Page 438 of 612

4387-3. Do-it-yourself maintenance
IS200t_EE(OM53D19E)
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
●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 and
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. 446)
■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.
Page 441 of 612
4417-3. Do-it-yourself maintenance
7
Maintenance and care
IS200t_EE(OM53D19E)For right-hand drive vehicles:
The battery and the fuse box in front of the battery are located on the opposite side of the
engine compartment.
Engine compartment
Fuse boxes (
→P. 4 6 9 )
Battery ( →P. 4 4 7 )
Intercooler
Engine oil level dipstick (→ P. 4 4 2 )
Engine oil filler cap ( →P. 443)
Engine coolant reservoir (→ P. 4 4 5 ) Wa s h e r f l u i d t a n k (
→P. 4 5 0 )
Electric cooling fans
Condenser ( →P. 4 4 6 )
Intercooler radiator ( →P. 4 4 6 )
Radiator ( →P. 4 4 6 )
Intercooler coolant reservoir (→ P. 4 4 5 )1
2
3
4
5
6
7
8
9
10
11
12
Page 445 of 612

4457-3. Do-it-yourself maintenance
7
Maintenance and care
IS200t_EE(OM53D19E)
■Engine coolant reservoir
The coolant level is satisfactory if it is between the “FULL” and “LOW” lines on
the reservoir when the engine is cold.Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the “LOW”
line, add coolant up to the “FULL”
line. ( →P. 557)
■Intercooler coolant reservoir
The coolant level is satisfactory if it is between the “F” and “L” lines on the res-
ervoir when the engine is cold.
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 5 7 )
■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 cap, 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.
Coolant
1
2
3
1
2
3
Page 446 of 612

4467-3. Do-it-yourself maintenance
IS200t_EE(OM53D19E)
Check the radiator, condenser and intercooler radiator and clear away any for-
eign objects.
If any of the above parts are 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.
CAUTION
■When the engine is hot
Do not remove the engine coolant reservoir cap or intercooler coolant reservoir cap.
(→ P. 557)
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.
Radiator, condenser an d intercooler radiator
CAUTION
■When the engine is hot
Do not touch the radiator, condenser or intercooler radiator as they may be hot and
cause serious injuries, such as burns.
Page 498 of 612

4988-2. Steps to take in an emergency
IS200t_EE(OM53D19E)
●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 think something is wrong
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
Page 510 of 612

5108-2. Steps to take in an emergency
IS200t_EE(OM53D19E)
Indicates a malfunction in:
•The ABS; or
• The brake assist systemA buzzer also sounds.
→ Have the vehicle inspected by 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 5 7
(If equipped)
Indicates that the radar sensor is dirty or covered with
ice
A buzzer also sounds.
→ Clean the sensor.
(If equipped)
Indicates that the dynamic radar cruise control system is
unable to judge vehicle-to-vehicle distance
A buzzer also sounds.
→ Tu r n o f f s n o w m o d e .
If the windshield wipers are on, turn them off or set
them to a mode other than AUTO or high speed
wiper operation.
(If equipped)
Indicates that the LDA (Lane Departure Alert) system is
suspended (The camera sensor temperature is higher
than the operation temperature range)
A buzzer also sounds.
→ Restart the LDA after driving for a while.
(If equipped)
Indicates that a Blind Spot Monitor sensor or the sur-
rounding area on the bumper is dirty or covered with ice
A buzzer also sounds.
→ Clean the sensor and its surrounding area on the
bumper.
Wa r n i n g m e s s a g eDetails/Actions
Page 557 of 612

5578-2. Steps to take in an emergency
8
When trouble arises
IS200t_EE(OM53D19E)
●The needle of the engine coolant temperature gauge (→P. 95) enters the red
zone or a loss of engine power is experienced. (For example, the vehicle
speed does not increase.)
●“Engine Coolant High Temperature” is shown on the multi-information dis-
play.
●Steam comes out 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,
immediately contact any authorized
Lexus dealer or repairer, or another
duly qualified and equipped profes-
sional.
If your vehicle overheats
The following may indicate that your vehicle is overheating.
Correction procedures
1
2
3
1
2
Page 558 of 612
5588-2. Steps to take in an emergency
IS200t_EE(OM53D19E)
Engine coolant reservoir:
The coolant level is satisfactory if it is between the “FULL” and “LOW” lines on
the reservoir.Reservoir cap
“FULL” line
“LOW” line
Intercooler coolant reservoir:
The coolant level is satisfactory if it is between the “F” and “L” lines on the res-
ervoir. Reservoir cap
“F” line
“L” line
Add coolant if necessary.
Water can be used in an emergency if coolant is unavailable.
4
1
2
3
1
2
3
5
XEngine XIntercooler