2013 Lexus GS300h radiator

7326-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
Light bulbs (P. 803)
• Bulb with same number and watt-
age rating as original
• Phillips-head screwdriver
• Flathead screwdriver
•Wrench
Radiator and condenser (P. 747)
Tire inflation pressure (P. 772)• Tire pressure gauge
• Compressed air source
Wa s h e r f l u i d (P. 748)
• Water or washer fluid containing
antifreeze (for winter use)
• Funnel (used only for adding
water or washer fluid)
CAUTION
The engine compartment contains many mechanisms and fluids that may
move suddenly, become hot, or become electrically energized. To avoid death
or serious injury, observe the following precautions.
When working on the engine compartment
Make sure that the “POWER ON” on the multi-information display and
the “READY” indicator are both off.
Keep hands, clothing and tools away from the moving fan and engine
drive belt.
Be careful not to touch the engine, power control unit, 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 and rags, in the
engine compartment.
Do not smoke, cause sparks or expose an open flame to fuel. Fuel fumes
are flammable.
Take care because brake fluid can harm your hands or eyes and damage
painted surfaces. If fluid gets on your hands or in your eyes, flush the
affected area with clean water immediately. If you still experience dis-
comfort, consult a doctor.
ItemsParts and tools

733 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30D53E_(EE)
CAUTION
When working near the electric cooling fans or radiator grille
Be sure the power switch is off.
With the power switch in ON mode, the electric cooling fans may automat-
ically start to run if the air conditioning is on and/or the coolant temperature
is high.
(P. 747)
Safety glasses
Wear safety glasses to prevent flying or falling material, fluid spray, etc.
from getting in your eyes.
NOTICE
If you remove the air cleaner filter
Driving with the air cleaner filter removed may cause excessive engine
wear due to dirt in the air.
If the fluid level is low or high
It is normal for the brake fluid level to go down slightly as the brake pads
wear or when the fluid level in the accumulator is high.
If the reservoir needs frequent refilling, it may indicate a serious problem.

7386-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
Engine compartment
GS300h
12-volt battery
P. 7 4 9
Power control unit coolant
reservoir (P. 745)
Engine oil level dipstick
(P. 741)
Engine oil filler cap (P.
742)
Engine coolant reservoir
(P. 744)Fuse box (P. 782)
Washer fluid tank (P. 748)
Electric cooling fans
Condenser (P. 747)
Radiator (P. 747)1
2
3
4
5
6
7
8
9

739 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30D53E_(EE)
GS450h
12-volt battery
P. 7 4 9
Engine oil level dipstick
(P. 741)
Engine coolant reservoir
(P. 744)
Engine oil filler cap (P.
742)
Power control unit coolant
reservoir (P. 745)Fuse box (P. 782)
Washer fluid tank (P. 748)
Electric cooling fans
Condenser (P. 747)
Radiator (P. 747)1
2
3
4
5
6
7
8
9

7466-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
Coolant selection
Only use “Toyota Super Long Life Coolant” or a similar high quality eth-
ylene glycol based non-silicate, non-amine, non-nitrite, and non-borate cool-
ant with long-life hybrid organic acid technology.
“Toyota Super Long Life Coolant” is a mixture of 50% coolant and 50%
deionized water. (Minimum temperature: -35C [-31F])
For more details about coolant, contact any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
If the coolant level drops within a short time of replenishing
Visually check the radiator, hoses, engine/power control unit coolant reser-
voir caps, drain cock and water pump.
If you cannot find a leak, have any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional, test the cap and check for
leaks in the cooling system.
CAUTION
When the hybrid system is hot
Do not remove the engine/power control unit coolant reservoir caps or the
coolant inlet cap. (P. 9 2 1 )
The cooling system may be under pressure and may spray hot coolant if the
cap is removed, causing serious injuries, such as burns.
NOTICE
When adding coolant
Coolant is neither plain water nor straight antifreeze. The correct mixture of
water and antifreeze must be used to provide proper lubrication, corrosion
protection and cooling. Be sure to read the antifreeze or coolant label.
If you spill coolant
Be sure to wash it off with water to prevent it from damaging parts or paint.

747 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30D53E_(EE)
Check the radiator and condenser and clear away any foreign
objects.
If either of the above parts is extremely dirty or you are not sure of
their condition, have your vehicle inspected by any authorized
Lexus dealer or repairer, or another duly qualified and equipped
professional.
Radiator and condenser
CAUTION
When the hybrid system is hot
Do not touch the radiator or condenser as they may be hot and cause serious
injuries, such as burns.

9187-2. Steps to take in an emergency
GS450h_300h_OM_OM30D53E_(EE)
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 coolant level is satisfactory if it is between the “FULL”
and “LOW” lines on the reservoir.
Reservoir
“FULL”
“LOW”
Coolant inlet cap
3
1
2
GS300hGS450h
4
1
2
3
4
GS300hGS450h

9197-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30D53E_(EE)
Add coolant if necessary. (P. 923)
Water can be used in an emergency if engine coolant is unavailable.
Start the hybrid system and turn the air conditioning system on
to check that the radiator cooling fans operate and to check for
coolant leaks from the radiator or hoses.
The fans operate when the air conditioning system is turned on immedi-
ately 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 system on and off repeatedly. (The fans may not operate in
freezing temperatures.)
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.
5
GS300hGS450h
6
7