2007 Lexus GS450h light

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4-3. Do-it-yourself maintenance
4
Maintenance and care
12 volt battery
■Location
The 12 volt battery is located in the
lef
t-hand side of luggage compart-
ment.
■ Ex
terior
Make sure that the battery terminals ar
e not corroded and that there
are no loose connections, cracks, or loose clamps.
Terminals
Hold-down clamp
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 or
when the fluid level in the accumulator is high. 
If the reservoir needs frequent refilli ng, it may indicate a serious problem.

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4-3. Do-it-yourself maintenance
4
Maintenance and care
CAUTION
■Chemicals in the 12 volt battery
A battery contains poisonous and corrosive sulfuric acid and may produce hydro-
gen gas which is flammable and explosive. To reduce the risk of death or serious
injury, take the following precautions while working on or near battery:
●Do not cause sparks by touching the battery terminals with tools.
●Do not smoke or light a match near the battery.
●Avoid contact with eyes, skin and clothes.
●Never inhale or swallow electrolyte.
●Wear protective safety glasses when working near the battery.
●Keep children away from the battery.
■Where to safety charge the 12 volt battery
Always charge the battery in an open area. Do not charge the battery in a garage or
closed room where there is not sufficient ventilation.
■How to recharge the 12 volt battery
Only perform a slow charge (5A or less). The battery may explode if charged at a
quicker rate.
■Emergency measures regarding electrolyte
●If electrolyte gets in your eyes
Flush your eyes with clean water for at least 15 minutes and get immediate medi-
cal attention. If possible, continue to apply water with a sponge or cloth while
traveling to the nearest medical facility.
●If electrolyte gets on your skin 
Wash the affected area thoroughly. If you feel pain or a burning sensation, seek
medical attention immediately.
●If electrolyte gets on your clothes 
It can soak through clothing on to your skin. Immediately take off the clothing and
follow the procedure above if necessary.
●If you accidentally swallow electrolyte 
Drink a large quantity of water or milk. Fo llow with milk of magnesia, beaten raw
egg or vegetable oil. Get emergency medical attention immediately.

378
4-3. Do-it-yourself maintenance
Push and hold the tire pressure
warning reset switch until the tire
pressure warning light blinks
slowly three times and the mes-
sage “PRESSURE INITIAL”
appears on the multi-information
display

.
Wait for a few minutes with the “IG-ON” mode, and then turn
power switch to “OFF” mode.
Registering and selecting ID codes
■ Registering ID codes
2 sets of tire pressure warning va lv
e and transmitter ID codes can be
registered. Once a second set of tire s (winter tires etc.) is registered at
“2nd”, you can switch b etween tire set settings si mply by pressing the
tire pressure warning select switch.
There are 2 settings:
“MAIN” position: The ID code of the tir
e pressure warning valve and
transmitter on the tires originally inst alled on the vehicle is registered.
“2nd” position: The code is not registered. When you replace a new set
of tir
es, purchase tire pressure warning valves and transmitters from
your Lexus dealer and have the new ID code registered by your Lexus
dealer.
STEP4
STEP5

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4-3. Do-it-yourself maintenance
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Maintenance and care
■If you push the tire pressure reset switch accidentally
If initialization is performed, adjust the tire inflation pressure to the specified level
and initialize the system again.
■When the 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 warnin g reset switch, the warning light does
not flash and the setting message does not appear on the multi-information dis-
play.
●After driving for a certain period of time since the initialization has been com-
pleted, the warning light flashes.
■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.

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4-3. 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 fatal or injury accidents.
●Do not mix tires of different makes, models, tread patterns or tread wear.
●Do not use tire sizes other than those recommended by Lexus.
●Do not mix radial, bias-belted, or bias-ply tires.
●Do not mix summer, all season and winter tires.
■When initializing the tire pressure warning system
Do not push the reset switch without first ad justing 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.
NOTICE
■Repairing or replacing tires, wheels and tire pressure warning valves and trans-
mitters
●When removing or fitting the wheels, tires or the tire pressure warning valve and
transmitter, contact your Lexus dealer as the tire pressure warning valve and
transmitter may be damaged if not handled correctly.
●When replacing tires, make sure also to replace the tire pressure warning valve
and transmitter grommets.
■Do not use puncture sealant sprays to repair flats
Puncture sealant sprays may damage tire pressure tire pressure warning valves and
transmitters.

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4-3. Do-it-yourself maintenance
Fuse layout and amperage ratings
■Engine compartment
FuseAmpereCircuit
1FR CTRL-B25H-LP HI, HORN
2RELIEF VLV10Fuel system
3ETCS10
Multiport fuel injection system/
sequential multiport fuel injection
system
4H-LP CLN30Headlight cleaner
5STB-AM30Active stabilizer suspension system
6DEICER25
7FR CTRL-AM30FR TAIL, FR FOG, WASH

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4-3. Do-it-yourself maintenance
4
Maintenance and care
FuseAmpereCircuit
8IG210
Multiport fuel injection system/
sequential multiport fuel injection
system, noise filter
9EFI No.210Fuel system, exhaust system
10H-LP R LWR15Headlight low beam (right)
11H-LP L LWR15Headlight low beam (left)
12D/C CUT30DOME, MPX-B
13IGCT No.37. 5Hybrid battery (traction battery)
14IGCT No.27. 5Hybrid system
15MPX-B7. 5
Power windows, door control system,
power seat, electronically controlled
brake system, combination switch,
electric tilt and telescopic steering,
gauges and meters
16DOME7. 5Interior lights, foot lights, vanity light,
gauges and meters
17ABS MAIN110Electronically controlled brake sys-
tem
18ABS MOTOR30ABS
19ABS MAIN210Electronically controlled brake sys-
tem
20F/ P M P25Fuel system
21EFI25
EFI2, multiport fuel injection system/
sequential multiport fuel injection
system
22INJ20
Multiport fuel injection system/
sequential multiport fuel injection
system

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4-3. Do-it-yourself maintenance
FuseAmpereCircuit
23A/F15Fuel system
24INV W/P10Hybrid system
25IGCT No.120Hybrid system, IGCT No.2, 
IGCT No.3
26FR FOG15Fog light
27FR TAIL10Tail light, rear side marker light
28WA S H20Windshield washer
29HORN10Horn
30H-LP HI20Headlight high beam
31DC/DC140Charging system
32RAD FAN60Electric cooling fans
33LH J/B AM80
S/ROOF, FR P/SEAT LH, TV, A/C,
FUEL OPN, FR WIP, H-LP LVL, 
FR S/HTR LH, A/C W/P
34E/G AM60H-LP CLN, FR CTRL-AM, DEICER,
STB AM
35HEATER50Air conditioning system
36DEFOG50Rear window defogger
37ABS230VSC, ABS
38RH J/B-AM80
AM1, OBD, STOP SW, TI & TE, 
FR P/SEAT RH, STR LOCK, 
SECURITY, ECU-IG R, RH-IG, 
F S/HTR RH, CIG, PWR OUTLET, 
AIR SUS