
566
GS450h_OM_OM30F70U_(U)
7-2. Steps to take in an emergency
If your vehicle overheats
■If the needle of the engine coolant temperature gauge enters the red
zone
Stop the vehicle in a safe place an d turn off the air conditioning sys-
tem, and then stop the hybrid system.
If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
After the hybrid system has cooled down sufficiently, inspect the
hoses and cooling system for leaks.
Radiator
Cooling fans
If a large amount of coolant
leaks, immediately contact your
Lexus dealer.
The following may indicate that your vehicle is overheating.
●The needle of the engine coolant temperature gauge ( P. 91) enters
the red zone or a loss of hybrid system power is experienced. (For
example, the vehicle speed does not increase.)
●“Hybrid System Overheat” ( P. 527) is shown on the multi-informa-
tion display.
●Steam comes out from under the hood.
Correction procedures
1
2
3
1
2

5677-2. Steps to take in an emergency
GS450h_OM_OM30F70U_(U)
7
When trouble arises
The coolant level is satisfactory if it is between the “FULL” and
“LOW” lines on the reservoir.
Reservoir
“FULL”
“LOW”
Coolant inlet cap
Add coolant if necessary.
( P. 569)
Water can be used in an emer-
gency if engine coolant is unavail-
able.
Start the hybrid system and turn the air conditioning system on to
check that the radiator cooling fa ns operate and to check for coolant
leaks from the radiator or hoses.
The fans operate when the air conditioning system is turned on immediately
after a cold start. Confirm that the fans are operating by checking the fan
sound and air flow. If it is difficult to check these, turn the air conditioning sys-
tem on and off repeatedly. (The fans may not operate in freezing tempera-
tures.)
If the fans are not operating:
Stop the hybrid system immediately and contact your Lexus dealer.
If the fans are operating:
Have the vehicle inspected at the nearest Lexus dealer.
4
1
2
3
4
5
6
7

594
GS450h_OM_OM30F70U_(U)
8-1. Specifications
Glossary of tire terminology
Tire related termMeaning
Cold tire inflation pres-
sureTire pressure when the vehicle has been parked for
three hours or more, or has not been driven more
than 1 mile or 1.5 km under that condition
Maximum inflation pres-
sureThe maximum cold inflated pressure to which a tire
may be inflated, shown on the sidewall of the tire
Recommended inflation
pressureCold tire inflation pressure recommended by a man-
ufacturer
Accessory weight
The combined weight (in excess of those standard
items which may be replaced) of hybrid transmission,
power steering, power brakes, power windows,
power seats, radio and heater, to the extent that these
items are available as factory-installed equipment
(whether installed or not)
Curb weight
The weight of a motor vehicle with standard equip-
ment, including the maximum capacity of fuel, oil and
coolant, and if so equipped, air conditioning and
additional weight optional engine
Maximum loaded vehicle
weight
The sum of:
(a) Curb weight
(b) Accessory weight
(c) Vehicle capacity weight
(d) Production options weight
Normal occupant weight150 lb. (68 kg) times the number of occupants speci-
fied in the second column of Table 1
* that follows
Occupant distributionDistribution of occupants in a vehicle as specified in
the third column of Table 1
* below
Production options weight
The combined weight of installed regular production
options weighing over 5 lb. (2.3 kg) in excess of the
standard items which they replace, not previously
considered in curb weight or accessory weight,
including heavy duty brakes, ride levelers, roof rack,
heavy duty 12-volt battery, and special trim
RimA metal support for a tire or a tire and tube assembly
upon which the tire beads are seated

634Alphabetical index
GS450h_OM_OM30F70U_(U)
Alphabetical index
A/C ............................................................ 335Air conditioning filter....................... 458
Changing the rear seat settings ................................................. 347
Front automatic air conditioning system ................................................. 335
Humidity sensor .................................. 351
Micro dust and pollen filter ...........349
Rear air conditioning system....... 355
S-FLOW mode ..................................349
ABS (Anti-lock Brake System)....... 283 Function ................................................. 283
Warning light ...................................... 504
Warning message .............................. 517
Adaptive Front-lighting System (AFS) ........................................................219
Adaptive Variable Suspension system (AVS)...................................... 284
AFS (Adaptive Front-lighting System) ....................................................219
Air conditioning filter .......................... 458
Air conditioning system ..................... 335 Air conditioning filter....................... 458
Changing the rear seat settings ................................................. 347
Front automatic air conditioning system ................................................. 335
Humidity sensor .................................. 351
Micro dust and pollen filter ...........349
Rear air conditioning system....... 355
S-FLOW mode ..................................349 Airbags ........................................................ 38
Airbag operating conditions .......... 46
Airbag precautions for your child ......................................... 41
Airbag warning light ........................504
Correct driving posture .................... 30
Curtain shield airbag operating conditions ....................... 46
Curtain shield airbag precautions .......................................... 44
Front passenger occupant classification system......................... 49
General airbag precautions ............. 41
Locations of airbags............................ 38
Modification and disposal of airbags............................................... 45
Side airbag operating conditions ............................................. 46
Side airbag precautions ...................... 41
Side and curtain shield airbags operating conditions ....................... 46
Side and curtain shield airbags precautions ............................................ 41
SRS airbags ............................................. 38
Alarm ........................................................... 83 Alarm .......................................................... 83
Warning buzzer...................... 503, 513
Anchor brackets........................................ 61
Antennas (smart access system with push-button start) ..................... 125
Anti-lock Brake System (ABS) ...... 283 Function .................................................. 283
Warning light .......................................504
Warning message............................... 517
A

640Alphabetical index
GS450h_OM_OM30F70U_(U)
Hands-free system (for cellular phone)
*
HD Radio® system*
Head restraints ....................................... 158
Headlights ................................................. 217 Adaptive Front-lighting System (AFS) .................................... 219
Discharge headlights precautions ......................................... 491
Headlight leveling warning message ............................ 516
Light switch ............................................. 217
Replacing light bulbs ....................... 489
Wattage ................................................. 583
Headlights aim ............................ 477, 624
Head-up display..................................... 104
Heaters Air conditioning system ................. 335
Heated steering wheel ................... 380
Seat heaters ......................................... 382
Outside rear view mirrors ............ 360
High-voltage components ...................76
Hood .......................................................... 426 Open ........................................................426
Warning message ............................ 520
Hooks Cargo hooks ........................................ 373
Coat hooks .......................................... 390
Luggage hook ..................................... 373
Retaining hooks (floor mat) ............. 28
Utility hook ............................................392 Horn............................................................. 216
Hybrid battery (traction battery) ....... 76
Hybrid battery (traction battery)
air vents ..................................................... 77
Hybrid system............................................ 72 Emergency shut off system .............. 77
Energy monitor/consumption screen.......................... 111
EV drive mode ...................................200
High voltage components ................76
Hybrid System Indicator ................... 94
Hybrid system precautions ..............76
Hybrid vehicle driving tips ..............316
If the hybrid system will not start .......................................554
Overheating.........................................566
Power (ignition) switch.....................193
Starting the hybrid system...............193
Vehicle proximity notification system ......................................................73
Hybrid System Indicator .......................94
Hybrid transmission ............................ 203 If the shift lever cannot be shifted from P ............556
Paddle shift switches........................205
S mode.................................................... 206
H

645Alphabetical index
GS450h_OM_OM30F70U_(U)
Pre-Collision System (PCS) ............ 290Function ................................................. 290
PCS OFF switch ................................ 292
Warning light ...................................... 505
Warning message .......................515, 526, 532
Radar cruise control (dynamic radar cruise control) ........................ 239
Radiator .................................................... 436
Radio
*
RBDS (Radio Broadcast Data Systems)
*
Rear air conditioning system ........... 355
Rear door sunshades ..........................388
Rear personal lights............................. 364
Rear side marker lights ........................ 217 Light switch ............................................. 217
Replacing light bulbs ....................... 489
Welcome light illumination cont rol ..........................123
Rear seat heaters.................................. 382
Rear sunshade ....................................... 387 Operation ..............................................387
Reverse operation feature............ 388 Rear turn signal lights ......................... 209
Replacing light bulbs ....................... 487
Turn signal lever ................................. 209
Wattage .................................................583
Rear view mirror Inside rear view mirror...................... 162
Outside rear view mirrors ..............164
Rear view monitor system
*
Rear window defoggers .................... 360
Refueling.................................................. 230 Capacity................................................. 576
Fuel types............................................... 576
Opening the fuel tank cap ............ 232
When the fuel filler door cannot be opened ......................... 233
Regenerative braking............................. 74
Remote Touch
*.....................................326
Replacing Electronic key battery .....................460
Fuses ........................................................ 462
Light bulbs............................................. 479
Tires ............................................................541
Reporting safety defects for U.S. owners .................................... 612
Resetting the message indicating maintenance is required .................. 416
Road accident cautions ......................... 79
R
*: Refer to the “NAVIGATION AND MULTIMEDIA SYSTEM OWNER’S MANUAL”.