Page 827 of 1014
803 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30D53E_(EE)
Light bulbs
Check the wattage of the light bulb to be replaced. (P. 939)
P. 740
Front
Vehicles with discharge headlights
You may replace the following bulbs by yourself. The difficulty
level of replacement varies depending on the bulb. As there is a
danger that components may be damaged, we recommend that
replacement is carried out by any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
Preparing for light bulb replacement
Removing the engine compartment covers
Bulb locations
Front turn signal light
Halogen front fog light (if equipped)1
2
Page 856 of 1014

829
7 7-2. Steps to take in an emergency
When trouble arises
GS450h_300h_OM_OM30D53E_(EE)
If you think something is wrong
Fluid leaks under the vehicle.
(Water dripping from the air conditioning after use is normal.)
Flat-looking tires or uneven tire wear
Engine coolant temperature gauge needle continually points
higher than normal.
Changes in exhaust sound
Excessive tire squeal when cornering
Strange noises related to the suspension system
Pinging or other noises related to the hybrid system
Engine missing, stumbling or running roughly
Appreciable loss of power
Vehicle pulls heavily to one side when braking
Vehicle pulls heavily to one side when driving on a level road
Loss of brake effectiveness, spongy feeling, pedal almost
touches the floor
If you notice any of the following symptoms, your vehicle proba-
bly needs adjustment or repair. Contact any authorized Lexus
dealer or repairer, or another duly qualified and equipped profes-
sional as soon as possible.
Visible symptoms
Audible symptoms
Operational symptoms
Page 858 of 1014

8317-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30D53E_(EE)
The following warning indicates the possibility of damage to the
vehicle that may lead to an accident. Immediately stop the vehicle
in a safe place and contact any authorized Lexus dealer or repairer,
or another duly qualified and equipped professional.
Failure to investigate the cause of the following warnings may lead
to the system operating abnormally and possibly cause an accident.
Have the vehicle inspected by any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional imme-
diately.
Stop the vehicle immediately.
Wa r n i n g
lightWarning light/Details
Charging system warning light
Indicates a malfunction in the vehicle’s charging system
Have the vehicle inspected by any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional
immediately.
Wa r n i n g
lightWarning light/Details
Malfunction indicator lamp
Indicates a malfunction in:
• The hybrid system;
• The emission control system (if equipped);
• The electronic engine control system;
• The electronic throttle control system; or
• The electronic hybrid transmission control system (if
equipped)
SRS warning light
Indicates a malfunction in:
• The SRS airbag system; or
• The seat belt pretensioner system
Page 868 of 1014
8417-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30D53E_(EE)
A buzzer sounds and a warning message is shown on the multi-
information display. The following warning indicates the possibil-
ity of damage to the vehicle that may lead to an accident. Immedi-
ately stop the vehicle in a safe place and contact any authorized
Lexus dealer or repairer, or another duly qualified and equipped
professional.
Stop the vehicle immediately.
Wa r n i n g m e s s a g eDetails
Indicates abnormal engine oil pressure
The warning light may come on if the engine
oil pressure is too low.
Indicates a malfunction in the hybrid system
or
Page 879 of 1014
8527-2. Steps to take in an emergency
GS450h_300h_OM_OM30D53E_(EE)
Indicates that the
hybrid battery (trac-
tion battery) is low
When stopping the
vehicle for a long
period of time, shift the
shift lever to P. The
battery cannot be
charged with the shift
lever in N.
Indicates that the
hybrid battery (trac-
tion battery) power has
dropped because a long
period of time has
elapsed after shifting
the shift lever to N
Restart the hybrid sys-
tem when starting the
vehicle.
Indicates that the gaso-
line engine cannot
operate or the shift
lever is in N for a long
time
Stop the vehicle and
shift the shift lever to P.
Indicates that the accel-
erator pedal is
depressed while the
shift position is in NRelease the accelerator
pedal and shift the shift
lever to D, S or R.
Wa r n i n g m e s s a g eDetailsCorrection procedure
(Flashes)
(Flashes)
(Flashes)
(Flashes)
Page 880 of 1014
8537-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30D53E_(EE)
*: For the EV drive mode operating conditions: P. 254
Indicates that the EV
drive mode is not avail-
able
*
The reason the EV
drive mode is not
available (the vehi-
cle is idling, battery
charge is low, speed
is higher than the EV
drive mode operat-
ing speed range,
accelerator pedal is
depressed too much)
may be displayed.
Use the EV drive mode
when it becomes avail-
able.
Indicates that the EV
drive mode has been
automatically can-
celed
*
The reason the EV
drive mode is not
available (the battery
charge is low, speed
is higher than the EV
drive mode operat-
ing speed range,
accelerator pedal is
depressed too much)
may be displayed.
Drive the vehicle for a
while.
Indicates that engine
oil level is lowCheck the level of
engine oil, and add if
necessary.
Wa r n i n g m e s s a g eDetailsCorrection procedure
Page 883 of 1014
8567-2. Steps to take in an emergency
GS450h_300h_OM_OM30D53E_(EE)
(If equipped)
Indicates that the LKA
(Lane-Keeping Assist)
system detects no-
handed driving (while
the lane keeping assist
function is operating)
The warning buzzer
sounds twice.
Grip the steering wheel
firmly.
(If equipped)
Indicates that the Blind
Spot Monitor sensors
or the surrounding area
on the bumper is dirty
or covered with ice
Clean the sensor and its
surrounding area on the
bumper.
Indicates that the
hybrid system has
overheated
This message may be
displayed when driv-
ing under severe
operating condi-
tions. (For example,
when driving up a
long steep hill.)
Stop and check.
(P. 917)
Indicates that the
hybrid system output is
limited because the
engine oil is over-
heatedDrive the vehicle at a
safe speed until the
warning message dis-
appears.
Wa r n i n g m e s s a g eDetailsCorrection procedure
Page 895 of 1014
8687-2. Steps to take in an emergency
GS450h_300h_OM_OM30D53E_(EE)
Inte-
rior
buzzerExterior
buzzerWarning messageDetailsCorrection
procedure
Power was turned
off due to the
automatic power
off function.
Next time
when start-
ing the
hybrid sys-
tem,
increase
the engine
speed
slightly
and main-
tain that
level for
approxi-
mately 5
minutes to
recharge
the 12-volt
battery.
Once
The electronic
key has a low bat-
tery.
Replace
the elec-
tronic key
battery.
(P. 779)