cooling Lexus IS300h 2017 User Guide

5127-3. Do-it-yourself maintenance
IS300h_EE(OM53D89E)
WARNING
The engine compartment contains many mechanisms and fluids that may move suddenly, become hot, or become electrically energize d. To avoid death or serious injury, observe
the following precautions.
■When working on the engine compartment
●Make sure that the “ACCESSORY” or “I GNITION 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 flamma-
ble.
●Take care because brake fluid can harm yo ur 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 disc omfort, consult a doctor.
■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 elec tric cooling fans may automatically start to
run if the air conditioning is on and/ or the coolant temperature is high. (P. 521)
■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 f ilter 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 freq uent refilling, it may indicate a serious problem.

5157-3. Do-it-yourself maintenance
7
Maintenance and care
IS300h_EE(OM53D89E)
■12-volt battery
 P. 522
Engine compartment
Power control unit coolant reser-
voir ( P. 519)
Engine oil level dipstick
( P. 516)
Engine coolant reservoir
( P. 519)
Engine oil filler cap
( P. 517)
Fuse box ( P. 552)
Washer fluid tank ( P. 521)
Electric cooling fans
Condenser ( P. 521)
Power control unit coolant
radiator ( P. 521)
Engine coolant radiator
( P. 521)
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5207-3. Do-it-yourself maintenance
IS300h_EE(OM53D89E)
■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 retailer or Lexus autho-
rized repairer, or an y reliable repairer.
■If the coolant level drops within a short time of replenishing
Visually check the radiators, hoses, engine /power control unit coolant reservoir caps,
drain cock and water pump.
If you cannot find a leak, have any authorized Lexus retailer or Lexus authorized repairer, or any reliable repairer, test the cap an d check for leaks in the cooling system.
WARNING
■When the hybrid system is hot
Do not remove the engine/power control unit coolant reservoir caps or water filler cap. ( P. 636)
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.

6008-2. Steps to take in an emergency
IS300h_EE(OM53D89E)
Carrying out the corresponding action turns the messages off.
(If equipped)
Indicates that the PCS (Pre-Collision System) is tempo- rarily unavailable
 When conditions improve, the system resumes
operation. If this message is displayed continuously, have the vehicle inspected by any authorized Lexus
retailer or Lexus authorized repairer, or any reliable
repairer.
(If equipped)
Indicates that part of th e PCS (Pre-Collision System)
sensor is dirty, covered with ice, etc.
 Remove any dirt, ice, etc.
Other displayed messages
Warning messageDetails/Actions
(Flashes)
(Flashes)
Warning messageDetails/Actions
Maintenance of the hybrid battery (traction battery)
cooling component is required
The filter may be clogged, the air intake vent may be blocked or there may be a gap in the duct.
 Have maintenance performed on the hybrid battery
(traction battery) cooling component by any autho- rized Lexus retailer or Lexus authorized repairer, or
any reliable repairer.

6358-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D89E)
NOTICE
■When handling jumper cables
When connecting the jumper cables, ensure th at they do not become entangled in the
cooling fans or belt.
■Exclusive jump starting terminal
The exclusive jump starting terminal is inte nded to charge the 12-volt battery on your
vehicle from another vehicle in an emergency. Do not use the exclusive jump starting
terminal to jump start another vehicle.

6368-2. Steps to take in an emergency
IS300h_EE(OM53D89E)
●The needle of the engine coolant temperature gauge (P. 105) enters the
red zone or a loss of hybrid system po wer is experienced. (For example, the
vehicle speed does not increase.)
●“Engine Coolant Temp High Stop in a Safe Place See Owner’s Manual” or
“Hybrid System Overheated Reduced Ou tput Power” is shown on the multi-
information display.
●Steam comes out from under the hood.
■If the needle of the engine coolant temperature gauge enters the red zone
Stop the vehicle in a safe place and tu rn off the air conditioning system, and
then stop the hybrid system.
If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
After the hybrid system has
cooled down sufficiently, inspect
the hoses and radiator core (radi-
ator) for any leaks.
Radiator
Cooling fans
If a large amount of coolant leaks,
immediately contact any autho-
rized Lexus retailer or Lexus authorized repairer, or any reli-
able repairer.
If your vehicle overheats
The following may indicate that your vehicle is overheating.
Correction procedures
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6378-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D89E)
The coolant level is satisfactory if
it is between the “FULL” and
“LOW” lines on the reservoir.
Reservoir
“FULL”
“LOW”
Add coolant if necessary.
Water can be used in an emergency if 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 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, tu rn 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 immediatel y and contact any authorized Lexus
retailer or Lexus auth orized repairer, or any reliable repairer.
If the fans are operating:
Have the vehicle inspected at the nearest authorized Lexus retailer or
Lexus authorized repairer, or any reliable repairer.
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6388-2. Steps to take in an emergency
IS300h_EE(OM53D89E)
■If “Hybrid System Overheated Reduced Output Power” is shown on the
multi-information display
Stop the vehicle in a safe place.
Stop the hybrid system an d carefully lift the hood.
After the hybrid system has
cooled down, inspect the hoses
and radiator core (radiator) for
any leaks.
Radiator
Cooling fans
If a large amount of coolant leaks, immediately contact any autho-
rized Lexus retailer or Lexus
authorized repairer, or any reli- able repairer.
The coolant level is satisfactory if
it is between the “F” and “L” lines
on the reservoir.
Reservoir
“F”
“L”
Add coolant if necessary.
Water can be used in an emergency
if coolant is unavailable.
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6398-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D89E)
Start the hybrid system and check if “Hybrid System Overheated Reduced
Output Power” is shown on the multi-information display.
If the message does not disappear:
Stop the hybrid system and contact an y authorized Lexus retailer or Lexus
authorized repairer, or any reliable repairer.
If the message is not displayed:
Have the vehicle inspected at the nearest authorized Lexus retailer or
Lexus authorized repairer, or any reliable repairer.
WARNING
■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.
●After the hybrid system has been turned off, check that the “READY” indicator is off.
When the hybrid system operating, the gasoline engine may automatically start, or
the cooling fan may suddenly operate even if the gasoline engine stops. Do not touch or approach rotating parts such as the be lt and fan, which may lead to fingers or
clothing (especially a tie, a scarf or a mu ffler) getting caught, resulting in serious
injury.
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●Do not loosen the c oolant reservoir caps or
water filler cap while th e hybrid system and
radiator are hot. High temperature steam or coolant could
spray out.

6408-2. Steps to take in an emergency
IS300h_EE(OM53D89E)
NOTICE
■When adding engine/power control unit coolant
Add coolant slowly after the hybrid system has cooled down sufficiently. Adding cool
coolant to a hot hybrid syst em too quickly can cause damage to the hybrid system.
■To prevent damage to the cooling system
Observe the following precautions:
●Avoid contaminating the coolant with foreig n matter (such as sand or dust etc.).
●Do not use any coolant additive.