2016 Lexus GS200t coolant temperature

4426-2. Maintenance
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■Does your vehicle need repairs?
Be on the alert for changes in performance and sounds, and visual tip-offs that indicate
service is needed. Some important clues are:
●Engine missing, stumbling or pinging
●Appreciable loss of power
●Strange engine noises
●A fluid leak under the vehicle (However, water dripping from the air conditioning sys-
tem after use is normal.)
●Change in exhaust sound (This may indicate a dangerous carbon monoxide leak. Drive
with the windows open and have the exhaust system checked immediately.)
●Flat-looking tires, excessive tire squeal when cornering, uneven tire wear
●Vehicle pulls to one side when driven straight on a level road
●Strange noises related to suspension movement
●Loss of brake effectiveness, spongy feeling brake pedal, pedal almost touches the floor,
vehicle pulls to one side when braking
●Engine coolant temperature continually higher than normal ( →P. 1 0 9 )
If you notice any of these clues, take your vehicle to any authorized Lexus dealer or
repairer, or another duly qualified and equipp ed professional as soon as possible. Your
vehicle may need adjustment or repair.
WA R N I N G
■If your vehicle is not properly maintained
Improper maintenance could result in serious damage to the vehicle and possible
death or serious injury.
■Handling of the battery
Battery posts, terminals and related accessories contain lead and lead compounds
which are known to cause brain damage. Wash your hands after handling. ( →P. 4 6 0 )

4446-3. Do-it-yourself maintenance
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WA R N I N G
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
●Keep hands, clothing and tools away from the moving fan and engine drive belt.
●Be careful not to touch the engine, 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 or the battery. Fuel or
the battery fumes are flammable.
●Be extremely cautious when working on the battery. It contains poisonous and corro-
sive sulfuric acid.
●Take care because brake fluid can harm your hands or eyes and damage painted sur-
faces. If fluid gets on your hands or in your eyes, flush the affected area with clean
water immediately. If you still experience discomfort, consult a doctor.
■When working near the electric cooling fans or radiator grille
Be sure the engine switch is off.
With the engine switch in IGNITION ON mode, the electric cooling fans may auto-
matically start to run if the air conditioning is on and/or the coolant temperature is high.
( → P. 4 6 0 )
■Safety glasses
Wear safety glasses to prevent flying or fallin g 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.

459 6-3. Do-it-yourself maintenance
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Maintenance and care
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■Intercooler coolant reservoir (GS200t only)Reservoir cap
“F” line
“L” line
If the level is on or below the “L” line,
add coolant up to the “F” line.
( → P. 5 9 6 )
■Coolant selection
Only use “Toyota Super Long Life Coolant” or a similar high quality ethylene glycol
based non-silicate, non-amine, non-nitrite, and non-borate coolant with long-life hybrid
organic acid technology.
“Toyota Super Long Life Coolant” is a mixt ure 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 coolant reservoir 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 sys-
tem.
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WA R N I N G
■When the engine is hot
Do not remove the engine coolant reservoi r cap, the intercooler coolant reservoir cap
or the coolant inlet cap. ( →P. 6 0 0 )
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 cool-
ing. 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.

5107-2. Steps to take in an emergency
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If you think something is wrong
●Fluid leaks under the vehicle.
(Water dripping from the air conditioning after use is normal.)
●Flat-looking tires or uneven tire wear
●Engine coolant temperature gauge needle continually points higher than nor-
mal.
●Changes in exhaust sound
●Excessive tire squeal when cornering
●Strange noises related to the suspension system
●Pinging or other noises related to the engine
●Engine missing, stumbling or running roughly
●Appreciable loss of power
●Vehicle pulls heavily to one side when braking
●Vehicle pulls heavily to one side when driving on a level road
●Loss of brake effectiveness, spongy feeling, pedal almost touches the floor
If you notice any of the following symptoms, your vehicle probably needs
adjustment or repair. Contact any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional as soon as possible.
Visible s ymp toms
Audible symptoms
Operational symptoms

5277-2. Steps to take in an emergency
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When trouble arises
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Indicates a malfunction in:• The SRS airbag system; or
• The seat belt pretensioner system
A buzzer also sounds.
→ Have the vehicle inspected by any authorized Lexus
dealer or repairer, or another duly qualified and
equipped professional.
Indicates a malfunction in:
•The ABS; or
• The brake assist system
A buzzer also sounds.
→ Immediately stop the vehicle in a safe place and
contact any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
Indicates that the engine coolant temperature is too high
A buzzer also sounds.
→ P. 5 9 6
(GS350/GS200t only)
Indicates a malfunction in the vehicle’s charging system.
→Immediately stop the vehicle in a safe place and
contact any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
Wa r n i n g m e s s a g eDetails/Actions

5967-2. Steps to take in an emergency
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If your vehicle overheats
●The needle of the engine coolant temperature gauge (→P. 108, 113) enters
the red zone or a loss of engine power is experienced. (For example, the vehi-
cle speed does not increase.)
●“Engine Coolant Temp High Stop in a Safe Place See Owner’s Manual” is shown
on the multi-information display.
●Steam is coming from under the hood.
Stop the vehicle in a safe place and turn off the air conditioning system, and
then stop the engine.
If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
After the engine has cooled down sufficiently, inspect the hoses and radiator
core (radiator) for any leaks.
Radiator
Cooling fans
If a large amount of coolant leaks, imme-
diately contact any authorized Lexus
dealer or repairer, or another duly quali-
fied and equipped professional.
The following may indicate that your vehicle is overheating.
Correction procedures
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5997-2. Steps to take in an emergency
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When trouble arises
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Start the engine and turn the air conditioning system on to check that the radi-
ator 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 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 system on and off repeatedly.
(The fans may not operate in freezing temperatures.)
If the fans are not operating:
Stop the engine immediately and contact any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
If the fans are operating:
Have the vehicle inspected at the nearest any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
■When adding engine coolant (GS350/GS200t)
Add coolant in accordance with the following procedure.
Remove caps A and B.
Add engine coolant through the inlet of cap A up to the “[AR/GR] B” line, and then
install cap A.
Add engine coolant through the inlet of cap B until it is full, and then install cap B.
GS200t only: When installing cap B, apply coolant to the O-ring on the end of cap B.
Cap A
Cap B
“[AR/GR] B” line (Target fill line)
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GS350 GS200t
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6007-2. Steps to take in an emergency
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WA R N I N G
■When inspecting under the hood of your vehicle
Observe the following precautions.
Failure to do so may result in serious injury such as burns.
●If steam is seen coming from under the hood, do not open the hood until the steam
has subsided. The engine compartment may be very hot.
●Keep hands and clothing (especially a tie, a scarf or a muffler) away from the fans and
belts. Failure to do so may cause the hands or clothing to be caught, resulting in seri-
ous injury.
●GS350: Do not loosen the coolant inlet cap
or the engine coolant reservoir cap while the
engine and radiator are hot.
High temperature steam or coolant could
spray out.
●GS F: Do not loosen the engine coolant res-
ervoir cap while the engine and radiator are
hot.
High temperature steam or coolant could
spray out.
●GS200t: Do not loosen the coolant inlet cap,
the engine coolant reservoir cap or the inter-
cooler coolant reservoir cap while the engine
and radiator are hot.
High temperature steam or coolant could
spray out.