brake Lexus GS300h 2017 Repair Manual

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 modelsF SPORT models
3

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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)
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5
6
7

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

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)

4627-2. Steps to take in an emergency
GS450h_300h_OM_OM30F92E_(EE)
(Flashes)
(If equipped)
“AFS OFF” indicator
Indicates a malfunction in the adaptive front-lighting system
 Have the vehicle inspected by an y authorized Lexus retailer or
Lexus authorized repairer, or any reliable repairer immediately.
(Flashes)
Brake hold operated indicator Indicates a malfunction in the brake hold system
 Have the vehicle inspected by an y authorized Lexus retailer or
Lexus authorized repairer, or any reliable repairer immediately.
(Flashes)
Parking brake indicator Indicates a malfunction in the parking brake system
 Have the vehicle inspected by an y authorized Lexus retailer or
Lexus authorized repairer, or any reliable repairer immediately.
Brake system warning light Indicates a malfunction in:

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7-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30F92E_(EE)
WARNING
■If both the ABS and the brake system warning lights remain on
Stop your vehicle in a safe place immediately and contact any authorized Lexus retailer
or Lexus authorized repairer, or any reliable repairer. The vehicle will become
extremely unstable during braking, and the ABS system may fail, which could cause an
accident resulting in death or serious injury.
■When the electric power steering system warning light comes on
The steering wheel may become extremely heavy.
If the steering wheel becomes heavier than us ual when operating, hold firmly and oper-
ate using more force than usual.
■If the tire pressure warning light comes on
Be sure to observe the following precautions. Failure to do so could cause a loss of
vehicle control and result in death or serious injury.
●Stop your vehicle in a safe place as soon as possible. Adjust the tire inflation pressure
immediately.
●If the tire pressure warning light comes on even after tire inflation pressure adjust-
ment, it is probable that you have a flat tire. Check the tires. If a tire is flat, change it
with the spare tire and have the flat tire repaired by the nearest any authorized Lexus
retailer or Lexus authorized repa irer, or any reliable repairer.
●Avoid abrupt maneuvering and braking. If the vehicle tires deteriorate, you could lose
control of the steering wheel or the brakes.
■If a blowout or sudden air leakage should occur
The tire pressure warning system may not activate immediately.
NOTICE
■To ensure the tire pressure warning system operates properly
Do not install tires with different specifications or makers, as the tire pressure warning
system may not operate properly.

4667-2. Steps to take in an emergency
GS450h_300h_OM_OM30F92E_(EE)
If a warning message is displayed
Master warning light
The master warning light also comes on or flashes in order to indicate that a message
is currently being displayed on the multi-information display.
Multi-information display
If any of the warning light comes on again after the following actions have been
performed, contact any authorized Lexus retailer or Lexus authorized repairer,
or any reliable repairer.
If a warning is shown on the multi-information display, stay calm and perform
the following actions:
Except F SPORT modelsF SPORT models
Warning message and warning buzzer list
1
2
Warning messageDetails/Actions
(If equipped)
Indicates that there is a high possibility of a frontal colli-
sion, or that the pre-crash braking function is operating
At the same time, will appear on the head-
up display.
A buzzer also sounds.
 Avoid the collision by decelerating using the brakes
or taking other evasive actions.

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7-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30F92E_(EE)
(If equipped)
Indicates that your vehicle is nearing the vehicle ahead
(in vehicle-to-vehicle distance control mode)
At the same time, will appear on the head-up dis-
play (the image flashes).
A buzzer also sounds.
 Slow the vehicle by applying the brakes.
(If equipped)
Indicates that the vehicle has deviated from the lane
(while the LKA [Lane-Keeping Assist] system is operat-ing)
The lane line on the side the vehicle has deviated from
flashes in amber.
At the same time, will appear on the head-
up display (the image flashes).
A buzzer also sounds.
 Check around the vehicle and back to inside of the
lane lines.
Indicates a malfunctio n in the brake system
A buzzer also sounds.
 Have the vehicle inspected by any authorized Lexus
retailer or Lexus authorized repairer, or any reliable
repairer.
Continuing to drive the vehicle may be dangerous.
Warning messageDetails/Actions
(Flashes)

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7-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30F92E_(EE)
(If equipped)
Indicates a malfunction in the Lexus parking assist
All assist-sensors flash.
A buzzer also sounds.
 Have the vehicle inspected by any authorized Lexus
retailer or Lexus authorized repairer, or any reliable
repairer.
(If equipped)
Indicates that Lexus parking a ssist-sensor is dirty or cov-
ered with ice
A buzzer also sounds.
 Clean the sensor.
Indicates an attempt was made to release the parking
brake with a door open or the front passenger’s seat belt
unfastened
A buzzer also sounds.
 Close all doors and fasten the front passenger’s seat
belt before releasing the parking brake.
Warning messageDetails/Actions
(Flashes)

4727-2. Steps to take in an emergency
GS450h_300h_OM_OM30F92E_(EE)
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 parking brake is engaged with the shift
position not in P
A buzzer also sounds.
 Change the shift position to P.
Indicates a malfunction in the brake hold system
A buzzer also sounds.
 Depress the brake pedal to turn off the brake hold
system.
Have the vehicle inspected by any authorized Lexus
retailer or Lexus authorized repairer, or any reliable
repairer.
Indicates that the brake hold system is turned on while on
a steep slope A buzzer also sounds.
 Do not use only the brake hold system on steep
slopes. Be sure to also depress the brake pedal.
Indicates a malfunction in the parking brake system
A buzzer also sounds.
 Press the parking brake switch. If the warning mes-
sage is still displayed, have the vehicle inspected by
any authorized Lexus retailer or Lexus authorized
repairer, or any reliable repairer.
Warning messageDetails/Actions
(Flashes)
(Flashes)
(Flashes) (Flashes)