2014 Lexus GS450h engine overheat

TABLE OF CONTENTS6
GS450h_OM_OM30D52U_(U)
6-3. Do-it-yourself maintenanceDo-it-yourself service precautions.................................657
Hood ............................................... 660
Positioning a floor jack............... 661
Engine compartment ............... 663
12-volt battery ..............................673
Tires................................................... 677
Tire inflation pressure ............... 687
Wheels ........................................... 690
Air conditioning filter ............... 692
Electronic key battery.............. 694
Checking and replacing fuses.............................................. 696
Headlight aim ................................. 711
Light bulbs ......................................713
7-1. Essential information Emergency flashers .................. 728
If your vehicle has to be stopped in an emergency.....729 7-2. Steps to take in an emergency
If your vehicle needs to be towed................................ 730
If you think something is wrong .................736
If a warning light turns on or a warning buzzer sounds...... 737
If a warning message is displayed ................................. 747
If you have a flat tire ...................775
If the hybrid system will not start ............................... 788
If the shift lever cannot be shifted from P ..................... 790
If the parking brake cannot be released .................................. 791
If the electronic key does not operate properly ......................793
If the 12-volt battery is discharged..............................796
If your vehicle overheats ........ 800
If the vehicle becomes stuck .............................................805
7When trouble arises
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17Pictorial index
GS450h_OM_OM30D52U_(U)
Windshield wipers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 223
Precautions against winter season . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 342
To prevent freezing (windshield wiper de-icer)
* . . . . . . . . . . . . . . . . . . . . .P. 410
Precautions against car wash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 644
Fuel filler door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 2 3 1
Refueling method. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 231
Fuel type/fuel tank capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 810
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 677
Tire size/inflation pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 816
Winter tires/tire chain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 342
Checking/rotation/tire pressure warning system. . . . . . . . . . . . . . . . . . . . P. 677
Coping with flat tires. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 775
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 660
Opening . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 660
Engine compartment cover. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 664
Engine oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 811
Coping with overheat. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 800
Warning messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 754
Headlights/parking lights/daytime running lights . . . . . . . . . . . . . . . . . . . P. 217
Fog lights
* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 222
Turn signal lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 209
Tail lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 217
Stop lights
Brake Hold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P . 214
License plate lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 21 7
Back-up lights
Shifting the shift lever to R . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 203
Side marker lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 21 7
4
5
6
7
Light bulbs of the exterior lights for driving
(Replacing method: P. 713, Watts: P. 817)
*: If equipped
8
9
10
11
12
13
14
15
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GS450h_OM_OM30D52U_(U)
952. Instrument cluster
2
Instrument cluster
■ECO lamp and SPORT lamp
●When sport mode is selected, SPORT lamp (red) will illuminate.
●When all of the following conditions are satisfied and Eco-friendly driving, ECO
lamp (blue) will illuminate. (ECO lamp will become brighter the more Eco-friendly
driving you perform. Also, while the vehicle is stopped or the acceleration exceeds
Zone of Eco driving, ECO lamp turns off. [→P. 94] However, when Eco drive
mode is selected, while the vehicle is stopped or the acceleration exceeds Zone of
Eco driving, ECO lamp does not turn off.):
• Driving with the shift lever in D
• Paddle shift switch is not operated.
• Either normal mode or Eco drive mode is selected.
• The vehicle speed is approximately 80 mph (130 km/h) or below.
■Tachometer
Hybrid System Indicator switches to the tachometer when driving mode is in sport
mode.
■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 vehi-
cle operation and driving conditions are the same.
■Customization
Settings (e.g. on/off operation of ECO lamp) can be changed.
(Customizable features: → P. 8 3 3 )
NOTICE
■To prevent damage to the engine and its components
●Do not let the indicator needle of the tachometer enter the red zone, which indi-
cates 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. 800)
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4-1. Before driving
CAUTION
Observe the following precautions.
Failure to do so may result in death or serious injury.
■When driving the vehicle
●During normal driving, do not turn off the hybrid system. Turning the hybrid sys-
tem 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. 7 2 9
●Use engine braking (downshift) to maintain a safe speed when driving down a
steep hill.
Using the brakes continuously may cause the brakes to overheat and lose effec-
tiveness. ( →P. 2 0 3 )
●Do not adjust the positions of the steering wheel, the seat, or the inside or outside
rear view mirrors while driving.
Doing so may result in a loss of vehicle control.
●Always check that all passengers’ arms, heads or other parts of their body are not
outside the vehicle.
●Do not drive in excess of the speed limit. Even if the legal speed limit permits it, do
not drive over 85 mph (140 km/h) unless your vehicle has high-speed capability
tires. Driving over 85 mph (140 km/h) may result in tire failure, loss of control and
possible injury. Be sure to consult a tire dealer to determine whether the tires on
your vehicle are high-speed capability tires or not before driving at such speeds.
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4-1. Before driving
CAUTION
■If you hear a squealing or scraping noise (brake pad wear limit indicators)
Have the brake pads checked and replaced by your Lexus dealer as soon as possi-
ble.
Rotor damage may result if the pads are not replaced when needed.
Front brakes only: Moderate levels of brake pad and disc wear allow enhanced
front braking power. As a result, the discs may wear more quickly than conven-
tional brake discs. Therefore, when replacing the brake pads, Lexus recommends
that you also have the thickness of the discs measured.
It is dangerous to drive the vehicle when the wear limits of the brake pads and/or
those of the brake discs are exceeded.
■When the vehicle is stopped
●Do not depress the accelerator pedal unnecessarily.
If the vehicle is in any gear other than P or N, the vehicle may accelerate suddenly
and unexpectedly, causing an accident.
●In order to prevent accidents due to the vehicle rolling away, always keep
depressing the brake pedal while the “READY” indicator is on, 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 racing 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.
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4-5. Using the driving support systems
■When the message is displayed on the multi-information display showing that
TRAC has been disabled even if the VSC OFF switch has not been pressed
TRAC cannot be operated. Contact your Lexus dealer.
■Sounds and vibrations caused by the ABS, brake assist, VSC and TRAC systems
●A sound may be heard from the engine compartment when the brake pedal is
depressed repeatedly, when the hybrid system is started or just after the vehicle
begins to move. This sound does not indicate that a malfunction has occurred in
any of these systems.
●Any of the following conditions may occur when the above systems are operating.
None of these indicates that a malfunction has occurred.
• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard after the vehicle comes to a stop.
■EPS operation sound
When the steering wheel is operated, a motor sound (whirring sound) may be heard.
This does not indicate a malfunction.
■Reactivation of the TRAC/VSC systems
Even after the TRAC/VSC systems have been turned off, turning the hybrid system
off and then on again will automatically reactivate the TRAC/VSC systems.
■Reactivation of the TRAC system linked to vehicle speed
When only the TRAC system is turned off, the TRAC system will turn on when vehi-
cle speed increases. However, when both TRAC/VSC systems are turned off, the
systems will not turn on even when vehicle speed increases.
■Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the system from overheat-
ing when there is frequent steering input over an extended period of time. The steer-
ing wheel may feel heavy as a result.
* Should this occur, refrain from excessive
steering input or stop the vehicle and turn the hybrid system off. The EPS system
should return to normal within 10 minutes.
*: If the LKA (Lane-Keeping Assist) system cannot operate in this case, a warning
message will be shown on the multi-information display.
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7627-2. Steps to take in an emergency
GS450h_OM_OM30D52U_(U)
Indicates that the LKA
(Lane-Keeping Assist)
system detects no-
handed driving (while the
lane keeping assist func-
tion is operating)The warning buzzer
sounds twice.
Grip the steering wheel
firmly.
Indicates that the Blind
Spot Monitor sensors or
the surrounding area on
the bumper is dirty or
covered with ice
Clean the sensor and its
surrounding area on the
bumper.
Indicates that the hybrid
system has overheatedThis message may be
displayed when driving
under severe operating
conditions. (For exam-
ple, when driving up a
long steep hill.)
Stop and check.
(→ P. 800)
Indicates that the hybrid
system output is limited
because the engine oil is
overheatedDrive the vehicle at a safe
speed until the warning
message disappears.
Warning messageDetailsCorrection procedure
(If equipped)
(If equipped)
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800
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7-2. Steps to take in an emergency
If your vehicle overheats
■If the needle of the engine coolant temperature gauge enters the red
zone
Stop the vehicle in a safe place and turn off the air conditioning sys-
tem, 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 cooling system for leaks.
Radiator
Cooling fans
If a large amount of coolant
leaks, immediately contact your
Lexus dealer.
The following may indicate that your vehicle is overheating.
●The needle of the engine coolant temperature gauge ( →P. 91) enters
the red zone or a loss of hybrid system power is experienced. (For
example, the vehicle speed does not increase.)
●“Hybrid System Overheat” ( →P. 762) is shown on the multi-informa-
tion display.
●Steam comes out from under the hood.
Correction procedures
1
2
3
1
2
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