2007 Lexus GS450h key battery

Maintenance and care4
351
4-1. Maintenance and care ........ 352Cleaning and protecting the 
vehicle exterior........................ 352
Cleaning and protecting the 
vehicle interior......................... 354 4-2. Maintenance........................... 357
Maintenance requirements............................ 357
General maintena nce ............. 359
Emission inspection and 
maintenance (I/M) 
programs ................................... 362
4-3. Do-it-yourself 
maintenance......................... 363
Do-it-yourself service 
precautions ............................... 363
Hood .............................................. 366
Positioning the jack .................. 367
Engine compartment .............. 369
Tires ................................................. 383
Tire inflation pressure .............. 393
Wheels .......................................... 397
Air conditioning filter .............. 399
Electronic key battery .............. 401
Checking and replacing 
fuses ............................................. 403
Headlight aim .............................. 419
Light bulbs...................................... 421

401
4-3. Do-it-yourself maintenance
4
Maintenance and care
Electronic key battery
Replace the battery with a new one if it is discharged.
■You will need the following items:
●Flathead screwdriver
● Small Phillips-head sc rewdriver
● Lithium battery (CR1632)
■ Replacing the battery
Take out the mechanical key.
Remove the cover.
Remove the depleted battery.
Insert a new battery with the “+”
terminal facing up.
STEP1
STEP2
STEP3

402
4-3. Do-it-yourself maintenance
■If the electronic key battery is discharged
The following symptoms may occur.
●The smart access system with push-button start and wireless remote control will
not function properly.
●The operational range is reduced.
■Use a CR1632 lithium battery
●Batteries can be purchased at your Lexus dealer, jewelers, or camera stores.
●Replace only with the same or equivalent type recommended by a Lexus dealer.
●Dispose of used batteries according to the local laws.
CAUTION
■Removed battery and other parts
Keep away from children. 
These parts are small and if swallowed by a child they can cause choking.
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 comp onents inside the electronic key.
●Do not bend the battery terminals.

When trouble arises5
427
5-1. Essential information............ 428If your vehicle needs to be 
towed .......................................... 428
If you think something is 
wrong .......................................... 435
Event data recorder ................. 436
5-2. Steps to take in an 
emergency............................ 438
If a warning light turns on or a 
warning buzzer sounds............ 438
If a warning message is 
displayed.................................... 444
If you have a flat tire (Vehicles 
with run-flat tires) ................... 460
If you have a flat tire (Vehicles 
with standard tires) .................. 461
If the hybrid system will not 
start ................................................ 471
If the shift lever cannot be 
shifted from P............................ 472
If you lose your keys .................. 473
When the electronic key 
battery is discharged ............. 474
If the 12 volt battery is 
discharged ................................. 476
If your vehicle overheats ....... 480
If the vehicle becomes  stuck ............................................ 483

458
5-2. Steps to take in an emergency
InteriorbuzzerExterior buzzerWa r n i n g m e s s a g eDetailsCorrection procedure
Once3 times
(Flashing)
An open door
other than the
driver's door is
closed while the
electronic key is
outside the detec-
tion range and the
power switch is in
“ACC” or “IG-
ON” mode with
the shift lever in
“P”.
Tu r n t h e
power
switch
“OFF” or
confirm the
location of
the elec-
tronic key.
Contin-
uousContin-
uous
(Displayed alternately)
(Flashing)
An open door
other than the
driver's door is
closed while the
electronic key is
outside the detec-
tion range and the
power switch is in
“ACC” or “IG-
ON” mode with
the shift lever not
in “P”.
•Shift the shift lever
to “P”.
•Confirm the loca-
tion of the
electronic
key.
Once
(Flashing)
The electronic key
battery is low.Replace the
battery.
( P. 4 0 1 )

5
When trouble arises
471
5-2. Steps to take in an emergency
If the hybrid system will not start
If the hybrid system will not start even though correct starting procedures
are being followed (
P. 103), consider each of the following points.
■The hybrid system will not start ev en if you are carrying the cor-
rect electronic key
One of the following may be the cause of the problem.
● The electronic key battery may be discharged. ( P. 17)
● There may not be sufficient fuel in the vehicle’s tank. 
Add fuel to the vehicle.
● There may be a malfunction in the steering lock system.
● There may be a malfunction in the hybrid vehicle immobilizer sys-
tem. 
( P. 5 9 )
■ The interior lights and headlights are dim, or the horn does not
sound or sounds at a low volume
One of the following may be the cause of the problem.
● The 12 volt battery may be discharged. ( P. 4 76 )
● The 12 volt battery terminal connections may be loose or cor-
roded.
■ The interior lights and headlights do not turn on, or the horn does
not sound
One of the following may be the cause of the problem.
●One or both of the 12 volt battery terminals may be discon-
nected.
● The 12 volt battery may be discharged. ( P. 4 76 )
Contact your Lexus dealer if the problem cannot be repaired, or if
repair procedures are unknown.

474
5-2. Steps to take in an emergency
When the electronic key battery is discharged
Locking and unlocking the doors, unlocking the trunk and key linked functions
DoorsUsing the mechanical key in order
to perform the following opera-
tions:
Locks all doors
Closes the windows/moon roof
(turn and hold)
Unlocks the door
Turning the key rearward unlocks
the driver's door. Turning the key
once again unlocks the other
doors.
Opens the windows/moon roof
(turn and hold)
Tr u n k
Turn the mechanical key clock-
wise to open.
If the electronic key battery is di scharged, the doors and trunk can be
opened by the mechanical key. The hybrid system can be still started by fol-
lowing the procedure.

5
When trouble arises
475
5-2. Steps to take in an emergency
Starting the hybrid systemPut the shift lever in “P” and apply the brakes. Hold the electronic key close to
the power switch (within 0.4 in. [10
mm]). Make sure that the button
side of the key is facing away from
the power switch.
An alarm will sound to indicate that
the start function cannot detect the
key with the depleted battery if any
of the doors will be opened and
closed while this operation.
Press the power switch within 5 seconds after the buzzer sounds,
keeping the brake pedal depressed.
If the hybrid system still cannot be started, contact your Lexus dealer.
STEP1
STEP2
■Replacing the key battery
As this procedure is the temporary measure, it is recommended that the electronic
key battery be replaced immediately. ( P. 4 0 1 )
STEP3