ECU LEXUS GS300H 2019 Workshop Manual

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
4
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.

2194-2. Driving procedures
4
Driving
GS450h_300h_OM_OM30F92E_(EE)
If the hybrid system is stopped with the shift lever in a position other than P, the
power switch will not be turned off but instead be turned to ACCESSORY
mode. Perform the following procedure to turn the switch off:
Check that the parking brake is set.
Shift the shift lever to P.
Check that “Turn Off Vehicle” is displayed on the multi-information display
and then press the power switch once.
Check that “Turn Off Vehicle” on the multi-information display is off.
■Auto power off function
If the vehicle is left in ACCESSORY mode for more than 20 minutes or ON mode (the
hybrid system is not operating) for more than an hour with the shift lever in P, the power switch will automatically turn off. However, this function cannot entirely prevent 12-voltbattery discharge. Do not leave the vehicle with the power switch in ACCESSORY or
ON mode for long periods of time when the hybrid system is not operating.
■Sounds and vibrations specific to a hybrid vehicle
 P. 79
■Electronic key battery depletion
 P. 136
■When the ambient temperature is low, such as during winter driving conditions
When starting the hybrid system, the flashing time of the “READY” indicator may be long. Leave the vehicle as it is until the “REA DY” indicator is steady on, as steady means the vehicle is able to move.
■Conditions affecting operation
 P. 155
■Notes for the push-start function
 P. 157
■If the hybrid system does not start
●The immobilizer system may not have been deactivated. (P. 85)
Contact any authorized Lexus retailer or Le xus authorized repairer, or any reliable repairer.
●Check that the shift lever is securely set in P. The hybrid system may not start if the shift
lever is displaced out of P. “Shift to P posi tion to Start” will be displayed on the multi- information display.
■Steering lock
After turning the power switch off and opening and closing the doors, the steering wheel will be locked due to the steering lock func tion. Operating the power switch again auto- matically cancels the steering lock.
When stopping the hybrid system with the shift lever in a position other
than P
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2394-3. Operating the lights and wipers
4
Driving
GS450h_300h_OM_OM30F92E_(EE)
AFS (Adaptive Front-lighting System) secures excellent visibility at intersections
and on curves by automatically adjusting the direction of the light axis of the
headlights according to vehicle speed and the degree of the tire’s angle as con-
trolled by steering input.
AFS operates at speeds of 10 km/h (6 mph) or higher.
■Deactivating AFS
Settings can be changed from on the multi-information display
( P. 111).
Press or on the meter control switch and select “AFS”.
Press on the meter control
switch and select “Off”.
The indicator turns on when the AFS is deactivated.
AFS (Adaptive Front-lighti ng System) (if equipped)
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2504-3. Operating the lights and wipers
GS450h_300h_OM_OM30F92E_(EE)
Fog light switch
Turns the front and rear fog
lights off
Turns the front fog lights on
Turns both front and rear fog
lights on
Releasing the switch ring returns it to
.
Operating the switch ring again turns
only the rear fog light off.
■Fog lights can be used when
Front fog lights: The headlights or the front position lights are turned on. Rear fog light: The front fog lights are turned on.
The fog lights secure excellent visibility in difficult driving conditions, such as
in rain and fog.
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4-4. Refueling
Driving
GS450h_300h_OM_OM30F92E_(EE)
Opening the fuel tank cap
●Turn the power switch off and ensure that all the doors and windows are
closed.
●Confirm the type of fuel.
■Fuel types
 P. 559
■Fuel tank opening for unleaded gasoline
To help prevent incorrect fueling, your vehicle has a fuel tank opening that only accom- modates the special nozzle on unleaded fuel pumps.
Perform the following steps to open the fuel tank cap:
Before refueling the vehicle
WARNING
■When refueling the vehicle
Observe the following precautions while refueling the vehicle. Failure to do so may result in death or serious injury.
●After exiting the vehicle and before opening the fuel door, touch an unpainted metalsurface to discharge any static electricity. It is important to discharge static electricity before refueling because sparks resulting fr om static electricity can cause fuel vapors
to ignite while refueling.
●Always hold the grips on the fuel tank cap and turn it slowly to remove it. A whooshing sound may be heard when the fuel tank cap is loosened. Wait until the
sound cannot be heard before fully removing the cap. In hot weather, pressurized fuel may spray out the filler neck and cause injury.
●Do not allow anyone that has not discharged static electricity from their body to come
close to an open fuel tank.
●Do not inhale vaporized fuel. Fuel contains substances that are harmful if inhaled.
●Do not smoke while refueling the vehicle.Doing so may cause the fuel to ignite and cause a fire.
●Do not return to the vehicle or touch any person or object that is statically charged.
This may cause static electricity to build up, resulting in a possible ignition hazard.
■When refueling
Observe the following precautions to prevent fuel overflowing from the fuel tank:
●Securely insert the fuel nozzle into the fuel filler neck.
●Stop filling the tank after the fuel nozzle automatically clicks off.
●Do not top off the fuel tank.

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

3745-4. Using the storage features
GS450h_300h_OM_OM30F92E_(EE)
Trunk features
Raise the hooks when needed.
The cargo hooks are provided for
securing loose items.
Pull the strap when using the hook.
Cargo hooks
WARNING
To avoid injury, always return the cargo hooks to their stowed positions when not in use.
Luggage hook
NOTICE
Do not hang any object heavier than 5 kg (11 lb.) on the luggage hook.

3765-4. Using the storage features
GS450h_300h_OM_OM30F92E_(EE)
Loosen the belt
Tighten the belt
Warning reflector storage belt
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To prevent damage to the warning reflector stor- age belt when it is not in use, fold the belt (as
shown in ) and secure it with the clip ( ).12