Page 632 of 862

631
GS450h_U (OM30D01U)6-3. Do-it-yourself maintenance
6
Maintenance and care
Do-it-yourself service precautions
If you perform maintenance by yourself, be sure to follow the correct
procedure as given in these sections.
ItemsPa r t s a n d t o o l s
12-volt battery condition ( →P. 6 4 7 )
•Grease
• Conventional wrench
(for terminal clamp bolts)
Brake fluid level ( →P. 6 4 5 )
•FMVSS No.116 DOT 3 or SAE J1703
brake fluid
• Rag or paper towel
• Funnel (used only for adding brake fluid)
Engine/power control unit
coolant level ( →P. 6 4 2 )
•“To y o t a Super Long Life Coolant” or
a similar high quality ethylene glycol-
based non-silicate, non-amine, non-
nitrite and non-borate coolant with
long-life hybrid organic acid technol-
ogy
For the U.S.A.:
“Toyota Super Long Life Coolant” is
pre-mixed with 50% coolant and
50% deionized water.
For Canada:
“Toyota Super Long Life Coolant” is
pre-mixed with 55% coolant and
45% deionized water.
• Funnel (used only for adding coolant)
Engine oil level ( →P. 6 3 9 )
• “Toyota Genuine Motor Oil” or
equivalent
• Rag or paper towel
• Funnel (used only for adding engine oil)
GS450h_U.book Page 631 Monday, January 23, 2012 10:20 AM
Page 638 of 862
637
GS450h_U (OM30D01U)6-3. Do-it-yourself maintenance
6
Maintenance and care
Engine compartment
■12-volt battery
→ P. 6 4 7
Engine oil level dipstick
(→P. 639)
Engine coolant reservoir (→P. 6 4 2 )
Engine oil filler cap (→P. 6 4 0 )
Power control unit coolant res-
ervoir ( →P. 6 4 2 ) Brake fluid reservoir
(→P. 645)
Fuse box ( →P. 6 7 0 )
Washer fluid tank ( →P. 6 4 6 )
Electric cooling fans
Condenser ( →P. 6 4 4 )
Radiator ( →P. 6 4 4 )1
2
3
4
5
6
7
8
9
10
GS450h_U.book Page 637 Monday, January 23, 2012 10:20 AM
Page 648 of 862
647
GS450h_U (OM30D01U)6-3. Do-it-yourself maintenance
6
Maintenance and care
12-volt battery
The 12-volt battery is located on the
left-hand side of luggage compart-
ment.
Pull the strap upwards to lift up the
12-volt battery cover.
Make sure that the 12-volt battery terminals are not corroded and that
there are no loose connections, cracks, or loose clamps. Te r m i n a l s
Hold-down clamp
Location
Removing the 12-volt battery cover
Exterior
1
2
GS450h_U.book Page 647 Monday, January 23, 2012 10:20 AM
Page 649 of 862

648
GS450h_U (OM30D01U)
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
GS450h_U.book Page 648 Monday, January 23, 2012 10:20 AM
Page 650 of 862

GS450h_U (OM30D01U)
6496-3. Do-it-yourself maintenance
6
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 where there is insufficient ventilation.
■How to recharge the 12-volt battery
Observe the following precautions when recharging the 12-volt battery. Failure to
do so may damage the 12-volt battery and cause death 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.
GS450h_U.book Page 649 Monday, January 23, 2012 10:20 AM
Page 651 of 862

650
GS450h_U (OM30D01U)
6-3. Do-it-yourself maintenance
CAUTION
■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 burning, get medical atten-
tion 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. Get emergency medical attention imme-
diately.
■When replacing the 12-volt battery
Use a 12-volt battery designed for this vehicle. Failure to do so may cause gas
(hydrogen) to enter the passenger compartment, causing a fire or explosion.
For replacement of the 12-volt battery, contact your Lexus dealer.
NOTICE
■When recharging the 12-volt battery
Never recharge the 12-volt battery while the hybrid system is operating. Also, be
sure all accessories are turned off.
GS450h_U.book Page 650 Monday, January 23, 2012 10:20 AM
Page 669 of 862
668
GS450h_U (OM30D01U)
6-3. Do-it-yourself maintenance
Electronic key battery
●Flathead screwdriver
●Small flathead screwdriver
●Lithium battery CR2032
Take out the mechanical key.
Remove the cover.
To prevent damage to the key, cover
the tip of the screwdriver with a rag.
Remove the depleted battery.
Insert a new battery with the “+” termi-
nal facing up.
Replace the battery with a new one if it is depleted.
You will need the following items:
Replacing the battery
1
2
3
GS450h_U.book Page 668 Monday, January 23, 2012 10:20 AM
Page 670 of 862

GS450h_U (OM30D01U)
6696-3. Do-it-yourself maintenance
6
Maintenance and care
■Use a CR2032 lithium battery
●Batteries can be purchased at your Lexus dealer, local electrical appliance shops
or camera stores.
●Replace only with the same or equivalent type recommended by the manufacturer.
●Dispose of used batteries according to local laws.
■If the electronic key battery is depleted
The following symptoms may occur:
●The smart access system with push-button start and wireless remote control will
not function properly.
●The operational range will be reduced.
CAUTION
■Removed battery and other parts
Keep away from children. These parts are small and if swallowed by a child, they
can cause choking. Failure to do so could result in death or serious injury.
NOTICE
■For normal operation after replacing the battery
Observe the following precautions to prevent accidents:
●Always work with dry hands.
Moisture may cause the battery to rust.
●Do not touch or move any other component inside the remote control.
●Do not bend either of the battery terminals.
GS450h_U.book Page 669 Monday, January 23, 2012 10:20 AM