Inverter Lexus GS450h 2007 Driving Comfort TOC / LEXUS 2007 GS450H THROUGH JUNE 2006 PROD. OWNER'S MANUAL (OM30727U)

5
1-1. Hybrid system
1
Before driving
High voltage components
Take care when handling the hybrid system, as it contains a high voltage
system (about 650V at maximum) as well as parts that become
extremely hot when the hybrid system is operating. Obey the caution
labels attached to the vehicle.
Inverter unit
Air conditioning compressor
Hybrid battery (Traction bat-
tery)
DC/DC converter Service plug
Electric motor (Traction motor)
High voltage cables (orange
color)
Caution label

174
2-5. Driving information
Winter driving tips
Carry out the necessary preparations and inspections before driving the
vehicle in winter. Always drive the vehicle in a manner appropriate to the
prevailing weather conditions.
■ Pre-winter preparations
●Use fluids that ar
e appropriate to the prevailing outside tempera -
tures.
• Engine oil
• Engine/inverter coolant
• Washer fluid
● Ha
ve a service technician inspect th e level and specific gravity of
battery electrolyte.
● Ha
ve the vehicle fitted with four snow tires or purchase a set of
tire chains for the rear tires.
Ensure that all tires are the same si ze and brand, and that chains match
the size of the tires.
● Tire inflation pressure falls in winter as the outside temperature
falls. Add 2.8 to 4.3 psi (20 to 30 kPa, 0.2 to 0.3 kgf/cm2 or bar)
to the standard tire inflation pressure.

351
4-2. Maintenance
4
Maintenance and care
General maintenance
Engine compartment
Luggage compartment
ItemsCheck points
Brake fluid• At the correct level? (P. 3 7 0 )
Engine/inverter coolant• At the correct level? ( P. 3 6 8 )
Engine oil• At the correct level? ( P. 3 6 3 )
Exhaust system• No fumes or strange sounds?
Radiator/condenser/hoses• Not blocked with foreign matter? 
( P. 3 6 9 )
Wa s h e r f l u i d• At the correct level? ( P. 3 74 )
ItemsCheck points
12 volt battery• Maintenance-free ( P. 3 7 1 )
Listed below are the general maintenance items that should be performed
at the intervals specified in the “Warranty and Services Guide/Owner’s
Manual Supplement”. It is recommend ed that any problem you notice
should be brought to the attention of your Lexus dealer or qualified service
shop for advice.

355
4
Maintenance and care
4-3. Do-it-yourself maintenance
Do-it-yourself service precautions
If you perform maintenance yourself, be sure to follow the correct proce-
dure given in these sections.
ItemsPa r t s a n d t o o l s
12 volt battery condition (P. 3 7 1)
•Grease
• Conventional wrench 
(for terminal clamp bolts)
Brake fluid level ( P. 3 7 0 )
• FMVSS No.116 DOT 3 or SAE
J1703 brake fluid
•Rag or paper towel
• Funnel (used only for adding brake
fluid)
Engine/inverter coolant level 
( P. 3 6 8 )
• “Toyota Super Long Life Coolant”
or similar high quality ethylene gly-
col based non-silicate, non-amine,
non-nitrate and non-borate coolant
with long-life hybrid organic acid
technology.
For the U.S.A.: 
“Toyota Super Long Life Coolant”
is pre-mixed with 50% coolant and
50% deionized water.
For Canada: 
“Toyota Super Long Life Coolant”
is pre-mixed with 55% coolant and
45% deionized water.
• Funnel (used only for adding cool- ant)

356
4-3. Do-it-yourself maintenance
CAUTION
The engine compartment contains many mechanisms and fluids that may move sud-
denly, become hot, or become electrically energized. To avoid death or serious injury.
■When working on the engine compartment:
●Keep hands, clothing, and tools away from the moving fan and engine drive belt.
●Be careful not to touch the engine, inverter, radiator, exhaust manifold, etc. right
after driving as they may be hot. Oil and other fluids may also be hot.
●Do not leave anything that may burn easily , such as paper or rags, in the engine
compartment.
●Do not smoke, cause sparks or expose an open flame to fuel or the battery. Fuel
and battery fumes are flammable.
●Be extremely cautious when working on the battery. It contains poisonous and
corrosive sulfuric acid.
ItemsPa r t s a n d t o o l s
Engine oil level ( P. 3 6 3 )
• “Toyota Genuine Motor Oil” or
equivalent
• Rag or paper towel, funnel (used only for adding engine oil)
Fuses ( P. 3 9 5 )• Fuse with same amperage rating as
original
Headlight aim ( P. 4 1 1 )• Phillips-head screwdriver
Radiator and condenser (P. 3 6 9 )
Tire inflation pressure ( P. 3 8 5 )• Tire pressure gauge
• Compressed air source
Wa s h e r f l u i d ( P. 3 74 )
• Water washer fluid containing anti-
freeze (for winter use)
•Funnel

361
4-3. Do-it-yourself maintenance
4
Maintenance and care
Engine compartment
■12 volt battery
P. 3 7 1
Engine oil level dipstick 
( P. 363)
Engine oil filler cap 
( P. 364)
Brake fluid reservoir (P. 370)
Fuse box ( P. 395)Washer fluid tank 
( P. 3 74 )
Gasoline engine/inverter 
coolant reservoir ( P. 368)
Electric cooling fans
Condenser ( P. 369)
Radiator ( P. 369)

368
4-3. Do-it-yourself maintenance
Coolant
The coolant level is satisfactory if it is between the “FULL” and “LOW”
lines on the reservoir when the hybrid system is cold.
Reservoir cap
Full
Low
If the level is on or below the
“LOW” line, add coolant up to the
“FULL” line.
■If the coolant level drops within a short time after replenishing
Visually check the radiator, hoses, reservoir cap, radiator cap, drain cock and water
pump
. 
If you cannot find a leak, have your Lexus dealer pressure test the cap and check for
le
aks in the cooling system.
■Coolant selection
Only use “Toyota Super Long Life Coolant” or similar hig
h quality ethylene glycol
based non-silicate, non-amine, non-nitrite, and non-borate coolant with long-life
hybrid organic acid technology.
U.S.A.: “Toyota Super Long Life Coolant” is a
mixture of 50% coolant and 50%
deionized water. (Enabled: -31F [-35 C])
Canada: “Toyota Super Long Life Coolant” is a mixture of 55% coolant and 45% de
ionized water. (Enabled: -44 F [-42C])
For more details about engine/inverter coolant, contact your Lexus dealer.

5
When trouble arises
475
5-2. Steps to take in an emergency
If your vehicle overheats
■Electric motor (traction motor) and inverter
If the message “HYBRID SYSTEM OVERHEAT” is displayed on the
multi-information display.
■ Ga
soline engine
If the needle of the engine co olant temper
ature gauge enters the
red zone, the gasoline engine has probably overheated.
Observe the following steps: Stop the vehicle in a safe place and turn of
f the automatic air
conditioning system.
Check to see if steam is coming out from under the hood.
If you see steam: 
Stop the hybrid system and carefully lift the hood.
If you do not see steam: Leave the hybrid system running and carefully lift the hood.
Remove the engine compartment cover. ( P. 362 )
Check to see if the cooling fan is operating.
If the fan is operating: 
Wait until the engine coolant temperature gauge begins to
fall and then stop the hybrid s
ystem.
If the fan is not operating: 
Stop the hybrid system immed iately and call y
our local
Lexus dealer.
After the hybrid system has
cooled do
wn sufficiently, check
the coolant level and inspect the
radiator core (radiator) for any
leaks.
STEP1
STEP2
STEP3
STEP4
STEP5

484
6-1. Specifications
Cooling system
Ignition system
Capacity
Gasoline engine
Inverter9.8 qt. (9.3 L, 8.1 lmp.qt.)
3.0 qt. (2.9 L, 2.5 lmp.qt.)
Coolant type
Use either of the following:• “Toyota Super Long Life Coolant”
• Similar high-quality ethylene glycol-based non-sili- cate, non-amine, non-nitrite, and non-borate cool-
ant with long-life organic acid technology
Do not use plain water alone.
Spark plug
Make DENSO 
NGK
GapFK20HBR11 
ILFR6D11T 
0.043 in. (1.1 mm)
NOTICE
■Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust gap when tuning engine.

512
Alphabetical index
Emergency, in case ofIf a warning light turns on .............. 430
If a warning message is 
displayed ............................................ 436
If the hybrid system will not 
start........................................................ 466
If the shift lever cannot be 
shifted from P ................................... 467
If the 12 volt battery is 
discharged ......................................... 471
If you have a flat tire ............ 455, 456
If you lose your keys......................... 468
If you think something is 
wrong ....................................................427
If your vehicle becomes stuck..... 478
If your vehicle needs to be 
towed ................................................... 420
If your vehicle overheats ................ 475
When the electronic key battery 
is discharged .................................... 469
Energy monitor............................................ 6
Engine Compartment ....................................... 361
Hood........................................................ 358
How to start the hybrid system
.....101
If the hybrid system will not 
start........................................................ 466
Overheating......................................... 475
Power switch .......................................... 101
Engine compartment cover ............. 362
Engine coolant temperature 
gauge.........................................................110
Engine/inverter coolant Capacity ................................................. 484
Checking ............................................... 368
Preparing and checking 
before winter ...................................... 174 Engine oil
Capacity ................................................ 483
Checking............................................... 363
Preparing and checking  before winter...................................... 174
Engine oil maintenance data ........... 366
EPS (Electric Power Steering) ......... 162
Event data recorder ............................ 428
First-aid kit storage belt ..................... 332
Floor mats .................................................. 331
Fluid Brake ....................................................... 370
Washer.................................................... 374
Fog lights Switch ........................................................ 123
Wattage ................................................. 488
Foot light .................................................. 308
Front passenger's seat
belt 
reminder light ..................................... 433
Front seats Adjustment ............................................... 34
Driving position memory .................. 36
Front turn signal lights Wattage ................................................. 488
Fuel Capacity ................................................ 482
Fuel gauge ................................................ 110
Gas station information ................. 520
Information ........................................... 489
Refueling ................................................... 58
Messages .............................................. 450
Fuel filler door ........................................... 58
Fuses .......................................................... 395
F