flat tire LEXUS RX400H 2008 Owner's Manual

341
4-3. Do-it-yourself maintenance
4
Maintenance and care
RX400h_U
■Tire inflation pressure check interval
You should check tire inflation pressure every two weeks, or at least once a month.
Do not forget to check the spare.
■Inspection and adjustment procedure
Ti r e v a l v e
Tire pressure gauge
Remove the tire valve cap.
Press the tip of the tire pressure gauge onto the tire valve.
Read the pressure using the graduations of the gauge.
If the tire inflation pressure is not within the recommended lev-
els, adjust inflate the tire.
If you add too much air, press the center of the valve to lower.
After completing the tire inflation pressure measurement and
adjustment, apply soapy water to the valve and check for leak-
age.
Reinstall the tire valve cap.
STEP1
STEP2
STEP3
STEP4
STEP5
STEP6

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4-3. Do-it-yourself maintenance
RX400h_U
■Effects of incorrect tire inflation pressure
Driving with incorrect tire inflation pressure may result in the following:
●Reduced fuel efficiency
●Reduced driving comfort and tire life
●Reduced safety
●Damage to the drive train
If a tire needs frequent refilling, have it checked by your Lexus dealer.
■Instructions for checking tire inflation pressure
When checking tire inflation pressure, observe the following:
●Check only when the tires are cold.
If your vehicle has been parked for at least 3 hours and has not been driven for
more than 1 mile or 1.5 km, you will get an accurate cold tire inflation pressure
reading.
●Always use a tire pressure gauge.
The appearance of the tire can be misleading. In addition, tire inflation pressures
that are even just a few pounds off can degrade ride and handling.
●Do not bleed or reduce tire inflation pressure after driving. It is normal for the tire
inflation pressure to be higher after driving.
●Never exceed the vehicle capacity weight.
Passengers and luggage weight should be placed so that the vehicle is balanced.

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4-3. Do-it-yourself maintenance
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Maintenance and care
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CAUTION
■Proper inflation is critical to save tire performance
Keep your tires properly inflated.
Otherwise, the following conditions may occur and result in an accident causing
death or serious injury.
●Excessive wear
●Uneven wear
●Poor handling
●Possibility of blowouts resulting from overheated tires
●Poor sealing of the tire bead
●Wheel deformation and/or tire separation
●A greater possibility of tire damage from road hazards
NOTICE
■When inspecting and adjusting tire inflation pressure
Be sure to reinstall the tire valve caps.
Without the valve caps, dirt or moisture could get into the valve and cause air leak-
age, which could result in an accident. If the caps have been lost, replace them as
soon as possible.

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4-3. Do-it-yourself maintenance
RX400h_U
Wheels
■When replacing wheels
The wheels of your Lexus are equipped with tire pressure warning valves and trans-
mitters that allow the tire pressure warning system to provide advanced warning in
the event of a loss in tire inflation pressure. Whenever wheels are replaced, the tire
pressure warning valves and transmitters must be installed. (→P. 3 3 2 )
If a wheel is bent, cracked or heavily corroded, it should be replaced. Oth-
erwise, the tire may separate from the wheel or cause loss of handling con-
trol.
■Wheel selection
When replacing wheels, care should be taken to ensure that they
are equivalent to those removed in load capacity, diameter, rim
width, and offset.
Replacement wheels are available at your Lexus dealer.
Lexus does not recommend using:
• Wheels of different sizes or types
• Used wheels
• Bent wheels that have been straightened
■ Aluminum wheel precautions
● Use only Lexus wheel nuts and wrenches designed for use with
your aluminum wheels.
● When rotating, repairing or changing your tires, check that the
wheel nuts are still tight after driving 1000 miles (1600 km).
● Be careful not to damage the aluminum wheels when using tire
chains.
● Use only Lexus genuine balance weights or equivalent and a
plastic or rubber hammer when balancing your wheels.

When trouble arises5
377
RX400h_U
5-1. Essential information .... 378If your vehicle needs to be towed ...................................... 378
If you think something is wrong ...................................... 385
Event data recorder.............. 386
5-2. Steps to take in an emergency ................... 388
If a warning light turns on or a warning buzzer
sounds... ................................. 388
If a warning message is displayed................................ 398
If you have a flat tire............... 408
If the hybrid system will not start ................................... 418
If the shift lever cannot be shifted from P ........................ 419
If you lose your keys .............. 420
If the 12-volt battery is discharged ............................. 421
If your vehicle overheats ..... 424
If the vehicle becomes stuck......................................... 427

5
When trouble arises
385
5-1. Essential information
RX400h_U
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably needs
adjustment or repair. Contact your Lexus dealer as soon as possible.
■Visible symptoms
●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 normal
■ Audible symptoms
●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
■ Operational symptoms
●Engine missing, stumbling or running rough
● 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, sp ongy feeling, pedal almost touches
the floor

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5-2. Steps to take in an emergency
RX400h_U
*1:Driver’s seat belt reminder:The driver’s seat belt reminder sounds to alert the driver that his or her seat belt
is not fastened. Once the engine switch is turned to the ON or START position,
the buzzer sounds for 4 to 8 seconds. If the vehicle has reached a speed of at
least 12 mph (20 km/h), the buzzer sounds intermittently for 10 seconds. Then,
if the seat belt is still unfastened, the buzzer will sound in a different tone for 20
more seconds.
*
2: Front passenger’s seat belt reminder:
The front passenger’s seat belt reminder sounds to alert the front passenger that
his or her seat belt is not fastened. The buzzer sounds intermittently for 10 sec-
onds after the vehicle has reached a speed of at least 12 mph (20 km/h). Then, if
the seat belt is still unfastened, the buzzer will sound in a different tone for 20
more seconds.
Warning lightWarning light/DetailsCorrection procedure
Tire pressure warning light
When the light comes on:
Low tire inflation pressure.Adjust the tire inflation pres-
sure.
When the light comes on after
blinking for 1 minute:
Malfunction in the tire pres-
sure warning system
Have the system inspected by
your Lexus dealer.
Master warning light A buzzer sounds and the
warning light comes on and
flashes to indicate that the
master warning system has
detected a malfunction.
Take appropriate action in
accordance with the message
displayed on the multi-infor-
mation display.

5
When trouble arises
393
5-2. Steps to take in an emergency
RX400h_U
■Key reminder buzzer
The buzzer indicates that the key has not been removed from the engine switch
(with the engine switch in the ACC or LOCK position and the driver’s door
opened).
■If the malfunction indicator lamp comes on while driving
First check the following:
●Is your vehicle low on gas?
If it is, refuel the vehicle immediately.
●Is the fuel tank cap loose?
If it is, tighten it securely.
The lamp will go off after taking several driving trips.
If the light does not go off even after several trips, contact your Lexus dealer as soon
as possible.
■Front passenger detection sensor and passenger seat belt reminder
●If luggage is placed on the front passenger seat, the front passenger detection
sensor may cause the warning light to flash, even if a passenger is not sitting in the
seat.
●If a cushion is placed on the seat, the sensor may not detect a passenger, and the
warning light may not operate properly.
■Changing the engine oil (U.S.A. only)
Make sure to reset the oil change system. ( →P. 3 2 1 )
■When the tire pressure warning light comes on
Check the tire inflation pressure and adjust to the appropriate level. Pushing the tire
pressure warning reset switch does not turn off the tire pressure warning light.
■The tire pressure warning light may turn on due to natural causes
The tire pressure warning light may turn on due to natural causes such as natural air
leaks or tire inflation pressure changes caused by temperature. In this case, adjust-
ing the tire inflation pressure will turn off the warning light (after a few minutes).

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5-2. Steps to take in an emergency
RX400h_U
■When a tires is replaced with a spare tire
The spare tire is also equipped with the tire pressure warning valve and transmitter.
The tire pressure warning light will turn on if the tire inflation pressure of the spare
tire is low. If a tire goes flat, even though the flat tire is replaced with the spare tire,
the tire pressure warning light does not turn off. Replace the spare tire with the
repaired tire and adjust the proper tire inflation pressure. The tire pressure warning
light will turn off after a few minutes.
■If the tire pressure warning system is inoperative
The tire pressure warning system will be disabled in the following conditions:
(When the condition becomes normal, the system will work properly.)
●If tires not equipped with tire pressure warning valves and transmitters are used.
●If the ID code on the tire pressure warning valves and transmitters is not regis-
tered in the tire pressure warning computer.
●If the tire pressure warning select switch is set to a different tire setting.
●If the tire inflation pressure is 73 psi (500 kPa, 5.1 kgf/cm2 or bar) or higher.
The tire pressure warning system may be disabled in the following conditions:
(When the condition becomes normal, the system will work properly.)
●If electronic devices or facilities using similar radio wave frequencies are nearby.
●If a radio set at similar frequencies is in use in the vehicle.
●If a window tint that affects the radio wave signals is installed.
●If there is a lot of snow or ice on the vehicle, in particular around the wheels or
wheel housings.
●If non-genuine Lexus wheels are used. (Even if you use Lexus wheels, the tire
pressure warning system may not work properly with some types of tires.)
●If tire chains are used.
●If the spare tire is in a location subject to poor radio wave signal reception.
●If a large metallic object which can interfere with signal reception is put in the
trunk.
■If the tire pressure warning light comes on after blinking for 1 minute frequently
If the tire pressure warning light comes on after blinking for 1 minute frequently
when the engine switch is turned to ON position, have it checked by your Lexus
dealer.

5
When trouble arises
395
5-2. Steps to take in an emergency
RX400h_U
CAUTION
■If the tire pressure warning light comes on
Be sure to observe the following precautions. Failure to do so could cause 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 pres-
sure 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 the tire is flat,
change to the spare tire and have the flat tire repaired by the nearest Lexus
dealer.
●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.