towing LEXUS GS300H 2019 User Guide

2134-1. Before driving
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Driving
GS450h_300h_OM_OM30F92E_(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. 555)
●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 any authorized Lexus retailer or Lexus authorized repairer, or any reli-
able repairer when installing trailer lights, as incorrect installation may cause damage to the vehicle’s lights. Please take care to comply with your state’s laws when installingtrailer lights.
●Check that the turn signal lights and stoplights are operating correctly every time youhitch up the trailer. Directly wiring up to your vehicle may damage the electrical systemand 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. 211)
●Ensure that the trailer load is secure.
●Supplementary outside rear view mirrors should be added to the vehicle if the traffic behind cannot be clearly seen with standard mirrors. Adjust the extending arms ofthese 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_OM30F92E_(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 an d 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 that 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
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Driving
GS450h_300h_OM_OM30F92E_(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. 227)
■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. 535)
■When parking the vehicle
Always place wheel chocks under the wheels of both the vehicle and trailer.
Firmly set the parking brake and shift the shift lever to P.
WARNING
Follow all the instructions described in this se ction. 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) 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 ov erheating or reduce braking effects.

2334-2. Driving procedures
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Driving
GS450h_300h_OM_OM30F92E_(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 wi ll 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 th e 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. 462, 466) Depending on the condition, the park ing brake indicator light may flash.
■Parking the vehicle
 P. 200
■Parking brake engaged warning buzzer
 P. 472
■Usage in winter time
 P. 334

2724-5. Using the driving support systems
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WARNING
■Pre-crash braking*3
●When the pre-crash braking function is operating, a large amount of braking force will be applied.
●If the vehicle is stopped by the operation of the pre-crash braking function, the pre-crash braking function operation will be canceled after approximately 2 seconds.Depress the brake pedal as necessary.
●The pre-crash braking function may not operate if certain operations are performedby the driver. If the accelerator pedal is being depressed strongly or the steeringwheel 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 thefunction 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.
●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 on and the tires are allowed to rotate freely
●When inspecting the vehicle using a drum tester such as a chassis dynamometer orspeedometer 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 beenin 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
●If equipment (snow plow, etc.) that may obstruct the radar sensor or camera sensor istemporarily installed to the vehicle

2854-5. Using the driving support systems
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Driving
GS450h_300h_OM_OM30F92E_(EE)
WARNING
■Before using LKA system
Do not rely solely upon the LKA system. Th e LKA system does not automatically drive the vehicle or reduce 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 pay- ing careful attention to the surrounding conditions and operating the steering wheel tocorrect the path of the vehicle. Also, the driver must take adequate breaks when
fatigued, such as from driving for a long period of time. Failure to perform appropriate driving operat ions and pay careful attention may lead to an accident, resulting in death or serious injury.
■To avoid operating LKA system by mistake
When not using the LKA system, use the LKA switch to turn the system off.
■Situations unsuitable for LKA system
Do not use the LKA system in the following situations. The system may not operate properly and le ad 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, cu rbs, 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 marks, 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. (vehicles with towing package)
■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 retailer or Le xus authorized repairer, or any reliable
repairer.
●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, contac t any authorized Lexus retailer or Lexus authorized repairer, or any reliable repairer.

2984-5. Using the driving support systems
GS450h_300h_OM_OM30F92E_(EE)
WARNING
■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 downgradients
Vehicle speed may exceed the set sp eed 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 fron t 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 (vehicles with towing package) or during emer-gency towing
●When an approach warning buzzer is heard often

3104-5. Using the driving support systems
GS450h_300h_OM_OM30F92E_(EE)
■Automatic cruise control cancelation
Cruise control will stop maintaining the vehicl e 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 retaile r or Lexus authorized repairer, or any reli-
able repairer.
WARNING
■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 orserious 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 hillsVehicle speed may exceed the set sp eed when driving down a steep hill.
●When your vehicle is towing a trailer or during emergency towing

3204-5. Using the driving support systems
GS450h_300h_OM_OM30F92E_(EE)
■The Blind Spot Monitor function is operational when
●The BSM function is turned on.
●Vehicle speed is greater than approximately 16 km/h (10 mph).
■The Blind Spot Monitor function will detect a vehicle when
●A vehicle in an adjacent lane overtakes your vehicle.
●Another vehicle enters the detection area when it changes lanes.
■Conditions under which the Blind Spot Monitor function will not detect a vehicle
The Blind Spot Monitor function is not designed to detect the following types of vehicles and/or objects:
●Small motorcycles, bicycles, pedestrians etc.*
●Vehicles traveling in the opposite direction
●Guardrails, walls, signs, parked vehi cles and similar stationary objects*
●Following vehicles that are in the same lane*
●Vehicles driving 2 lanes across from your vehicle*
*: Depending on conditions, detection of a vehicle and/or object may occur.
■Conditions under which the Blind Spot Monitor function may not function correctly
●The Blind Spot Monitor function may not detect vehicles correctly in the following con-
ditions:
• During bad weather such as heavy rain, fog, snow etc. • When ice or mud etc. is attached to the rear bumper
• When driving on a road surface that is wet due to rain, standing water etc. • When there is a significant difference in speed between your vehicle and the vehiclethat enters the detection area
• When a vehicle is in the detection area from a stop and remains in the detection area as your vehicle accelerates• When driving up or down consecutive steep inclines, such as hills, a dip in the road
etc. • When multiple vehicles approach with only a small gap between each vehicle• When vehicle lanes are wide, and the vehicle in the next lane is too far away from
your vehicle • When the vehicle that enters the detection area is traveling at about the same speedas your vehicle
• When there is a significant difference in height between your vehicle and the vehicle that enters the detection area• Directly after the BSM function is turned on
• When your vehicle is towing a tra iler (vehicles with towing package)
●Instances of the Blind Spot Monitor function unnecessarily detecting a vehicle and/ or object may increase under the following conditions:
• When there is only a short distance between your vehicle and a guardrail, wall etc.
• When there is only a short distance between your vehicle and a following vehicle • When vehicle lanes are narrow and a vehicle driving 2 lanes across from your vehi-cle enters the detection area
• When items such as a bicycle carrier are installed on the rear of the vehicle

3234-5. Using the driving support systems
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Driving
GS450h_300h_OM_OM30F92E_(EE)
■Conditions under which the Rear Crossing Traffic Alert function will not detect a vehi- cle
The Rear Crossing Traffic Alert function is not designed to detect the following types of
vehicles and/or objects.
●Small motorcycles, bicycles, pedestrians etc.*
●Vehicles approaching from directly behind
●Guardrails, walls, signs, parked vehi cles and similar stationary objects*
●Vehicles moving away from your vehicle
●Vehicles approaching from the parking spaces next to your vehicle*
●Vehicles backing up in the parking space next to your vehicle*
*: Depending on conditions, detection of a vehicle and/or object may occur.
■Conditions under which the Rear Crossing Traffic Alert function may not function cor- rectly
The Rear Crossing Traffic Alert function may not detect vehicles correctly in the follow- ing conditions:
●During bad weather such as heavy rain, fog, snow etc.
●When ice or mud etc. is attached to the rear bumper
●When multiple vehicles approach continuously
●Shallow angle parking
●When a vehicle is approaching at high speed
●When parking on a steep incline, such as hills, a dip in the road etc.
●Directly after the BSM function is turned on
●When your vehicle is towing a trailer (vehicles with towing package)
●When items such as a bicycle carrier are installed on the rear of the vehicle
●Directly after the hybrid system is started with the BSM function is turned on
●When the sensors cannot detect vehicles
because of obstacles