2010 Lexus GS450h battery

495
4-3. Do-it-yourself maintenance
4
Maintenance and care
GS_HV_U (OM30C81U)
October 13, 2015 12:41 pm
■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 your Lexus
dealer.
●Dispose of used batteries according to the local laws.
■When the card key battery needs to be replaced
The battery for the card key is available only at Lexus dealers. Your Lexus dealer
can replace the battery for you.
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 components inside the electronic key.
●Do not bend the battery terminals.

501
4-3. Do-it-yourself maintenance
4
Maintenance and care
GS_HV_U (OM30C81U)
October 13, 2015 12:41 pm
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, 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

When trouble arises5
521
GS_HV_U (OM30C81U)
January 28, 2010 11:33 am
5-1. Essential information
Emergency flashers............... 522
If your vehicle needs 
to be towed ............................ 523
If you think something is 
wrong ....................................... 531
Event data recorder .............. 5325-2. Steps to take in an 
emergency
If a warning light turns 
on or a warning buzzer 
sounds..................................... 534
If a warning message is 
displayed................................ 543
If you have a flat tire (Vehicles 
with standard tires) ............. 560
If you have a flat tire (Vehicles 
with run-flat tires)................ 570
If the hybrid system will 
not start .................................. 572
If the shift lever cannot be 
shifted from “P”.................... 573
If you lose your keys ............... 574
If the electronic key does not 
operate properly .................. 575
If the 12 volt battery is 
discharged ............................ 578
If your vehicle overheats ...... 581
If the vehicle becomes 
stuck........................................ 584
If your vehicle has to be stopped 
in an emergency .................. 586

522
GS_HV_U (OM30C81U)
January 28, 2010 10:42 am
5-1. Essential information
Emergency flashers
NOTICE
■To prevent 12 volt battery discharge
Do not leave the emergency flashers on longer than necessary when the hybrid sys-
tem is off.
Use the emergency flashers if the vehicle malfunctions or is involved in an
accident.
Press the switch to flash all the
turn signal lights. To turn them
off, press the switch once again.

552
5-2. Steps to take in an emergency
GS_HV_U (OM30C81U)
October 13, 2015 12:41 pm
Wa r n i n g m e s s a g eDetailsCorrection procedure
(Flashing)
The hybrid battery (trac-
tion battery) is low.
• If a buzzer sounds inter-
mittently, stop the vehicle
in a safe place and shift
lever to P to charge the
hybrid battery (traction
battery).
• If a buzzer sounds con-
tinuously, immediately
stop the vehicle in a safe
place. 
Turn the “POWER”
switch off and then to
ON mode to restart the
hybrid system. Ensuring
the shift lever is in P,
charge the hybrid bat-
tery (traction battery).
(Flashing)
The gasoline engine can-
not operate or the shift
lever is in “N” for a long
time.
Stop the vehicle and shift
the shift lever to “P”.
(Flashing)
The transmission is out of
“P” when attempting to
start the hybrid system.Shift the shift lever to “P”
before pressing the power
switch.

558
5-2. Steps to take in an emergency
GS_HV_U (OM30C81U)
October 13, 2015 12:41 pm
Interior
buzzerExterior
buzzerWa r n i n g m e s s a g eDetailsCorrection
procedure
Once(Comes on for 10 seconds)
(Flashing)
The electronic key
battery is low.Replace the
battery.
(P. 4 9 4 )

An open door has
been closed and
the “POWER”
switch has been
turned twice to
the ACCES-
SORY mode from
OFF.
Press the
“POWER”
switch while
applying the
brakes.

(Flashing)
The steering lock
has not released
within 3 seconds
of pressing the
“POWER” switch.
The “POWER”
switch indicator
will flash green for
15 seconds.Press the
“POWER”
switch again
while turn-
ing the
steering
wheel with
the brake
pedal
depressed.

572
5-2. Steps to take in an emergency
GS_HV_U (OM30C81U)
October 13, 2015 12:41 pm
If the hybrid system will not start
If the hybrid system will not start even though correct starting procedures
are being followed (
P. 150), consider each of the following points.
■The hybrid system will not start even 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. 575)
●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 immobilizer system. (P. 99)
■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. 5 7 8 )
●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. 5 7 8 )
Contact your Lexus dealer if the problem cannot be repaired, or if
repair procedures are unknown.

5
When trouble arises
575
5-2. Steps to take in an emergency
GS_HV_U (OM30C81U)
October 13, 2015 12:41 pm
If the electronic key does not operate properly
Locking and unlocking the doors, unlocking the trunk and key linked
functions
Doors
Using the mechanical key (
P. 37)
in order to perform the following
operations:
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)
If communication between the electronic key and vehicle is interrupted
(
P. 45) or the electronic key cannot be used because the battery is
depleted, the smart access system with push-button start and wireless
remote control cannot be used. In such cases, the doors and trunk can be
opened or the hybrid system can be started by following the procedure
below.