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6-2. Maintenance
Head restraints• Do the head restraints movesmoothly and lock securely?
Indicators/buzzers• Do the indicators and buzzers func-tion properly?
Lights
• Do all the lights come on?
• Are the headlights aimed correctly? (→ P. 477)
Parking brake
• Moves smoothly?
• When parked on a slope and the
parking brake is on, is the vehicle
securely stopped?
Seat belts
• Do the seat belts operate smoothly?
• The seat belts should not be dam-aged.
Seats• Do the seat controls operate prop-erly?
Steering wheel
• Does the steering wheel rotatesmoothly?
• Does the steering wheel have the correct amount of free play?
• There should not be any strange sounds coming from the steering
wheel.
ItemsCheck points
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GS450h_OM_OM30F70U_(U)
4216-2. Maintenance
6
Maintenance and care
Ve h i c l e e x t e r i o r
ItemsCheck points
Doors/trunk• Do the doors/trunk operatesmoothly?
Engine hood• Does the engine hood lock systemwork properly?
Fluid leaks
• There should not be any signs of fluidleakage after the vehicle has been
parked.
Ti r e s
• Is the tire inflation pressure correct?
• The tires should not be damaged orexcessively worn.
• Have the tires been rotated accord- ing to the maintenance schedule?
• The wheel nuts should not be loose.
Windshield wipers
• The wiper blades should not show any signs of cracking, splitting, wear,
contamination or deformation.
• The wiper blades should clear the windshield without streaking or skip-
ping.
CAUTION
■If the hybrid system is operating
Turn the hybrid system off and ensure that there is adequate ventilation before per-
forming maintenance checks.
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6-3. Do-it-yourself maintenance
Hood
Pull the hood lock release lever.
The hood will pop up slightly.
Pull up the auxiliary catch lever
and lift the hood.
Release the lock from the inside of the vehicle to open the hood.
1
2
CAUTION
■Pre-driving check
Check that the hood is fully closed and locked.
If the hood is not locked properly, it may open while the vehicle is in motion and
cause an accident, which may result in death or serious injury.
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6-3. Do-it-yourself maintenance
■Adding engine oil
If the oil level is below or near the
low level mark, add engine oil of
the same type as that already in
the engine.
Make sure to check the oil type and prepare the items needed before
adding oil.Remove the oil filler cap by turning it counterclockwise.
Add engine oil slowly, checking the dipstick.
Install the oil filler cap by turning it clockwise.
■Engine oil consumption
A certain amount of engine oil will be consumed while driving. In the following situa-
tions, oil consumption may increase, and engine oil may need to be refilled in
between oil maintenance intervals.
●When the engine is new, for example directly after purchasing the vehicle or after
replacing the engine
●If low quality oil or oil of an inappropriate viscosity is used
●When driving at high engine speeds or with a heavy load, or when driving while
accelerating or decelerating frequently
●When leaving the engine idling for a long time, or when driving frequently through
heavy traffic
Engine oil selection →P. 5 7 7
Oil quantity (Low → Full) 1.6 qt. (1.5 L, 1.3 Imp.qt.)
Items Clean funnel
1
2
3
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6-3. Do-it-yourself maintenance
■Before recharging
When recharging, the 12-volt battery produces hydrogen gas which is flammable
and explosive. Therefore, observe the following precautions before recharging:
●If recharging with the 12-volt battery installed on the vehicle, be sure to disconnect
the ground cable.
●Make sure the power switch on the charger is off when connecting and discon-
necting the charger cables to the 12-volt battery.
■After recharging/reconnecting the 12-volt battery
●The hybrid system may not start. Follow the procedure below to initialize the sys-
tem.Shift the shift lever to P.
Open and close any of the doors.
Restart the hybrid system.
●Unlocking the doors using the smart access system with push-button start may not
be possible immediately after reconnecting the 12-volt battery. If this happens, use
the wireless remote control or the mechanical key to lock/unlock the doors.
●Start the hybrid system with the power switch in ACCESSORY mode. The hybrid
system may not start with the power switch turned off. However, the hybrid system
will operate normally from the second attempt.
●The power switch mode is recorded by the vehicle. If the 12-volt battery is recon-
nected, the vehicle will return the power switch mode to the status it was in before
the 12-volt battery was disconnected. Make sure to turn off the power switch
before disconnect the 12-volt battery. Take extra care when connecting the 12-volt
battery if the power switch mode prior to discharge is unknown.
If the system will not start even after multiple attempts at all methods above, contact
your Lexus dealer.
1
2
3
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GS450h_OM_OM30F70U_(U)
4496-3. Do-it-yourself maintenance
6
Maintenance and care
■If the tread on snow tires wears down below 0.16 in. (4 mm)
The effectiveness of the tires as snow tires is lost.
■Situations in which the tire pressure warning system may not operate properly
●In the following cases, the tire pressure warning system may not operate properly.
• If non-genuine Lexus wheels are used.
• A tire has been replaced with a tire that is not an OE (Original Equipment) tire.
• A tire has been replaced with a tire that is not of the specified size.
• Tire chains etc. are equipped.
• Lock nuts are equipped.
• An auxiliary-supported run-flat tire is equipped.
• If a window tint that affects the radio wave signals is installed.
• If there is a lot of snow or ice on the vehicle, particularly around the wheels or wheel housings.
• If the tire inflation pressure is extremely higher than the specified level.
●Performance may be affected in the following situations.
• Near a TV tower, electric power plant, gas station, radio station, large display, airport or other facility that generates strong radio waves or electrical noise
• When carrying a portable radio, cellular phone, cordless phone or other wire- less communication device
Vehicles with the tire inflation pressure display function: If tire position information
is not correctly displayed due to the radio wave conditions, the display may be
corrected by driving and changing the radio wave conditions.
●When the vehicle is parked, the time taken for the warning to start or go off could
be extended.
●When tire inflation pressure declines rapidly for example when a tire has burst, the
warning may not function.
■The initialization operation
●Make sure to carry out initialization after adjusting the tire inflation pressure.
Also, make sure the tires are cold before carrying out initialization or tire inflation
pressure adjustment.
●If you have accidentally turned the power switch off during initialization, it is not
necessary to press the reset switch again as initialization will restart automatically
when the power switch has been turned to ON mode for the next time.
●If you accidentally press the reset switch when initialization is not necessary, adjust
the tire inflation pressure to the specified level when the tires are cold, and conduct
initialization again.
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6-3. Do-it-yourself maintenance
Checking and replacing fuses
Turn the power switch off.
After a system failure, see “Fuse layout and amperage ratings” for
details about which fuse to check. (→P. 466)
Open the fuse box cover.
XEngine compartment
Remove the engine compart-
ment cover ( →P. 4 3 0 ) a n d
remove all of the clips.
Push the tabs on either side to
detach the lock and lift the lid off
while pulling the lock plate.
When installing the lid, check that
the lock plate and the tabs on either
side are connected correctly.
If any of the electrical components do not operate, a fuse may have
blown. If this happens, check and replace the fuses as necessary.
1
2
3
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4676-3. Do-it-yourself maintenance
6
Maintenance and care
11ABS MAIN 210Brake system
12ABS MAIN 110Brake system
13IGCT NO.130IGCT NO.2, IGCT NO.3, IGCT NO.4,
IGCT NO.5
14ECU-B7. 5VGRS, smart access system with push-but-
ton start
15INV W/P10Hybrid system
16ETCS10Multiport fuel injection system/sequential
multiport fuel injection system
17EPS-B10Electric power steering system
18D/C CUT30DOME, MPX-B
19HORN10Horn
20ODS5Occupant classification system
21TV7. 5Remote Touch screen
22P/ I - B N O. 280IG2 MAIN, EFI MAIN, EDU, F/PMP, A/F
23ABS NO.230Motor relay
24P/ I - B N O.150H-LP HI RH, H-LP HI LH, DRL
25H-LP LO30H-LP LO RH, H-LP LO LH
26LH J/B-B40Left-hand junction block
27RH J/B-B40Right-hand junction block
28VGRS40VGRS
29OIL PMP60Oil pump
30IGCT NO.57. 5Power management system, shift position
sensor
31WIP-S7. 5Windshield wipers, driver support system
32WA S H - S5Windshield washer, driver support system
33COMB SW5Windshield wipers
FuseAmpereCircuit
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