
5
1 8
7
6
5
4
3
2
GS450h_300h_OM_OM30F92E_(EE) 6-3. Do-it-yourself maintenance
Do-it-yourself service precautions ................................399
Hood ................................................ 401
Positioning a floor jack.............402
Engine compartment............... 403
12-volt battery............................... 412
Tires .................................................. 416
Tire inflation pressure...............429
Wheels............................................. 431
Air conditioning filter................433
Electronic key battery ..............435
Checking and replacing fuses .............................................. 437
Light bulbs ..................................... 442
7-1. Essential information Emergency flashers...................452
If your vehicle has to be stopped in an
emergency.................................453 7-2. Steps to take in an
emergency
If your vehicle needs to be towed ................................454
If you think something is wrong .......................................459
If a warning light turns on or a warning buzzer
sounds..........................................460
If a warning message is displayed................................. 466
If you have a flat tire (vehicles with spare tire) ..... 498
If you have a flat tire (vehicles without spare
tire) ............................................... 509
If the hybrid system will not start................................523
If the parking brake cannot be released.................525
If the electronic key does not operate properly ............. 527
If the 12-volt battery is discharged ................................ 530
If your vehicle overheats .........535
If the vehicle becomes stuck.............................................. 542
7When trouble arises

15
Pictorial index
GS450h_300h_OM_OM30F92E_(EE) Windshield wipers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 251
Precautions against winter season . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 334
To prevent freezing (windshield wiper de-icer)
*1
. . . . . . . . . . . . . . . . . . . . . . P. 352
Precautions against car wash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 392
Fuel filler door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P . 257
Refueling method. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 257
Fuel type/fuel tank capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 549
Tires. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 416
Tire size/inflation pressure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 555
Winter tires/tire chain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 33 4
Checking/rotation/tire pressure warning system *1
. . . . . . . . . . . . . . . . . . . . . P. 416
Coping with flat tires. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 498, 509
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 401
Opening . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 401
Engine compartment cover. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 405
Engine oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 550
Coping with overheat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 535
Warning messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 468
Headlights/front position lights/daytime running lights . . . . . . . . . . . P. 237
Front turn signal lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 231
Front fog lights/rear fog light *2
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 250
Side turn signal lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 231
Tail lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 237
Stop lights
Emergency brake signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 325
Rear turn signal lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 231
Back-up light *2
Shifting the shift lever to R . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 224
License plate lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 237
4
5
6
7
Light bulbs of the exterior lights for driving
(Replacing method: P. 442, Watts: P. 558)
*1
: If equipped
* 2
: They may be located on the opposite side depending on the target region.
8
9
10
11
12

961-3. Theft deterrent system
GS450h_300h_OM_OM30F92E_(EE)
■Tilt sensor detection cons iderations (if equipped)
The sensor may trigger the alarm in the following situations:
●The vehicle is transported by a ferry, trailer, train, etc.
●The vehicle is parked in a parking garage.
●The vehicle is inside a car wash that moves the vehicle.
●Any of the tires loses air pressure.
●The vehicle is jacked up.
●An earthquake occurs or the road caves in.
NOTICE
■To ensure the intrusion sensor function correctly
●Installing accessories other than genuine Lexus parts or leaving objects between the
driver’s seat and front passenger’s seat may reduce the detection performance.
●To ensure that the sensors operate properly,
do not touch or cover them.
●Do not spray air fresheners or other products
directly into the sensor holes.

201
4-1. Before driving
4
Driving
GS450h_300h_OM_OM30F92E_(EE)
■When starting off on a uphill
The hill-start assist control is available. ( P. 325)
■For fuel-efficient driving
Keep in mind that hybrid vehicles are similar to conventional vehicles, and it is necessary
to refrain from activities such as sudden acceleration, etc. Refer to “Hybrid vehicle driv-
ing tips”. ( P. 331)
■Driving in the rain
●Drive carefully when it is ra ining, because visibility will be reduced, the windows may
become fogged-up, and the road will be slippery.
●Drive carefully when it starts to rain, because the road surface will be especially slip-
pery.
●Refrain from high speeds when driving on an expressway in the rain, because there may
be a layer of water between the tires and the road surface, preventing the steering and
brakes from operating properly.
■Restraining hybrid system outp ut (Brake Override System)
●When the accelerator and brake pedals are depressed at the same time, the hybrid sys-
tem output may be restrained.
●A warning message is displayed on the mult i-information display while the system is
operating. ( P. 485)
■Restraining sudden start (Drive-Start Control)
●When the following unusual operation is pe rformed, the hybrid system output may be
restrained.

2064-1. Before driving
GS450h_300h_OM_OM30F92E_(EE)
WARNING
Observe the following precautions.
Failure to do so may result in death or serious injury.
■When taking a nap in the vehicle
Always turn the hybrid system off. Otherwise, if you accidentally move the shift lever or
depress the accelerator pedal, this could cause an accident or fire due to hybrid system
overheating. Additionally, if the vehicle is parked in a poorly ventilated area, exhaust
gases may collect and enter the vehicle, lead ing to death or a serious health hazard.
■When braking
●When the brakes are wet, drive more cautiously.
Braking distance increases when the brakes are wet, and this may cause one side of
the vehicle to brake differently than the other side. Also, the parking brake may not
securely hold the vehicle.
●If the electronically controlled brake system does not operate, do not follow other
vehicles closely and avoid hills or sharp turns that require braking.
In this case, braking is still possible, but the brake pedal should be depressed more
firmly than usual. Also, the braking distance will increase. Have your brakes fixed
immediately.
●The brake system consists of 2 or more indi vidual hydraulic systems; if one of the sys-
tems fails, the other(s) will still operate. In this case, the brake pedal should be
depressed more firmly than usual and the braking distance will increase. Have your
brakes fixed immediately.
■If the vehicle becomes stuck
Do not spin the wheels excessively when any of the tires is up in the air, or the vehicle is
stuck in sand, mud, etc. This may damage the driveline components or propel the vehi-
cle forward or backward, causing an accident.

2124-1. Before driving
GS450h_300h_OM_OM30F92E_(EE)
Installation positions for the towing hitch/bracket and hitch ball
436 mm (17.2 in.)
455 mm (17.9 in.)
454 mm (17.9 in.)
475 mm (18.7 in.)
476 mm (18.7 in.) 500 mm (19.7 in.)
520 mm (20.5 in.)
543 mm (21.4 in.)
560 mm (22.0 in.)1
2
3
4
5
6
7
8
9
289 mm (11.4 in.)
322 mm (12.7 in.)
374 mm (14.7 in.)
592 mm (23.3 in.)
1201 mm (47.3 in.)
61 mm (2.4 in.)
56 mm (2.2 in.)
37 mm (1.5 in.)
27 mm (1.1 in.)18 mm (0.7 in.)
12 mm (0.5 in.)
8 mm (0.3 in.)
401 mm (15.8 in.)
*1
408 mm (16.1 in.) *2
410 mm (16.1 in.) *3
* 1
:225/50R17 tires
* 2
:235/45R18 tires
* 3
: 235/40R19 tires or 265/35R19 tires10
11
12
13
14
15
16
17
18
19
20
21
22

213
4-1. Before driving
4
Driving
GS450h_300h_OM_OM30F92E_(EE)
■Tire information
●Increase the tire inflation pressure to 20.0 kPa (0.2 kgf/cm 2
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 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 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 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.

2364-2. Driving procedures
GS450h_300h_OM_OM30F92E_(EE)
■When the parking brake is set automatically while the system is holding the brakes
The parking brake will not be released auto matically. Perform one of the following proce-
dures to release the parking brake and conf irm that the parking brake indicator light
turns off. ( P. 232)
●With the brake pedal depressed, operate the parking brake switch.
●Fasten your seat belt, check that the shift leve r is in either D or R and slowly depress the
accelerator pedal.
■Warning message and buzzers
Warning messages and buzzers are used to indicate a system malfunction or to inform
the driver of the need for caution. ( P. 466)
WARNING
■When the vehicle is on a steep incline
When using the brake hold system on a steep incline exercise caution. The brake hold
function may not hold the vehicle in such a situation.
■When stopped on a slippery road
The system cannot stop the vehicle when the gripping ability of the tires has been
exceeded. Do not use the system when stopped on a slippery road.
NOTICE
■When parking the vehicle
The brake hold system is not designed fo r use when parking the vehicle for a long
period of time. Turning the power switch o ff while the system is holding the brake may
release the brake, which would cause the vehicle to move. When operating the power
switch, depress the brake pedal, set the pa rking brake and shift the shift lever to P.