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GS450h_OM_OM30D52U_(U)
6856-3. Do-it-yourself maintenance
6
Maintenance and care
CAUTION
■When inspecting or replacing tires
Observe the following precautions to prevent accidents.
Failure to do so may cause damage to parts of the drive train as well as dangerous
handling characteristics, which may lead to an accident resulting in death or seri-
ous injury.
●Do not mix tires of different makes, models or tread patterns.
Also, do not mix tires of remarkably different treadwear.
●Do not use tire sizes other than those recommended by Lexus.
●Do not mix differently constructed tires (radial, bias-belted or bias-ply tires).
●Do not mix summer, all season and snow tires.
●Do not use tires that have been used on another vehicle.
Do not use tires if you do not know how they were used previously.
■When initializing the tire pressure warning system
Do not operate the tire pressure warning reset switch without first adjusting the tire
inflation pressure to the specified level. Otherwise, the tire pressure warning light
may not come on even if the tire inflation pressure is low, or it may come on when
the tire inflation pressure is actually normal.
■Caution regarding interference with electronic devices (vehicles with the tire
inflation pressure display function)
●Users of any electrical medical device other than implantable cardiac pacemak-
ers, cardiac resynchronization therapy-pacemakers or implantable cardioverter
defibrillators should consult the manufacturer of the device for information about
its operation under the influence of radio waves.
Radio waves could have unexpected effects on the operation of such medical
devices.
●People with implantable cardiac pacemak-
ers, cardiac resynchronization therapy-
pacemakers or implantable cardioverter
defibrillators should not come within 17.7 in.
(450 mm) of the tire pressure warning sys-
tem initiators. The radio waves may affect
the operation of such devices.
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7417-2. Steps to take in an emergency
GS450h_OM_OM30D52U_(U)
7
When trouble arises
*1: Open door warning buzzer:→ P. 7 5 4
*2: Driver’s seat belt buzzer:
The driver’s seat belt buzzer sounds to alert the driver that his or her seat belt is
not fastened. Once the power switch is turned to ON mode, the buzzer sounds
for 6 seconds. If the vehicle reaches a speed of 12 mph (20 km/h), the buzzer
sounds once. If the seat belt is still unfastened after 24 seconds, the buzzer will
sound intermittently for 10 seconds. Then, if the seat belt is still unfastened, the
buzzer will sound in a different tone for 20 more seconds.
Front passenger’s seat belt buzzer:
The front passenger’s seat belt buzzer sounds to alert the front passenger that his
or her seat belt is not fastened. The buzzer sounds once if the vehicle reaches a
speed of 12 mph (20 km/h). If the seat belt is still unfastened after 24 seconds, the
buzzer will sound intermittently for 10 seconds. Then, if the seat belt is still unfas-
tened, the buzzer will sound in a different tone for 20 more seconds.
Tire pressure warning light
When the light comes on:
Low tire inflation pressure such
as • Natural causes ( →P. 74 3 )
• Flat tire ( →P. 7 7 5 )
Adjust the tire inflation pressure
to the specified level.
The light will turn off after a
few minutes. In case the light
does not turn off even if the
tire inflation pressure is
adjusted, have the system
checked by your Lexus
dealer.
When the light comes on after
blinking for 1 minute:
Malfunction in the tire pressure
warning system
Have the system checked by
your Lexus dealer.
Warning lightWarning light/DetailsCorrection procedure
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7597-2. Steps to take in an emergency
GS450h_OM_OM30D52U_(U)
7
When trouble arises
*: For the EV drive mode operating conditions: →P. 2 0 0
Indicates that the EV
drive mode is not avail-
able
*
The reason the EV
drive mode is not avail-
able (the vehicle is
idling, battery charge is
low, speed is higher
than the EV drive
mode operating speed
range, accelerator
pedal is depressed too
much) may be dis-
played.
Use the EV drive mode
when it becomes avail-
able.
Indicates that the EV
drive mode has been
automatically canceled
*
The reason the EV
drive mode is not avail-
able (the battery
charge is low, speed is
higher than the EV
drive mode operating
speed range, accelera-
tor pedal is depressed
too much) may be dis-
played.
Drive the vehicle for a
while.
Indicates that engine oil
level is lowCheck the level of engine
oil, and add if necessary.
Warning messageDetailsCorrection procedure
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7647-2. Steps to take in an emergency
GS450h_OM_OM30D52U_(U)
■Warning message in radar cruise mode (if equipped)
In the following cases, the warning message may not be displayed even if vehicle-to-
vehicle distance decreases:
●When your vehicle and the vehicle ahead are traveling at the same speed or the
vehicle ahead is traveling more quickly than your vehicle
●When the vehicle ahead is traveling at a very low speed
●Immediately after cruise control speed is set
●At the instant the accelerator pedal is depressed
■The LKA (Lane-Keeping Assist) lane departure warning function
In the following cases, the warning message will not be displayed even if a lane line is
crossed.
●When the vehicle speed deviates from the operating range of the LKA system
functions
●When the lane lines cannot be recognized
●When the steering wheel is turned as far as necessary to cause the vehicle to
change lanes
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7737-2. Steps to take in an emergency
GS450h_OM_OM30D52U_(U)
7
When trouble arises
InteriorbuzzerExterior
buzzerWarning messageDetailsCorrection procedure
Once
The driver’s door
was opened and
closed with the
power switch
turned off and then
the power switch
was put in ACCES-
SORY mode twice
without the hybrid
system being
started.
Press the
power
switch while
depressing
the brake
pedal.
During an hybrid
system starting pro-
cedure in the event
that the electronic
key was not func-
tioning properly
( → P. 7 9 4 ) , t h e
power switch was
touched with the
electronic key.
Press the
power
switch
within 10
seconds of
the buzzer
sounding.
Once
The steering lock
could not be
released within 3
seconds of the
power switch being
pressed.
Press the
power
switch while
depressing
the brake
pedal and
moving the
steering
wheel left
and right.
Once
The power switch
has been turned off
with the shift lever
in a position other
than P or N.
Shift the
shift lever to
P.
(Flashes)
(Flashes)
(Flashes)
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7897-2. Steps to take in an emergency
GS450h_OM_OM30D52U_(U)
7
When trouble arises
One of the following may be the cause of the problem:
●One or both of the 12-volt battery terminals may be disconnected.
●The 12-volt battery may be discharged. (→P. 7 9 6 )
Contact your Lexus dealer if the problem cannot be repaired, or if repair proce-
dures are unknown.
When the hybrid system does not start, the following steps can be used as
an interim measure to start the hybrid system if the power switch is func-
tioning normally:
Set the parking brake.
Shift the shift lever to P.
Turn the power switch to ACCESSORY mode.
Press and hold the power switch for about 15 seconds while depressing
the brake pedal firmly.
Even if the hybrid system can be started using the above steps, the system
may be malfunctioning. Have the vehicle inspected by your Lexus dealer.
The interior lights and headlights do not turn on, or the horn does
not sound.
Emergency start function
1
2
3
4
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7957-2. Steps to take in an emergency
GS450h_OM_OM30D52U_(U)
7
When trouble arises
■Stopping the hybrid system
Shift the shift lever to P and press the power switch as you normally do when stop-
ping the hybrid system.
■Replacing the key battery
As the above procedure is a temporary measure, it is recommended that the elec-
tronic key battery be replaced immediately when the battery is depleted. (→P. 6 9 4 )
■Changing power switch modes
Release the brake pedal and press the power switch in step above.
The hybrid system does not start and modes will be changed each time the switch is
pressed.( →P. 1 9 4 )
■When the electronic key does not work properly
●Make sure that the smart access system with push-button start has not been deac-
tivated in the customization setting. If it is off, turn the function on.
(Customizable features: →P. 8 3 3 )
●Check if battery-saving mode is set. If it is set, cancel the function. ( →P. 129)
3
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7977-2. Steps to take in an emergency
GS450h_OM_OM30D52U_(U)
7
When trouble arises
Start the engine of the second vehicle. Increase the engine speed
slightly and maintain at that level for approximately 5 minutes to
recharge the 12-volt battery of your vehicle.
Open and close any of the doors of your vehicle with the power switch
off.
Maintain the engine speed of the second vehicle and start the hybrid
system of your vehicle by turning the power switch to ON mode.
Make sure the “READY” indicator comes on. If the indicator does not
come on, contact your Lexus dealer.
Once the hybrid system has started, remove the jumper cables in the
exact reverse order from which they were connected.
Once the hybrid system starts, have the vehicle inspected at your Lexus
dealer as soon as possible.
■Starting the hybrid system when the 12-volt battery is discharged
The hybrid system cannot be started by push-starting.
■To prevent 12-volt battery discharge
●Turn off the headlights and the audio system while the hybrid system is off.
●Turn off any unnecessary electrical components when the vehicle is running at a
low speed for an extended period, such as in heavy traffic.
■Charging the 12-volt battery
The electricity stored in the 12-volt battery will discharge gradually even when the
vehicle is not in use, due to natural discharge and the draining effects of certain elec-
trical appliances. If the vehicle is left for a long time, the 12-volt battery may dis-
charge, and the hybrid system may be unable to start. (The 12-volt battery recharges
automatically while the hybrid system is operating.)
3
4
5
6
7
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