engine Lexus GS300h 2013 Workshop Manual

7446-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
The coolant level is satisfactory if it is between the “FULL” and
“LOW” lines on the reservoir when the hybrid system is cold.
Engine coolant reservoir
Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the “LOW” line, add coolant up to the
“FULL” line. (P. 915)
Coolant
GS300hGS450h
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7466-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
Coolant selection
Only use “Toyota Super Long Life Coolant” or a similar high quality eth-
ylene glycol based non-silicate, non-amine, non-nitrite, and non-borate cool-
ant with long-life hybrid organic acid technology.
“Toyota Super Long Life Coolant” is a mixture of 50% coolant and 50%
deionized water. (Minimum temperature: -35C [-31F])
For more details about coolant, contact any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
If the coolant level drops within a short time of replenishing
Visually check the radiator, hoses, engine/power control unit coolant reser-
voir caps, drain cock and water pump.
If you cannot find a leak, have any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional, test the cap and check for
leaks in the cooling system.
CAUTION
When the hybrid system is hot
Do not remove the engine/power control unit coolant reservoir caps or the
coolant inlet cap. (P. 9 2 1 )
The cooling system may be under pressure and may spray hot coolant if the
cap is removed, causing serious injuries, such as burns.
NOTICE
When adding coolant
Coolant is neither plain water nor straight antifreeze. The correct mixture of
water and antifreeze must be used to provide proper lubrication, corrosion
protection and cooling. Be sure to read the antifreeze or coolant label.
If you spill coolant
Be sure to wash it off with water to prevent it from damaging parts or paint.

7486-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
If any washer does not work or
the warning message appears on
the multi-information display,
the washer tank may be empty.
Add washer fluid.
Washer fluid
CAUTION
When adding washer fluid
Do not add washer fluid when the hybrid system is hot or operating as
washer fluid contains alcohol and may catch fire if spilled on the engine
etc.
NOTICE
Do not use any fluid other than washer fluid
Do not use soapy water or engine antifreeze instead of washer fluid.
Doing so may cause streaking on the vehicle’s painted surfaces.
Diluting washer fluid
Dilute washer fluid with water as necessary.
Refer to the freezing temperatures listed on the label of the washer fluid
bottle.

7826-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30D53E_(EE)
Checking and replacing fuses
Turn the power switch off.
After a system failure, see “Fuse layout and amperage ratings”
for details about which fuse to check. (P. 787)
Open the fuse box cover.
Engine compartment:
Remove the engine compart-
ment cover (P. 740) and
remove all of the clips.
Push the tabs on either side to
detach the lock and lift the lid
off while pulling the lock
plate.
When installing the lid, check
that the lock plate and the tabs
on either side are connected cor-
rectly.
If any of the electrical components do not operate, a fuse may have
blown. If this happens, check and replace the fuses as necessary.
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787 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30D53E_(EE)
Engine compartment
Fuse layout and amperage ratings
FuseAmpereCircuit
1IGN10Starting system
2INJ10Multiport fuel injection system/sequen-
tial multiport fuel injection system
3EFI NO.210Air intake system, exhaust system
4IG2 MAIN20IGN, GAUGE, INJ, AIR BAG, IG2
NO.1, LH-IG2
5EFI MAIN25
Multiport fuel injection system/sequen-
tial
multiport fuel injection system, EFI
NO.2
6A/F15Air flow sensor
7EDU20Multiport fuel injection system/sequen-
tial multiport fuel injection system

801 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30D53E_(EE)
The upper part of the 12-volt battery*
*: When one or more of the fuses in this unit are blown, the unit needs to be
replaced as a whole.
FuseAmpereCircuit
1EPB30Parking brake
2LUG-J/B BATT40Luggage compartment junction block
3EPS80Electric power steering
4ARS80Dynamic Rear Steering
5MAIN220Engine compartment junction block

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
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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

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

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