2017 Lexus IS300h engine overheat

15Pictorial index
IS300h_EE(OM53D89E)
Windshield wipers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 245
Precautions against winter season . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 361
To prevent freezing (windshield wiper de-icer)*1 . . . . . . . . . . . . . . . . . . . . . . P. 475
Precautions against car wash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 504
Fuel filler door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P . 253
Refueling method. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 253
Fuel type/fuel tank capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 646
Tires. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 525
Tire size/inflation pressure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 652
Winter tires/tire chain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 361
Checking/rotation/tire pressure warning system . . . . . . . . . . . . . . . . . . . . . . P. 525 Coping with flat tires. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 610, 625
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 513
Opening . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 513 Engine oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 647
Coping with overheat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 636
Warning messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 584
Headlights/front position li ghts/daytime running lights . . . . . . . . . . . P. 237
Turn signal lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 2 33
Tail lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 237
Stop lights
Emergency brake signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 353
Rear fog light*3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 244
Back up light*2
Shifting the shift lever to R . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 226
Rear fog light*2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 244
Back up light*3
Shifting the shift lever to R . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 226
License plate lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 237
4
5
6
7
Light bulbs of the exte rior lights for driving
(Replacing method: P. 556, Watts: P. 654)
*1: If equipped
*2: Left-hand drive vehicles
*3: Right-hand drive vehicles
8
9
10
11
12
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1102. Instrument cluster
IS300h_EE(OM53D89E)
■Tachometer
Hybrid System Indicator switches to the tachometer when driving mode is in sport mode.
The settings of the tachometer display can be changed on the multi-information display.
( P. 119)
■Engine speed
On hybrid vehicles, engine speed is precisely controlled in order to help improve fuel
efficiency and reduce exhaust emissions etc.
There are times when the engine speed that is displayed may differ even when vehicle operation and driving conditions are the same.
■Outside temperature display
In the following situations, the correct outside temperature may not be displayed, or the display may take longer than normal to change.
●When stopped, or driving at low sp eeds (less than 20 km/h [12 mph])
●When the outside temperature has changed suddenly (at the entrance/exit of a garage, tunnel, etc.)
■Pop-up display
●In some situations, such as when a switch operation is performed, a pop-up display will be temporarily displayed on the multi-info rmation display or the odometer/trip meter
screen (F SPORT models).
●Some pop-up displays can be set on/off. ( P. 119)
■Customization
The meter display can be customized on the multi-information display. (P. 119)
NOTICE
■To prevent damage to the engine and its components
●Do not let the indicator needle of the tachometer enter the red zone, which indicates
the maximum engine speed.
●The engine may be overheating if the engine coolant temperature gauge is in the red zone (H). In this case, immediately stop the vehicle in a safe place, and check the
engine after it has cooled completely. ( P. 636)

2044-1. Before driving
IS300h_EE(OM53D89E)
■Drum-in-disc type parking brake system
Your vehicle has a drum-in-disc type parkin g brake system. This type of brake system needs bedding-down of the brake shoes peri odically or whenever the parking brake
shoes and/or drum are replaced. Have any au thorized Lexus retailer or Lexus authorized
repairer, or any reliable repairer, perform the bedding down operation.
■Operating your vehicle in a foreign country
Comply with the relevant vehi cle registration laws and confirm the availability of the cor-
rect fuel. ( P. 646)
WARNING
Observe the following precautions.
Failure to do so may result in death or serious injury.
■When starting the vehicle
Always keep your foot on the brake pedal while stopped with the “READY” indicator is
illuminated. This prevents the vehicle from creeping.
■When driving the vehicle
●Do not drive if you are unfamiliar with the location of the brake and accelerator ped-
als to avoid depressing the wrong pedal.
• Accidentally depressing the accelerator pedal instead of the brake pedal will result in sudden acceleration that may lead to an accident.
• When backing up, you may twist your body around, leading to a difficulty in oper-
ating the pedals. Make sure to operate the pedals properly. • Make sure to keep a correct driving po sture even when moving the vehicle only
slightly. This allows you to depress the brake and accelerator pedals properly.
• Depress the brake pedal using your right foot. Depressing the brake pedal using your left foot may delay re sponse in an emergency, resulting in an accident.
●The driver should pay extra attention to pedestrians when the vehicle is powered only by the electric motor (traction motor). As there is no engine noise, the pedestrians
may misjudge the v ehicle’s movement.
●Do not drive the vehicle over or stop the vehicle near flammable materials. The exhaust system and exhaust gases can be extremely hot. These hot parts may
cause a fire if there is any flammable material nearby.
●During normal driving, do not turn off the hybrid system. Turning the hybrid system off while driving will not cause loss of steering or braking control, however, power assist
to the steering will be lost. This will make it more difficult to steer smoothly, so you
should pull over and stop the vehicle as soon as it is safe to do so. In the event of an emergency, such as if it becomes impossible to stop the vehicle in
the normal way: P. 567
●Use engine braking (downshift) to maintain a safe speed when driving down a steep hill.
Using the brakes continuously may cause th e brakes to overheat and lose effective-
ness. ( P. 226)

2064-1. Before driving
IS300h_EE(OM53D89E)
WARNING
Observe the following precautions. Failure to do so may result in death or serious injury.
■When the vehicle is stopped
●Do not depress the accelerator pedal unnecessarily.If the shift lever is in any position other than P or N, the vehicle may accelerate sud-
denly and unexpectedly, causing an accident.
●In order to prevent accidents due to the ve hicle rolling away, always keep depressing the brake pedal while stopped with the “REA DY” indicator is illuminated, and apply
the parking brake as necessary.
●If the vehicle is stopped on an incline, in order to prevent accidents caused by the vehicle rolling forward or backward, always depress the brake pedal and securely
apply the parking brake as needed.
●Avoid revving or r acing the engine. Running the engine at high speed while the vehicle is stopped may cause the exhaust
system to overheat, which could result in a fire if combustible material is nearby.
■When the vehicle is parked
●Do not leave glasses, cigarette lighters, spray cans, or soft drink cans in the vehicle
when it is in the sun.
Doing so may result in the following:
• Gas may leak from a cigarette lighter or spray can, and may lead to a fire.
• The temperature inside the vehicle may ca use the plastic lenses and plastic mate-
rial of glasses to deform or crack. • Soft drink cans may fracture, causing the contents to spray over the interior of the
vehicle, and may also cause a short circui t in the vehicle’s electrical components.
●Do not leave cigarette lighters in the vehicle. If a cigarette lighter is in a place such as
the glove box or on the floor, it may be lit accidentally when luggage is loaded or the
seat is adjusted, causing a fire.
●Do not attach adhesive discs to the windshield or windows. Do not place containers
such as air fresheners on the instrument panel or dashboard. Adhesive discs or con-
tainers may act as lenses, causing a fire in the vehicle.
●Do not leave a door or window open if th e curved glass is coated with a metallized
film such as a silver-colored one. Reflecte d sunlight may cause the glass to act as a
lens, causing a fire.
●Always apply the parking brake, shift the shift lever to P, stop the hybrid system and
lock the vehicle.
Do not leave the vehicle unattended whil e the “READY” indicator is illuminated. If the vehicle is parked with the shift leve r in P but the parking brake is not set, the
vehicle may start to move, possibly leading to an accident.
●Do not touch the exhaust pipes while the “R EADY” indicator is illuminated or imme-
diately after turning the hybrid system off. Doing so may cause burns.

2174-1. Before driving
4
Driving
IS300h_EE(OM53D89E)
■Important points regarding stability
Vehicle movement resulting from unev en road surfaces and strong cross-
winds will affect handling. The vehicle ma y also be rocked by passing buses or
large trucks. Frequently check behind when moving alongside such vehicles.
As soon as such vehicle movement o ccurs, immediately start to decelerate
smoothly by slowly applying the brakes. Always steer the vehicle straight
ahead while braking.
■Passing other vehicles
Consider the total combined length of your vehicle and trailer and ensure that
the vehicle-to-vehicle distance is su fficient before executing lane changes.
■Transmission information
To maintain engine braking efficiency, when using engine braking when driv-
ing on a long steep downward grade, do not use the transmission in D. The
vehicle must be driven in gear shift position “4” in S mode. (P. 229)
■If the engine overheats
Towing a loaded trailer up a long, steep incline in temperatures exceeding
30 C (85F) may result in the engine overheating. If the engine coolant tem-
perature gauge indicates that the engine is overheating, turn the air condition-
ing off immediately, leave the road and stop the vehicle in a safe place.
( P. 636)
■When parking the vehicle
Always place wheel chocks under the wheels of both the vehicle and trailer.
Firmly set the parking brake an d shift the shift lever to P.

5968-2. Steps to take in an emergency
IS300h_EE(OM53D89E)
Indicates a malfunction in the brake override system
A buzzer also sounds.
 Have the vehicle inspected by any authorized Lexus retailer or Lexus authorized repairer, or any reliable
repairer.
Indicates that engine oil level is low
This message may ap pear if the vehicle is stopped on a
slope. Move the vehicle to a level surface and check to see if the message disappears.
 Check the level of engine oil, and add if necessary.
Indicates that the hybrid system has overheated This message may be disp layed when driving under
severe operating conditions. (For example, when driv-
ing up a long steep hill.) A buzzer also sounds.
 Stop and check. (P. 636)
Indicates a malfunction in:
• The automatic headlight leveling system; or • The Automatic High Beam system (if equipped); or
• The LED headlight system
A buzzer also sounds.  Have the vehicle inspected by any authorized Lexus
retailer or Lexus authorized repairer, or any reliable
repairer.
Warning messageDetails/Actions

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
1
2
3
1
2

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.
6
●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.