warning light Lexus GS300h 2013 Owner's Guide

7566-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
Your vehicle is equipped with a tire pressure warning system that
uses tire pressure warning valves and transmitters to detect low tire
inflation pressure before serious problems arise.
Vehicles without the tire inflation pressure display function
If the tire pressure drops below a predetermined level, the driver is
warned by a warning light. (P. 834)
Vehicles with the tire inflation pressure display function
If the tire pressure drops below a predetermined level, the driver
is warned by a screen display and a warning light. (P. 859)
The tire pressure detected by the tire pressure warning system
can be displayed on the multi-information display. (P. 117)
Installing tire pressure warning valves and transmitters
When replacing tires or wheels, tire pressure warning valves and
transmitters must also be installed.
When new tire pressure warning valves and transmitters are
installed, new ID codes must be registered in the tire pressure
warning computer and the tire pressure warning system must be
initialized. Have tire pressure warning valve and transmitter ID
codes registered by any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional. (P. 758)
Tire pressure warning system (if equipped)

7586-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
Press and hold the tire pres-
sure warning reset switch
until the tire pressure warn-
ing light blinks slowly 3
times.
Wait for a few minutes with the power switch in ON mode and
then turn the power switch off.
Registering ID codes
The tire pressure warning valve and transmitter is equipped with
a unique ID code. When replacing a tire pressure warning valve
and transmitter, it is necessary to register the ID code. Have the
ID code registered by any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
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5

759 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30D53E_(EE)
When to replace your vehicle’s tires
Tires should be replaced if:
You have tire damage such as cuts, splits, cracks deep enough to expose the
fabric, and bulges indicating internal damage
A tire goes flat repeatedly or cannot be properly repaired due to the size or
location of a cut or other damage
If you are not sure, consult with any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
Replacing tires and wheels (vehicles with the tire pressure warning system)
If the ID code of the tire pressure warning valve and transmitter is not regis-
tered, the tire pressure warning system will not work properly. After driving
for about 10 minutes, the tire pressure warning light blinks for 1 minute and
stays on to indicate a system malfunction.
Tire life
Any tire over 6 years old must be checked by a qualified technician even if it
has seldom or never been used or damage is not obvious.
Routine tire inflation pressure checks
The tire pressure warning system does not replace routine tire inflation pres-
sure checks. Make sure to check tire inflation pressure as part of your routine
of daily vehicle checks.
When rotating the tires (vehicles with the tire pressure warning system featur-
ing a tire inflation pressure display function)
Make sure that the power switch is off. If the tires are rotated while the power
switch is in ON mode, the tire position information will not be updated.
If this accidentally occurs, either turn the power switch to off and then to ON
mode, or initialize the system after checking that the tire pressure is properly
adjusted.

761 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30D53E_(EE)
The initialization operation (vehicles with the tire pressure warning system)
Make sure to carry out initialization after adjusting the tire inflation pres-
sure.
Also, make sure the tires are cold before carrying out initialization or tire
inflation pressure adjustment.
If you have accidentally turned the power switch off during initialization, it
is not necessary to press the reset switch again as initialization will restart
automatically when the power switch has been turned to ON mode for the
next time.
If you accidentally press the reset switch when initialization is not neces-
sary, adjust the tire inflation pressure to the specified level when the tires
are cold, and conduct initialization again.
Warning performance of the tire pressure warning system (if equipped)
The warning of the tire pressure warning system will change in accordance
with the conditions under which it was initialized. For this reason, the system
may give a warning even if the tire pressure does not reach a low enough
level, or if the pressure is higher than the pressure that was adjusted to when
the system was initialized.
When initialization of the tire pressure warning system has failed (vehicles
with the tire pressure warning system)
Initialization can be completed in a few minutes. However, in the following
cases, the settings have not been recorded and the system will not operate
properly. If repeated attempts to record tire inflation pressure settings are
unsuccessful, have the vehicle inspected by any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
When operating the tire pressure warning reset switch, the tire pressure
warning light does not blink 3 times.
After carrying out the initialization procedure, the tire pressure warning
light blinks for 1 minute then stays on after driving for 20 minutes.
Registering ID codes (vehicles with the tire pressure warning system)
The ID codes of the tire pressure warning valve and transmitters for two sets
of wheels can be registered.
It is not necessary to register the ID codes when replacing normal tires with
snow tires, if the ID codes for the wheels of both normal tires and snow tires
are registered beforehand.
For information about changing ID codes, ask any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.

7686-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
CAUTION
When inspecting or replacing tires
Observe the following precautions to prevent accidents.
Failure to do so may cause damage to parts of the drive train as well as dan-
gerous handling characteristics, which may lead to an accident resulting in
death or serious injury.
Do not mix tires of different makes, models or tread patterns.
Also, do not mix tires of remarkably different treadwear.
Do not use tire sizes other than those recommended by Lexus.
Do not mix differently constructed tires (radial, bias-belted or bias-ply
tires).
Do not mix summer, all season and snow tires.
Do not use tires that have been used on another vehicle.
Do not use tires if you do not know how they were used previously.
Vehicles with a compact spare tire: Do not tow if your vehicle has a com-
pact spare tire installed.
Vehicles with an emergency tire puncture repair kit (if equipped): Do not
tow anything if a tire that has been repaired using the emergency tire
puncture repair kit is installed. The load on the tire may cause unexpected
damage to the tire.
When initializing the tire pressure warning system (vehicles with the tire
pressure warning system)
Do not operate the tire pressure warning reset switch without first adjusting
the tire inflation pressure to the specified level. Otherwise, the tire pressure
warning light may not come on even if the tire inflation pressure is low, or
it may come on when the tire inflation pressure is actually normal.

8006-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
Trunk
FuseAmpereCircuit
1PSB30Pre-crash seat belts
2PTL25Power trunk lid
3RR J/B-B10Smart entry & start system
4RR S/HTR20Seat heaters (rear)
5FR S/HTR10Seat heaters/ventilators (front)
6RR FOG10Rear fog light
7DC/DC-S (HV)7.5DC/DC converter
8BATT FAN (HV)20Hybrid battery (traction battery) cooling
fan system
9SECURITY7.5SECURITY
10ECU-B NO.37.5Parking brake
11TRK OPN7.5Power trunk lid, trunk open motor
12DCM (HV)7.5No circuit
13AC INV (HV)20No circuit
14RR-IG15Radar sensor, Blind Spot Monitor
15RR ECU-IG10
Power trunk lid, parking brake, tension
reducer (rear left-hand), RR CTRL SW,
tire pressure warning system
16EPS-IG5Electric power steering system
17BACK UP7.5Back-up light

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

8307-2. Steps to take in an emergency
GS450h_300h_OM_OM30D53E_(EE)
If a warning light turns on or a warning buzzer
sounds
The following warning indicates a possible problem in the brake
system. Immediately stop the vehicle in a safe place and contact
any authorized Lexus dealer or repairer, or another duly qualified
and equipped professional.
Calmly perform the following actions if any of the warning lights
comes on or flashes. If a light comes on or flashes, but then goes
off, this does not necessarily indicate a malfunction in the system.
However, if this continues to occur, have the vehicle inspected by
any authorized Lexus dealer or repairer, or another duly qualified
and equipped professional.
Stop the vehicle immediately. Continuing to drive the vehicle
may be dangerous.
Wa r n i n g
lightWarning light/Details
Brake system warning light (warning buzzer)
• Low brake fluid
• Malfunction in the electronically controlled brake sys-
tem

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

8327-2. Steps to take in an emergency
GS450h_300h_OM_OM30D53E_(EE)
ABS warning light
Indicates a malfunction in:
• The ABS; or
• The brake assist system
Wa r n i n g
lightWarning light/Details