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3986-2. Maintenance
GS450h_300h_OM_OM30F92E_(EE)
■Does your vehicle need repairs?
Be on the alert for changes in performance and sounds, and visual tip-offs that indicate
service is needed. Some important clues are:
●Engine missing, stumbling or pinging
●Appreciable loss of power
●Strange engine noises
●A fluid leak under the vehicle (However, water dripping from the air conditioning sys-
tem after use is normal.)
●Change in exhaust sound (This may indicate a dangerous carbon monoxide leak. Drive
with the windows open and have the exhaust system checked immediately.)
●Flat-looking tires, excessive tire sque al when cornering, uneven tire wear
●Vehicle pulls to one side when driven straight on a level road
●Strange noises related to suspension movement
●Loss of brake effectiveness, spongy feeling brake pedal, pedal almost touches the floor,
vehicle pulls to one side when braking
●Engine coolant temperature continually higher than normal ( P. 105)
If you notice any of these clues, take your vehicle to any authorized Lexus retailer or
Lexus authorized repairer, or any reliable repairer as soon as possible. Your vehicle may
need adjustment or repair.
WARNING
■If your vehicle is not properly maintained
Improper maintenance could result in serious damage to the vehicle and possible
death or serious injury.
■Handling of the 12-volt battery
12-volt battery posts, terminals and related accessories contain lead and lead com-
pounds which are known to cause brain damage. Wash your hands after handling. ( P. 412)
Page 400 of 600
4006-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30F92E_(EE)
WARNING
The engine compartment contains many mech anisms 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 “POWER 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 co ntrol 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 your hands or eyes and damage painted sur-
faces. If fluid gets on your hands or in your eyes, flush t he 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 power switch is off.
With the power switch in ON mode, the electric cooling fans may automatically start to
run if the air conditioning is on and/or the coolant temperature is high. ( P. 411)
■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 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 refillin g, it may indicate a serious problem.
Page 451 of 600
451
7When trouble arises
GS450h_300h_OM_OM30F92E_(EE) 7-1. Essential information
Emergency flashers ..................452
If your vehicle has to be stopped in an
emergency.................................453 7-2. Steps to take in an
emergency
If your vehicle needs to be towed................................ 454
If you think something is wrong....................................... 459
If a warning light turns on or a warning buzzer
sounds..........................................460
If a warning message is displayed ................................ 466
If you have a flat tire (vehicles with spare tire) ......498
If you have a flat tire (vehicles without spare
tire)................................................509
If the hybrid system will not start................................ 523
If the parking brake cannot be released................. 525
If the electronic key does not operate properly ............. 527
If the 12-volt battery is discharged .................................530
If your vehicle overheats .........535
If the vehicle becomes stuck ............................................. 542
Page 453 of 600
453
7
7-1. Essential information
When trouble arises
GS450h_300h_OM_OM30F92E_(EE)
If your vehicle has to be stopped in an emergency
Steadily step on the brake pedal with both feet and firmly depress it.
Do not pump the brake pedal repeatedly as this will increase the effort required to
slow the vehicle.
Shift the shift lever to N.
If the shift lever is shifted to N
After slowing down, stop the vehicle in a safe place by the road.
Stop the hybrid system.
If the shift lever cannot be shifted to N
Keep depressing the brake pedal with both feet to reduce vehicle speed as
much as possible.
To stop the hybrid system, press and
hold the power switch for 2 consec-
utive seconds or more, or press it
briefly 3 times or more in succes-
sion.
Stop the vehicle in a safe place by the road.
Only in an emergency, such as if it becomes impossible to stop the vehicle in
the normal way, stop the vehicl e using the following procedure:
1
2
3
4
3
Press and hold for 2 seconds or more
or press briefly 3 times or more
4
WARNING
■If the hybrid system has to be turned off while driving
Power assist for the steering wheel will be lost, making the steering wheel heavier to
turn. Decelerate as much as possible before turning off the hybrid system.
5
Page 456 of 600
4567-2. Steps to take in an emergency
GS450h_300h_OM_OM30F92E_(EE) If a tow truck is not available in an emergency, your vehicle may be temporarily
towed using cables or chains secured to the emergency towing eyelets. This
should only be attempted on hard surfaced roads for short distances at under
30 km/h (18 mph).
A driver must be in the vehicle to steer and operate the brakes. The vehicle’s
wheels, drive train, axles, steering and brakes must be in good condition.
Take out the towing eyelet. ( P. 499, 511)
Remove the eyelet cover using a flathead screwdriver.
To protect the bodywork, place a rag between the screwdriver and the vehicle body
as shown in the illustration.
Insert the towing eyelet into the hole
and tighten partially by hand.
Emergency towing
Emergency towing procedure
1
2
Except F SPORT modelsF SPORT models
3
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457
7-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30F92E_(EE) Tighten down the towing eyelet
securely using a wheel nut wrench
or hard metal bar.
Securely attach cables or chains to the towing eyelet.
Take care not to damage the vehicle body.
Enter the vehicle being towed and start the hybrid system.
If the hybrid system does not start,
turn the power switch to ON mode.
Shift the shift lever to N and release the parking brake.
When the shift lever cannot be shifted: P. 229
■While towing
If the hybrid system is off, the power assist for the brakes and steering will not function,
making steering and braking more difficult.
■Wheel nut wrench
Wheel nut wrench is installed in trunk. ( P. 499, 511)
4
5
6
7
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459
7
7-2. Steps to take in an emergency
When trouble arises
GS450h_300h_OM_OM30F92E_(EE)
If you think something is wrong
●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 hybrid system
● 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 notice any of the following sy mptoms, your vehicle probably needs
adjustment or repair. Contact any authorized Lexus retailer or Lexus autho-
rized repairer, or any reliable repairer as soon as possible.
Visible symptoms
Audible symptoms
Operational symptoms
Page 460 of 600
4607-2. Steps to take in an emergency
GS450h_300h_OM_OM30F92E_(EE)
If a warning light turns on or a warning buzzer
sounds
Calmly perform the following actions if any of the warning lights comes on or
flashes. If a light comes on or flashes, but then goes off, this does not necessar-
ily indicate a malfunction in the system. However, if this continues to occur,
have the vehicle inspected by any authorized Lexus retailer or Lexus autho-
rized repairer, or any reliable repairer.
Warning light and warning buzzer list
Warning lightWarning light/Details/Actions
Brake system warning light (warning buzzer)
