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5-2. Steps to take in an emergency
RX400h_U
CAUTION
■Maintenance of the tires
Each tire, including the spare (if provided), should be checked monthly when cold
and inflated to the inflation pressure recommended by the vehicle manufacturer on
the vehicle placard or tire inflation pressure label (tire and load information label).
(If your vehicle has tires of a different size than the size indicated on the vehicle
placard or tire inflation pressure label [tire and load information label], you should
determine the proper tire inflation pressure for those tires.)
As an added safety feature, your vehicle has been equipped with a tire pressure
monitoring system (TPMS-tire pressure warning system) that illuminates a low tire
pressure telltale (tire pressure warning light) when one or more of your tires is sig-
nificantly under-inflated. Accordingly, when the low tire pressure telltale (tire pres-
sure warning light) illuminates, you should stop and check your tires as soon as
possible, and inflate them to the proper pressure. Driving on a significantly under-
inflated tire causes the tire to overheat and can lead to tire failure. Under-inflation
also reduces fuel efficiency and tire tread life, and may affect the vehicle's handling
and stopping ability.
Please note that the TPMS (tire pressure warning system) is not a substitute for
proper tire maintenance, and it is the driver's responsibility to maintain correct tire
pressure, even if under-inflation has not reached the level to trigger illumination of
the TPMS low tire pressure telltale (tire pressure warning light).
Your vehicle has also been equipped with a TPMS (tire pressure warning system)
malfunction indicator to indicate when the system is not operating properly. The
TPMS (tire pressure warning system) malfunction indicator is combined with the
low tire pressure telltale (tire pressure warning light). When the system detects a
malfunction, the telltale will flash for approximately one minute and then remain
continuously illuminated. This sequence will continue upon subsequent vehicle
start-ups as long as the malfunction exists. When the malfunction indicator is illumi-
nated, the system may not be able to detect or signal low tire pressure as intended.
TPMS (tire pressure warning system) malfunctions may occur for a variety of rea-
sons, including the installation of replacement or alternate tires or wheels on the
vehicle that prevent the TPMS (tire pressure warning system) from functioning
properly. Always check the TPMS (tire pressure warning system) malfunction tell-
tale after replacing one or more tires or wheels on your vehicle to ensure that the
replacement or alternate tires and wheels allow the TPMS (tire pressure warning
system) to continue to function properly.
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5-2. Steps to take in an emergency
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If a warning message is displayed
Stop the vehicle immediately.
A buzzer sounds and a warning message is shown on the multi-informa-
tion display. The following warnings indicate the possibility of damage to
the vehicle that may lead to an accident. Immediately stop the vehicle in a
safe place and contact your Lexus dealer.
Wa r n i n g m e s s a g eDetails
(Flashing)
Indicates an abnormal engine oil pressure. The warning light may turn on if the engine oil pres-
sure is too low.
Malfunction in the hybrid system.
If a warning is shown on the multi-information display, stay calm and per-
form the following actions:
Master warning light
The master warning light also
comes on or flashes in order to
indicate that a message is cur-
rently being displayed on the
multi-information display.
Multi-information display
If any of the warning light turns on again after performing the following
actions, contact your Lexus dealer.
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5-2. Steps to take in an emergency
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Have the vehicle inspected by your Lexus dealer immediately.
A buzzer sounds and a warning message is shown on the multi-informa-
tion display. Failing to investigate the cause of the following warnings may
lead to the system operating abnormally and possibly cause an accident.
Have the vehicle inspected by your Lexus dealer immediately.
Indicates a malfunction in the AWD system.
(Flashing)
Indicates a hybrid system is over heating.
Wa r n i n g m e s s a g eDetails
Malfunction in the automatic headlight leveling sys-
tem.
Wa r n i n g m e s s a g eDetails
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5-2. Steps to take in an emergency
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Have the malfunction repaired immediately.After taking the specified steps to co rrect the suspected problem, check
that the warning light turns off.
■Changing the engine oil (U.S.A. only)
Make sure to reset the oil change system. ( →P. 3 2 1 )
■Warning light display in radar cruise mode
In the following cases, the warning light may not be displayed even if vehicle-to-
vehicle distance closes.
●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
Wa r n i n g m e s s a g eDetailsCorrection
procedure
(Comes on for 8 seconds.)
Indicates that the fuel
door left open after refuel-
ing when start the vehicle/
leave the fuel door open
for more than 30 minutes
during refueling.
Close the fuel lid.
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5-2. Steps to take in an emergency
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Replacing a flat tireChock the tires.
Slightly loosen the wheel nuts (one
turn).
Turn the tire jack portion “A” by
hand until the notch of the jack is in
contact with the jack point.
STEP1
Flat tireWheel chock positions
Front
Left-hand
sideBehind the
rear right-
hand side tire
Right-
hand sideBehind the
rear left-
hand side tire
Rear
Left-hand
sideIn front of the
front right-
hand side tire
Right-
hand sideIn front of the
front left-
hand side tire
STEP2
STEP3
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5-2. Steps to take in an emergency
RX400h_URaise the vehicle until the tire is
slightly raised off the ground.
Remove all the wheel nuts and the
tire.
When resting the tire on the
ground, place the tire so that the
wheel design faces up to avoid
scratching the wheel surface.
STEP4
STEP5
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5-2. Steps to take in an emergency
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If the hybrid system will not start
If the hybrid system will not start, even though correct starting procedures
are being followed (
→P. 131), consider each of the following points.
■The hybrid system will not start even when the starter motor oper-
ates normally.
One of the following may be the cause of the problem.
● There may not be sufficient fuel in the vehicle’s tank.
Refuel your vehicle.
● The hybrid system may be flooded.
Try to restart the hybrid system once more following correct
starting procedures. ( →P. 131)
● There may be a malfunction in the hybrid vehicle immobilizer sys-
tem. (→ P. 8 3 )
■ The interior lights and headlights are dim, or the horn does not
sound or sounds at a low volume.
One of the following may be the cause of the problem.
● The 12-volt battery may be discharged. ( →P. 4 2 1 )
● The 12-volt battery terminal connections may be loose or cor-
roded.
■ The interior lights and headlights do not turn on, or the horn does
not sound.
One of the following may be the cause of the problem.
● One or both of the 12-volt battery terminals may be discon-
nected.
● The 12-volt battery may be discharged. ( →P. 4 2 1 )
Contact your Lexus dealer if the problem cannot be repaired, or if
repair procedures are unknown.
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If the 12-volt battery is discharged
The following procedures may be used to start the hybrid system if the vehi-
cle’s battery is discharged.
You can call your Lexus dealer, or qualified repair shop.
If you have a set of jumper (or booster) cables and a second vehicle
with a 12-volt battery, you can jump start your Lexus following the steps
below.Remove the engine compartment cover.
(→ P. 3 1 7 )
Connecting the jumper cables.
If required, remove all vent plugs from the booster battery. Lay a
cloth over the open vents on the booster battery. (This helps reduce
the explosion hazard, personal injuries and burns.)
Positive (+) battery terminal on your vehicle
Positive (+) battery terminal on the second vehicle
Negative (-) battery terminal on the second vehicle
Connect the jumper cable to ground on your vehicle as shown in the
illustration. Start the hybrid system of the second vehicle. Increase the gas-
oline engine speed slightly and maintain at that level for
approximately 5 minutes to recharge the battery of your vehi-
cle.
Maintain the gasoline engine speed on the second vehicle and
start the vehicle’s hybrid system.
STEP1
STEP2
STEP3
STEP4