Page 417 of 588
4177-3. Do-it-yourself maintenance
7
Maintenance and care
IS250_EE(OM53C51E)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 4 5 )
Battery (→P. 422)
Engine oil level dipstick
(→P. 4 1 8 )
Engine coolant reservoir
(→P. 4 2 1 )
Engine oil filler cap (→P. 4 1 9 )Wa s h e r f l u i d t a n k (→P. 4 2 6 )
Electric cooling fans
Condenser (→P. 422)
Radiator (→P. 422)1
2
3
4
5
6
7
8
9
Page 421 of 588

4217-3. Do-it-yourself maintenance
7
Maintenance and care
IS250_EE(OM53C51E)
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. 5 3 1 )
■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 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 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.
Engine coolant
1
2
3
CAUTION
■When the engine is hot
Do not remove the engine coolant reservoir cap or radiator cap. (→P. 5 3 1 )
The cooling system may be under pressure and may spray hot coolant if the cap is
removed, causing serious injuries, such as burns.
Page 422 of 588

4227-3. Do-it-yourself maintenance
IS250_EE(OM53C51E)
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 condi-
tion, have your vehicle inspected by any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
Check the battery as follows.
■Caution symbols
The meaning of each caution symbol on the top of the battery are as follows:
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 and condenser
CAUTION
■When the engine is hot
Do not touch the radiator or condenser as they may be hot and cause serious injuries,
such as burns.
Battery
No smoking, no naked
flames, no sparksBattery acid
Shield eyesNote operating instructions
Keep away from childrenExplosive gas
Page 474 of 588

4748-2. Steps to take in an emergency
IS250_EE(OM53C51E)
●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 485 of 588

4858-2. Steps to take in an emergency
8
When trouble arises
IS250_EE(OM53C51E)
Indicates a malfunction in the EPS (Electric Power Steer-
ing) system
A buzzer also sounds.
→Have the vehicle inspected by any authorized Lexus
dealer or repairer, or another duly qualified and
equipped professional.
Indicates that the vehicle is being driven at 5 km/h (3
mph) or more with the parking brake still engaged
A buzzer also sounds.
→Release the parking brake.
Indicates that the shift lever was used to attempt to shift
to the first gear position in M mode on a slippery road
surface
The gear position will not shift from the second gear.
A buzzer also sounds.
→Drive the vehicle in the second or a higher gear
position.
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.
→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 3 1
Wa r n i n g m e s s a g eDetails/Actions
(Flashes)
Page 531 of 588

5318-2. Steps to take in an emergency
8
When trouble arises
IS250_EE(OM53C51E)
●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.)
●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.
The coolant level is satisfactory if it is
between the “FULL” and “LOW”
lines on the reservoir.
Reser voir
“FULL”
“LOW”
If your vehicle overheats
The following may indicate that your vehicle is overheating.
Correction procedures
1
2
3
1
2
4
1
2
3
Page 532 of 588
5328-2. Steps to take in an emergency
IS250_EE(OM53C51E)
Add coolant if necessary.
Water can be used in an emergency if
coolant is unavailable.
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 authorized Lexus dealer or repairer,
or another duly qualified and equipped professional.
5
6
7
Page 533 of 588

5338-2. Steps to take in an emergency
8
When trouble arises
IS250_EE(OM53C51E)
CAUTION
■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.
NOTICE
■When adding engine coolant
Add coolant slowly after the engine has cooled down sufficiently. Adding cool coolant
to a hot engine too quickly can cause damage to the engine.
■To prevent damage to the cooling system
Observe the following precautions:
●Avoid contaminating the coolant with foreign matter (such as sand or dust etc.).
●Do not use any coolant additive.
●While the engine and radiator are hot, do not
loosen or remove the coolant reservoir cap
or radiator cap. (The radiator cap is located
under the engine cover.)
High temperature steam or coolant could
spray out.