Page 819 of 1014
795 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30D53E_(EE)
14HAZ15Turn signal lights, emergency flashers
15LH-IG210
Multiport fuel injection system/sequen-
tial multiport fuel injection system, stop
lights, smart entry & start system, steer-
ing lock system, brake system, power
management system
16LH J/B-B7.5Body ECU
17S/ROOF20Moon roof
18P/SEAT2 F/L25Power seats
19A/C7.5Air conditioning system
FuseAmpereCircuit
Page 822 of 1014
7986-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
Right-hand drive vehicles
FuseAmpereCircuit
1STOP7.5Stop lights, high mounted stoplight
2P/SEAT1 F/R30Power seats
3FR P/OUTLET15Power outlet (front)
4P/W-B5Power window master switch
5RR P/OUTLET15Power outlet (rear)
6P/SEAT2 F/R25Power seats
7AV S20AV S
8WIPER30Windshield wipers
9WA S H20Windshield washer
10RH ECU-IG10
Navigation system, VGRS, Lexus night
view, brake system, D-SW MODULE
(Blind Spot Monitor, heated steering
wheel), pre-crash seat belts, DRS
11RH-IG10
Tension reducer, power seats, head-up
display, front right-hand door ECU,
“nanoe™”, shift lock system, electric tilt
and telescopic steering column, seat
heater/ventilator switches, smart entry &
start system antennas, tire pressure warn-
ing system receiver, driver monitor sys-
tem
12DOOR FR30
Front right-hand door control system
(outside rear view mirror defoggers,
power window)
Page 845 of 1014

819
7When trouble arises
GS450h_300h_OM_OM30D53E_(EE)7-1. Essential information
Emergency flashers ........... 820
If your vehicle
has to be stopped
in an emergency .............. 8217-2. Steps to take in an emergency
If your vehicle needs
to be towed ..................... 822
If you think something
is wrong .......................... 829
If a warning light turns on
or a warning buzzer
sounds ............................. 830
If a warning message
is displayed ..................... 838
If you have a flat tire (vehicles
with a spare tire) ............. 870
If you have a flat tire (vehicles
without a spare tire) ........ 884
If the hybrid system
will not start .................... 902
If the shift lever cannot be
shifted from P ................. 904
If the parking brake
cannot be released........... 905
If the electronic key does not
operate properly .............. 908
If the 12-volt battery
is discharged ....................911
If your vehicle overheats .. 915
If the vehicle
becomes stuck................. 923
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 888 of 1014
8617-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30D53E_(EE)
(If equipped)
Indicates that the tire
position information
cannot be recognized
Drive for a short while
and check if the display
updates.
If the radio wave
conditions improve,
the display may
return to normal. If
the tire pressure is
still not displayed
after driving for sev-
eral minutes, stop the
vehicle in a safe
place, turn the power
switch off then on
again, and start driv-
ing.
If the tire pressure is
still not displayed
even after repeating
this several times,
have the vehicle
inspected by any
authorized Lexus
dealer or repairer, or
another duly quali-
fied and equipped
professional.
Wa r n i n g m e s s a g eDetailsCorrection procedure
Page 939 of 1014

9127-2. Steps to take in an emergency
GS450h_300h_OM_OM30D53E_(EE)
Stopping the hybrid system
Shift the shift lever to P and press the power switch as you normally do when
stopping the hybrid system.
Replacing the key battery
As the above procedure is a temporary measure, it is recommended that the
electronic key battery be replaced immediately when the battery is depleted.
(P. 779)
Alarm (if equipped)
Using the mechanical key to lock the doors will not set the alarm system.
If a door is unlocked using the mechanical key when the alarm system is set,
the alarm may be triggered.
Changing power switch modes
Release the brake pedal and press the power switch in step above.
The hybrid system does not start and modes will be changed each time the
switch is pressed.(P. 247)
When the electronic key does not work properly
Make sure that the smart entry & start system has not been deactivated in
the customization setting. If it is off, turn the function on.
(Customizable features: P. 942)
Check if battery-saving mode is set. If it is set, cancel the function. (P.
149)
3
Page 946 of 1014
9197-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30D53E_(EE)
Add coolant if necessary. (P. 923)
Water can be used in an emergency if engine coolant is unavailable.
Start the hybrid system and turn the air conditioning system on
to check that the radiator cooling fans operate and to check for
coolant leaks from the radiator or hoses.
The fans operate when the air conditioning system is turned on immedi-
ately after a cold start. Confirm that the fans are operating by checking
the fan sound and air flow. If it is difficult to check these, turn the air
conditioning system on and off repeatedly. (The fans may not operate in
freezing temperatures.)
If the fans are not operating:
Stop the hybrid system immediately and contact your Lexus
dealer.
If the fans are operating:
Have the vehicle inspected at the nearest Lexus dealer.
5
GS300hGS450h
6
7
Page 949 of 1014
9227-2. Steps to take in an emergency
GS450h_300h_OM_OM30D53E_(EE)
Add coolant if necessary.
Water can be used in an emergency if power control unit coolant is
unavailable.
Start the hybrid system and check for the multi-information
display.
If the message does not disappear:
Stop the hybrid system and contact your Lexus dealer.
If the message is not displayed:
Have the vehicle inspected at the nearest Lexus dealer.
5
GS300hGS450h
6