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

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)

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
427
5-1. Essential information
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably needs
adjustment or repair. Contact your Lexus dealer as soon as possible.
■ Visible symptoms
●Fluid leaks under the v
ehicle
(Water dripping from the air conditioning after use is normal.)
● Flat
-looking tires or uneven tire wear
●Engine coolant temper atur
e gauge needle continually points
higher than normal
■ A
udible symptoms
●Changes in e
xhaust sound
● Ex
cessive tire squeal when cornering
●Str
ange noises related to the suspension system
●P
inging or other noises related to the hybrid system
■ Oper
ational symptoms
●Engine mis
sing, stumbling or running rough
●A
ppreciable loss of power
●V
ehicle pulls heavily to one side when braking
●V
ehicle pulls heavily to one side when driving on a level road
● L
oss of brake effectiveness, sp ongy feeling, pedal almost touches
the floor

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.
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