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6456-3. Do-it-yourself maintenance
6
Maintenance and care
■Checking fluid level
The brake fluid level should be
between the “MAX” and “MIN”
lines on the tank.
■Adding fluid
Make sure to check the fluid type and prepare the necessary item.
■Brake fluid can absorb moisture from the air
Excess moisture in the brake fluid can cause a dangerous loss of braking efficiency.
Use only newly opened brake fluid.
Brake fluid
Fluid typeFMVSS No.116 DOT 3 or SAE J1703 brake fluid
ItemsClean funnel
CAUTION
■When filling the reservoir
Take care as brake fluid can harm your hands and eyes and damage painted sur-
faces.
If fluid gets on your hands or in your ey es, flush the affected area with clean water
immediately.
If you still experience discomfort, see a doctor.
NOTICE
■If the fluid level is low or high
It is normal for the brake fluid level to go down slightly as the brake pads wear out
or when the fluid level in the accumulator is high.
If the reservoir needs frequent refil ling, there may be a serious problem.
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Maintenance and care
CAUTION
■Chemicals in the 12-volt battery
The 12-volt battery contains poisonous and corrosive sulfuric acid and may pro-
duce hydrogen gas which is flammable and explosive. To reduce the risk of death
or serious injury, take the following precautions while working on or near the 12-
volt battery:
●Do not cause sparks by touching the 12-volt battery terminals with tools.
●Do not smoke or light a match near the 12-volt battery.
●Avoid contact with eyes, skin and clothes.
●Never inhale or swallow electrolyte.
●Wear protective safety glasses when working near the 12-volt battery.
●Keep children away from the 12-volt battery.
■Where to safely charge the 12-volt battery
Always charge the 12-volt battery in an open area. Do not charge the 12-volt bat-
tery in a garage or closed room wh ere there is insufficient ventilation.
■How to recharge the 12-volt battery
Observe the following precautions when re charging the 12-volt battery. Failure to
do so may damage the 12 -volt battery and cause de ath or serious injury.
●Slow charge: Recharge at a current of 5 A or less and make sure that the
recharging period does not exceed a total of 12 hours.
●Quick charge: Recharge at a current of 15 A or less and make sure that the
recharging period does not exceed 60 minutes.
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6536-3. Do-it-yourself maintenance
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Maintenance and care
Your vehicle is equipped with a tire pressure warning system that uses tire
pressure warning valves and transmitters to detect low tire inflation pres-
sure before serious problems arise.
Vehicles without the tire inflation pressure display function
If the tire pressure drops below a predetermined level, the driver is
warned by a warning light. ( P. 715)
Vehicles with the tire inflation pressure display function
●If the tire pressure drops below a predetermined level, the driver is
warned by a screen display and a warning light. ( P. 740)
●The tire pressure detected by the tire pressure warning system can be
displayed on the multi- information display. (P. 9 7 )
◆Installing tire pressure warning valves and transmitters
When replacing tires or wheels, tire pressure warning valves and trans-
mitters must also be installed.
When new tire pressure warning valves and transmitters are installed,
new ID codes must be registered in the tire pressure warning computer
and the tire pressure warning system must be initialized. Have tire pres-
sure warning valve and transmitter ID codes registered by your Lexus
dealer. ( P. 655)
◆Initializing the tire pressure warning system
■The tire pressure warning system must be initialized in the following
circumstances:
●When rotating the tires.
●When the tire inflation pressure is changed such as when changing
traveling speed or load weight.
When the tire pressure warning system is initialized, the current tire
inflation pressure is set as the benchmark pressure.
Tire pressure warning system
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GS450h_U (OM30D01U)
6-3. Do-it-yourself maintenance
■How to initialize the tire pressure warning systemPark the vehicle in a safe place and turn the power switch off.
Initialization cannot be performed while the vehicle is moving.
Adjust the tire inflation pressure to the specified cold tire inflation
pressure level. ( P. 790)
Make sure to adjust the tire pressure to the specified cold tire inflation pres-
sure level. The tire pressure warning sy stem will operate based on this pressure
level.
Turn the power switch to ON mode.
Press and hold the tire pres-
sure warning reset switch until
the tire pressure warning light
blinks slowly 3 times.
Wait for a few minutes with the power switch in ON mode and then
turn the power switch off.
1
2
3
4
5
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Maintenance and care
◆Registering ID codes
The tire pressure warning valve and transmitter is equipped with a
unique ID code. When replacing a tire pressure warning valve and
transmitter, it is necessary to register the ID code. Have the ID code
registered by your Lexus dealer.
■When to replace your vehicle’s tires
Tires should be replaced if:
●You have tire damage such as cuts, splits , cracks deep enough to expose the fabric,
and bulges indicating internal damage
●A tire goes flat repeatedly or cannot be properly repaired due to the size or loca-
tion of a cut or other damage
If you are not sure, consul t with your Lexus dealer.
■Replacing tires and wheels
If the ID code of the tire pressure warning valve and transmitter is not registered, the
tire pressure warning system will not work properly. After driving for about 20 min-
utes, the tire pressure warning light blinks for 1 minute and stays on to indicate a sys-
tem malfunction.
■Tire life
Any tire over 6 years old must be checked by a qualified technician even if it has sel-
dom or never been used or damage is not obvious.
■Routine tire inflation pressure checks
The tire pressure warning system does not replace routine tire inflation pressure
checks. Make sure to check tire inflation pressure as part of your routine of daily
vehicle checks.
■When rotating the tires (vehicles with the tire inflation pressure display function)
Make sure that the power switch is off. If the tires are rotated while the power switch
is in ON mode, the tire position information will not be updated.
If this accidentally occurs, either turn the power switch to off and then to ON mode,
or initialize the system after checking that the tire pressure is properly adjusted.
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GS450h_U (OM30D01U)
6-3. Do-it-yourself maintenance
■When initialization of the tire pressure warning system has failed
Initialization can be completed in a few minutes. However, in the following cases, the
settings have not been recorded and the system will not operate properly. If
repeated attempts to record tire inflation pressure settings are unsuccessful, have
the vehicle inspected by your Lexus dealer.
●When operating the tire pressure warning reset switch, the tire pressure warning
light does not blink 3 times.
●After carrying out the initialization procedure, the tire pressure warning light blinks
for 1 minute then stays on after driving for 20 minutes.
■Tire pressure warning system certification
MODEL/FCC IDs:
Transmitter: PAXPMVC010
Initiator: HYQ22AAA
For vehicles sold in the U.S.A.
NOTE:
This device complies with Part 15 of the FCC Rules. Operation is subject to the fol-
lowing two conditions: (1) this device may not cause harmful interference, and (2)
this device must accept any interference received, including interference that may
cause undesired operation.
FCC WARNING:
Changes or modifications not expressly ap proved by the party responsible for com-
pliance could void the user’s authority to operate the equipment.
For vehicles sold in Canada
NOTE:
Operation is subject to the following two conditions: (1) this device may not cause
interference, and (2) this device must acc ept any interference, including interfer-
ence that may cause undesired operation of the device.
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6596-3. Do-it-yourself maintenance
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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 (r adial, 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 re set 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 elec tronic devices (vehicles with the tire
inflation pressure display function)
●Users of any electrical medical device other than implanted pacemakers and
implanted cardiac 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 implanted pacemakers or car-
diac defibrillators should not come within
17.7 in. (450 mm) of the tire pressure warn-
ing system initiators. The radio waves may
affect the operation of such devices.
Page 674 of 860
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GS450h_U (OM30D01U)
6-3. Do-it-yourself maintenance
■Engine compartment
Fuse layout and amperage ratings
FuseAmpereCircuit
1IGN10Starting system
2INJ10Multiport fuel injection system/sequential
multiport fuel injection system
3EFI NO.210Air intake system, exhaust system
4IG2 MAIN20IGN, GAUGE, INJ, AIR BAG, IG2 NO.1,
LH-IG2
5EFI MAIN25Multiport fuel injection system/sequential
multiport fuel injection system, EFI NO.2
6A/F15Air flow sensor
7EDU20Multiport fuel injection system/sequential
multiport fuel injection system
8F/ P M P25Multiport fuel injection system/sequential
multiport fuel injection system
9H-LP RH-LO20Right-hand headlight (low beam)*
10H-LP LH-LO20Left-hand headlight (low beam)*