
■Break-in schedule
Lexus recommends that vehicles fitted with new power train components should not be
used for towing trailers for the first 800 km (500 miles).
■Safety checks before towing
●Check that the maximum load limit for the towing hitch/bracket and hitch ball is not
exceeded. Bear in mind that the coupling weight of the trailer will add to the load
exerted on the vehicle. Also make sure that the total load exerted on the vehicle is
within the range of the weight limits. ( →P. 2 1 1 )
●Ensure that the trailer load is secure.
●Supplementary outside rear view mirrors shou ld be added to the vehicle if the traffic
behind cannot be clearly seen with standa rd mirrors. Adjust the extending arms of
these mirrors on both sides of the vehicle so that they always provide maximum visibility
of the road behind.
■Maintenance
●Maintenance must be performed more frequently when using the vehicle for towing
due to the greater weight burden placed on the vehicle compared to normal driving.
●Retighten all bolts securing the hitching ball and bracket after towing for approximately
1000 km (600 miles).
NOTICE
■When the rear bumper strengthening material is aluminum
Ensure the steel bracket part does not come directly in contact with that area.
When steel and aluminum come into contact, there is a reaction similar to corrosion,
which will weaken the section concerned and may result in damage. Apply a rust inhib-
itor to parts that will come in co ntact when attaching a steel bracket.

2144-1. Before driving
GS450h_300h_OM_OM30F00E_(EE)
Your vehicle will handle differently when towing a trailer. In order to avoid acci-
dent, death or serious injury, keep the following in mind when towing:
■Checking connections between trailer and lights
Stop the vehicle and check the operation of the connection between the
trailer and lights after driving for a brief period as well as before starting off.
■Practicing driving with a coupled trailer
●Get the feel for turning, stopping and reversing with the trailer coupled by
practicing in an area with no or light traffic.
●When reversing with a coupled trailer, hold the section of the steering
wheel nearest to you and rotate clockwise to turn the trailer left or counter-
clockwise to turn it right. Always rotate a little at a time to prevent steering
error. Have someone guide you when reversing to lessen the risk of an
accident.
■Increasing vehicle-to-vehicle distance
At a speed of 10 km/h (6 mph), the distance to the vehicle running ahead of
you should be equivalent to or greater than the combined length of your vehi-
cle and trailer. Avoid sudden braking th at may cause skidding. Otherwise, the
vehicle may spin out of control. This is especially true when driving on wet or
slippery road surfaces.
■Sudden acceleration/steering input/cornering
Executing sharp turns when towing may result in the trailer colliding with your
vehicle. Decelerate well in advance when approaching turns and take them
slowly and carefully to avoid sudden braking.
■Important points regarding turning
The wheels of the trailer will travel closer to the inside of the curve than the
wheels of the vehicle. To make allowance for this, take the turns wider than you
would normally do.
■Important points regarding stability
Vehicle movement resulting from uneven road surfaces and strong cross-
winds will affect handling. The vehicle may also be rocked by passing buses or
large trucks. Frequently check behind when moving alongside such vehicles.
As soon as such vehicle movement occurs, immediately start to decelerate
smoothly by slowly applying the brakes. Always steer the vehicle straight
ahead while braking.
Guidance

2154-1. Before driving
4
Driving
GS450h_300h_OM_OM30F00E_(EE)
■Passing other vehicles
Consider the total combined length of your vehicle and trailer and ensure that
the vehicle-to-vehicle distance is sufficient before executing lane changes.
■Transmission information
To maintain engine braking efficiency, when using engine braking, when driv-
ing on a long steep downgrade, do not use the transmission in D. ( →P. 2 2 7 )
■If the engine overheats
Towing a loaded trailer up a long, steep incline in temperatures exceeding
30 °C (85 °F) may result in the engine overheating. If the engine coolant tem-
perature gauge indicates that the engine is overheating, turn the air condition-
ing off immediately, leave the road and stop the vehicle in a safe place.
( → P. 5 5 6 )
■When parking the vehicle
Always place wheel chocks under the whee ls of both the vehicle and trailer.
Firmly set the parking brake and shift the shift lever to P.
WA R N I N G
Follow all the instructions described in this section. Failure to do so could cause an acci-
dent resulting in death or serious injury.
■Trailer towing precautions
When towing, make sure that none of the weight limits are exceeded. ( →P. 211)
■To avoid accident or injury
●Do not tow a trailer when the compact spare tire is installed on your vehicle.
●Do not tow a trailer when the tire installed is repaired with the emergency tire punc-
ture repair kit.
●Do not use cruise control (if equipped), dynamic radar cruise control (if equipped) or
dynamic radar cruise control with full-speed range (if equipped) when trailer towing.
■Vehicle speed in towing
Observe the legal maximum speeds for trailer towing.
■Before descending hills or long declines
Reduce speed and downshift. However, never downshift suddenly while descending
steep or long downhill grades.
■Operation of the brake pedal
Do not hold the brake pedal depressed often or for long periods of time.
Doing so may result in the brake overheating or reduce braking effects.

2324-2. Driving procedures
GS450h_300h_OM_OM30F00E_(EE)
■Parking brake operation
●When the power switch is not in ON mode, the parking brake cannot be released using
the parking brake switch.
●When the power switch is not in ON mode, automatic mode (automatic brake setting
and releasing) is not available.
●If the parking brake is operated repeatedly over a short period of time, the system may
restrict operation to prevent overheating. If this happens, refrain from operating the
parking brake. Normal operation will return after about 1 minute.
●Vehicles with towing package: In situations such as when parking while towing a trailer,
the maximum amount of braking force can be used by pressing the parking brake
switch with the parking brake already set.
●Vehicles without towing package: In situations such as when parking on a steep slope*,
the maximum amount of braking force can be used by pressing the parking brake
switch with the parking brake already set.
*: Use wheel chocks when parking on a steep slope.
■Parking brake operation sound
When the parking brake operates, a motor sound (whirring sound) may be heard. This
does not indicate a malfunction.
■Parking brake indicator light
●Depending on the power switch mode, the parking brake indicator light will come on
and stay on as described below:
ON mode: Comes on until the parking brake is released.
Not in ON mode: Stays on for approximately 15 seconds.
●When the power switch is turned off with the parking brake set, the parking brake indi-
cator light will stay on for about 15 seco nds. This does not indicate a malfunction.
■When there is a malfunction in the system
Warning lights and/or warning message will turn on or flash. (→P. 4 7 8 , 4 8 2 )
Depending on the condition, the park ing brake indicator light may flash.
■Parking brake engaged warning buzzer
→P. 4 8 8
■Usage in winter time
→P. 3 5 4

2714-5. Using the driving support systems
4
Driving
GS450h_300h_OM_OM30F00E_(EE)
WA R N I N G
■Pre-crash braking*3
●The pre-crash braking function may not operate if certain operations are performed
by the driver. If the accelerator pedal is being depressed strongly or the steering
wheel is being turned, the system may determine that the driver is taking evasive
action and possibly prevent the pre-crash braking function from operating.
●In some situations, while the pre-crash braking function is operating, operation of the
function may be canceled if the accelerator pedal is depressed strongly or the steer-
ing wheel is turned and the system determines that the driver is taking evasive action.
●A large amount of braking force is applied while the pre-crash braking function is
operating. As the pre-crash braking function will be canceled after the vehicle has
been stopped for approximately 2 seconds, the driver should depress the brake
pedal as necessary.
●If the brake pedal is being depressed, the system may determine that the driver is tak-
ing evasive action and possibly delay the operation timing of the pre-crash braking
function.
*3: Depending on the region in which the vehicle was sold, the pre-crash braking func-
tion may not be available.
■When to disable the pre-crash safety system
In the following situations, disable the system, as it may not operate properly, possibly
leading to an accident resulting in death or serious injury:
●When the vehicle is being towed
●When your vehicle is towing another vehicle
●When transporting the vehicle via truck, boat, train or similar means of transportation
●When the vehicle is raised on a lift with the hybrid system operating and the tires are
allowed to rotate freely
●When inspecting the vehicle using a drum tester such as a chassis dynamometer or
speedometer tester, or when using an on vehicle wheel balancer
●When a strong impact is applied to the front bumper or front grille, due to an accident
or other reasons
●If the vehicle cannot be driven in a stable manner, such as when the vehicle has been
in an accident or is malfunctioning
●When the vehicle is driven in a sporty manner or off-road
●When the tires are not properly inflated
●When the tires are very worn
●When tires of a size other than specified are installed
●When tire chains are installed
●When a compact spare tire or an emergency tire puncture repair kit is used

2844-5. Using the driving support systems
GS450h_300h_OM_OM30F00E_(EE)
WA R N I N G
■Before using LKA system
Do not rely solely upon the LKA system. LKA is not a system which automatically
drives the vehicle or reduces the amount of attention that must be paid to the area in
front of the vehicle. The driver must always assume full responsibility for driving safely
by always paying careful attention to the surrounding conditions and operate the steer-
ing wheel to correct the path of the vehicle. Also, make sure to take adequate breaks
when fatigued, such as from driving for a long period of time.
Failure to perform appropriate driving operations and pay careful attention may lead to
an accident, resulting in death or serious injury.
■To avoid operating LKA by mistake
When not using the LKA system, use the LKA switch to turn the system off.
■Situations unsuitable for LKA
Do not use the LKA system in the following situations.
The system may not operate properly and lead to an accident, resulting in death or
serious injury.
●A spare tire, tire chains, etc., are equipped.
●When the tires have been excessively worn, or when the tire inflation pressure is low.
●Tires which differ by structure, manufacturer, brand or tread pattern are used.
●Objects or patterns that could be mistaken for white (yellow) lines are present on the
side of the road (guardrails, curbs, reflective poles, etc.).
●Vehicle is driven on a snow-covered road.
●White (yellow) lines are difficult to see due to rain, snow, fog, dust, etc.
●Asphalt repair marks, white (yellow) line ma rks, etc., are present due to road repair.
●Vehicle is driven in a temporary lane or restricted lane due to construction work.
●Vehicle is driven on a road surface which is slippery due to rainy weather, fallen snow,
freezing, etc.
●Vehicle is driven in traffic lanes other than on highways and freeways.
●Vehicle is driven in a construction zone.
●Vehicle is towing a trailer or another vehicle.
■Preventing LKA system malfunctions and operations performed by mistake
●Do not modify the headlights or place stickers, etc., on the surface of the lights.
●Do not modify the suspension etc. If the suspension etc. needs to be replaced, con-
tact any authorized Lexus dealer or repair er, or another duly qualified and equipped
professional.
●Do not install or place anything on the hood or grille. Also, do not install a grille guard
(bull bars, kangaroo bar, etc.).
●If your windshield needs repairs, contact any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.

2924-5. Using the driving support systems
GS450h_300h_OM_OM30F00E_(EE)
WA R N I N G
■Before using LDA system
Do not rely solely upon the LDA system. LDA is not a system which automatically
drives the vehicle or reduces the amount of attention that must be paid to the area in
front of the vehicle. The driver must always assume full responsibility for driving safely
by always paying careful attention to the surrounding conditions and operate the steer-
ing wheel to correct the path of the vehicle. Also, make sure to take adequate breaks
when fatigued, such as from driving for a long period of time.
Failure to perform appropriate driving operations and pay careful attention may lead to
an accident, resulting in death or serious injury.
■To avoid operating LDA by mistake
When not using the LDA system, use the LDA switch to turn the system off.
■Situations unsuitable for LDA
Do not use the LDA system in the following situations.
The system may not operate properly and lead to an accident, resulting in death or
serious injury.
●A spare tire, tire chains, etc., are equipped.
●When the tires have been excessively worn, or when the tire inflation pressure is low.
●Tires which differ by structure, manufacturer, brand or tread pattern are used.
●Objects or patterns that could be mistaken for white (yellow) lines are present on the
side of the road (guardrails, curbs, reflective poles, etc.).
●Vehicle is driven on a snow-covered road.
●White (yellow) lines are difficult to see due to rain, snow, fog, dust, etc.
●Asphalt repair marks, white (yellow) line ma rks, etc., are present due to road repair.
●Vehicle is driven in a temporary lane or restricted lane due to construction work.
●Vehicle is driven on a road surface which is slippery due to rainy weather, fallen snow,
freezing, etc.
●Vehicle is driven in traffic lanes other than on highways and freeways.
●Vehicle is driven in a construction zone.
●Vehicle is towing a trailer or another vehicle.
■Preventing LDA system malfunctions and operations performed by mistake
●Do not modify the headlights or place stickers, etc., on the surface of the lights.
●Do not modify the suspension etc. If the suspension etc. needs to be replaced, con-
tact any authorized Lexus dealer or repair er, or another duly qualified and equipped
professional.
●Do not install or place anything on the hood or grille. Also, do not install a grille guard
(bull bars, kangaroo bar, etc.).
●If your windshield needs repairs, contact any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.

3054-5. Using the driving support systems
4
Driving
GS450h_300h_OM_OM30F00E_(EE)
WA R N I N G
■Situations unsuitable for dynamic radar cruise control with full-speed range
Do not use dynamic radar cruise control with full-speed range in any of the following
situations.
Doing so may result in inappropriate speed control and could cause an accident result-
ing in death or serious injury.
●Roads where there are pedestrians, cyclists, etc.
●In heavy traffic
●On roads with sharp bends
●On winding roads
●On slippery roads, such as those covered with rain, ice or snow
●On steep downhills, or where there are sudden changes between sharp up and down
gradients
Vehicle speed may exceed the set speed when driving down a steep hill.
●At entrances to freeways and highways
●When weather conditions are bad enough that they may prevent the sensors from
detecting correctly (fog, snow, sandstorm, heavy rain, etc.)
●When there is rain, snow, etc. on the front surface of the radar sensor or camera sen-
sor
●In traffic conditions that require frequent repeated acceleration and deceleration
●When your vehicle is towing a trailer or during emergency towing
●When an approach warning buzzer is heard often

3174-5. Using the driving support systems
4
Driving
GS450h_300h_OM_OM30F00E_(EE)
WA R N I N G
■Situations unsuitable for dynamic radar cruise control
Do not use dynamic radar cruise control in any of the following situations.
Doing so may result in inappropriate speed control and could cause an accident result-
ing in death or serious injury.
●Roads where there are pedestrians, cyclists, etc.
●In heavy traffic
●On roads with sharp bends
●On winding roads
●On slippery roads, such as those covered with rain, ice or snow
●On steep downhills, or where there are sudden changes between sharp up and down
gradients
Vehicle speed may exceed the set speed when driving down a steep hill.
●At entrances to freeways and highways
●When weather conditions are bad enough that they may prevent the sensors from
detecting correctly (fog, snow, sandstorm, heavy rain, etc.)
●When there is rain, snow, etc. on the front surface of the radar sensor or camera sen-
sor
●In traffic conditions that require frequent repeated acceleration and deceleration
●When your vehicle is towing a trailer or during emergency towing
●When an approach warning buzzer is heard often

3294-5. Using the driving support systems
4
Driving
GS450h_300h_OM_OM30F00E_(EE)
■Automatic cruise control cancelation
Cruise control will stop maintaining the vehicle speed in any of the following situations.
●Actual vehicle speed falls more than approximately 16 km/h (10 mph) below the preset
vehicle speed.
At this time, the memorized set speed is not retained.
●Actual vehicle speed is below approximately 40 km/h (25 mph).
●VSC is activated.
●TRC is activated for a period of time.
●When the VSC or TRC system is turned off by pressing the VSC OFF switch.
■If the warning message for the cruise control is shown on the multi-information display
Press the “ON/OFF” button once to deactivate the system, and then press the button
again to reactivate the system.
If the cruise control speed cannot be set or if the cruise control cancels immediately after
being activated, there may be a malfunction in the cruise control system. Have the vehi-
cle inspected by any authorized Lexus dealer or repairer, or another duly qualified and
equipped professional.
WA R N I N G
■To avoid operating the cruise control by mistake
Switch the cruise control off using the “ON/OFF” button when not in use.
■Situations unsuitable for cruise control
Do not use cruise control in any of the following situations.
Doing so may result in loss of control and could cause an accident resulting in death or
serious injury.
●In heavy traffic
●On roads with sharp bends
●On winding roads
●On slippery roads, such as those covered with rain, ice or snow
●On steep hills
Vehicle speed may exceed the set sp eed when driving down a steep hill.
●When your vehicle is towing a trailer or during emergency towing