2008 LEXUS RX400H Check

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4-3. Do-it-yourself maintenance
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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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■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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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.

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4-3. Do-it-yourself maintenance
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Maintenance and care
RX400h_U
■Changing interval
Inspect and replace the air conditioning filter according to the maintenance sched-
ule. In dusty areas or areas with heavy traffic flow, early replacement may be
required. (For scheduled maintenance information, please refer to the “Warranty
and Service Guide”, “Owner's Manual Supplement” or “Scheduled Maintenance”.)
■If air flow from the vents decreases dramatically
The filter may be clogged. Check the filter and replace if necessary.
NOTICE
■When using the air conditioning system
Make sure that a filter is always installed.
Using the air conditioning system without a filter may cause damage to the system.

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4-3. Do-it-yourself maintenance
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Checking and replacing fuses
If any of the electrical components do not operate, a fuse may have blown.
If this happens, check and replace the fuses as necessary.
Turn the engine switch to the LOCK position.
Remove the engine compartment cover. ( →P. 317)
Open the fuse box cover.
Engine compartment
Push the tabs in and lift the lid
off.STEP1
STEP2
STEP3

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4-3. Do-it-yourself maintenance
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Maintenance and care
RX400h_U
Driver's side instrument panelRemove the lid.
After a system failure, see “Fuse layout and amperage ratings”
(→ P. 355) for details about which fuse to check.
Remove the fuse with the pull-
out tool.
STEP4
STEP5

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4-3. Do-it-yourself maintenance
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Check if the fuse has blown.Type A
Normal fuse
Blown fuse
Replace it with one of an appro-
priate amperage rating. The
amperage rating can be found
on the fuse box lid.
Type B and C
Type B
Type C
Normal fuse
Blown fuse
Replace it with one of an appro-
priate amperage rating. The
amperage rating can be found
on the fuse box lid.
STEP6

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Headlight aim (vehicles with discharge headlights)
■Vertical movement adjusting screw and bolt
Adjustment screw
Adjustment bolt
■ Before checking the headlight aim
Make sure the vehicle has a full tank of gas and the area around
the headlight is not deformed.
Park the vehicle on level ground.
Sit in the driver’s seat.
Bounce the vehicle several times.
■ Adjusting the headlight aim
Turn the screw in either direc-
tion using a Phillips-head screw-
driver.
Remember the turning direction
and the number of turns in mind.
Turn the bolt the same number
of turns and in the same direc-
tion as step 1 using a Phillips-
head screwdriver.
If the error is over the value
specified above, take the vehicle
to your Lexus dealer to adjust
the headlight aim.
STEP1
STEP2
STEP3
STEP4
STEP1
STEP2