2017 Lexus GS300h engine

3926-1. Maintenance and care
GS450h_300h_OM_OM30F92E_(EE)
WARNING
■When washing the vehicle
Do not apply water to the inside of the engine compartment. Doing so may cause the
electrical components etc. to catch fire.
■When cleaning the windshield (vehicles with rain-sensing windshield wipers)
●When the upper part of the windshield where the raindrop sensor is located is
touched by hand
●When a wet rag or similar is held close to the raindrop sensor
●If something bumps against the windshield
●If you directly touch the raindrop sensor body or if something bumps into the raindrop
sensor
■Precautions regarding the exhaust pipes
Exhaust gases cause the exhaust pipes to become quite hot.
When washing the vehicle, be careful not to touch the pipes until they have cooled suf-
ficiently, as touching hot exhaust pipes can cause burns.
■Precaution regarding the rear bumper with Blind Spot Monitor (if equipped)
If the paint of the rear bumper is chipped or scratched, the system may malfunction. If
this occurs, consult any authorized Lexus re tailer or Lexus authorized repairer, or any
reliable repairer.
Turn off AUTO mode of the wiper to prevent the wiper from operating. ( P. 251)
If AUTO mode is selected, the wipers may
operate unexpectedly in the following situa-
tions, and may result in hands being caught or
other serious injuries and cause damage to the
wiper blades.

3986-2. Maintenance
GS450h_300h_OM_OM30F92E_(EE)
■Does your vehicle need repairs?
Be on the alert for changes in performance and sounds, and visual tip-offs that indicate
service is needed. Some important clues are:
●Engine missing, stumbling or pinging
●Appreciable loss of power
●Strange engine noises
●A fluid leak under the vehicle (However, water dripping from the air conditioning sys-
tem after use is normal.)
●Change in exhaust sound (This may indicate a dangerous carbon monoxide leak. Drive
with the windows open and have the exhaust system checked immediately.)
●Flat-looking tires, excessive tire sque al when cornering, uneven tire wear
●Vehicle pulls to one side when driven straight on a level road
●Strange noises related to suspension movement
●Loss of brake effectiveness, spongy feeling brake pedal, pedal almost touches the floor,
vehicle pulls to one side when braking
●Engine coolant temperature continually higher than normal ( P. 105)
If you notice any of these clues, take your vehicle to any authorized Lexus retailer or
Lexus authorized repairer, or any reliable repairer as soon as possible. Your vehicle may
need adjustment or repair.
WARNING
■If your vehicle is not properly maintained
Improper maintenance could result in serious damage to the vehicle and possible
death or serious injury.
■Handling of the 12-volt battery
12-volt battery posts, terminals and related accessories contain lead and lead com-
pounds which are known to cause brain damage. Wash your hands after handling. (  P. 412)

4006-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30F92E_(EE)
WARNING
The engine compartment contains many mech anisms and fluids that may move suddenly,
become hot, or become electrically energize d. To avoid death or serious injury, observe
the following precautions.
■When working on the engine compartment
●Make sure that the “POWER ON” on the multi-information display and the
“READY” indicator are both off.
●Keep hands, clothing and tools away from the moving fan and engine drive belt.
●Be careful not to touch the engine, power co ntrol unit, radiator, exhaust manifold, etc.
right after driving as they may be hot. Oil and other fluids may also be hot.
●Do not leave anything that may burn easily, such as paper and rags, in the engine
compartment.
●Do not smoke, cause sparks or expose an open flame to fuel. Fuel fumes are flamma-
ble.
●Take care because brake fluid can harm your hands or eyes and damage painted sur-
faces. If fluid gets on your hands or in your eyes, flush t he affected area with clean
water immediately. If you still experience discomfort, consult a doctor.
■When working near the electric cooling fans or radiator grille
Be sure the power switch is off.
With the power switch in ON mode, the electric cooling fans may automatically start to
run if the air conditioning is on and/or the coolant temperature is high. ( P. 411)
■Safety glasses
Wear safety glasses to prevent flying or falling material, fluid spray, etc. from getting in
your eyes.
NOTICE
■If you remove the air cleaner filter
Driving with the air cleaner filter removed may cause excessive engine wear due to dirt
in the air.
■If the fluid level is low or high
It is normal for the brake fluid level to go down slightly as the brake pads wear or when
the fluid level in the accumulator is high.
If the reservoir needs frequent refillin g, it may indicate a serious problem.

403
6
6-3. Do-it-yourself maintenance
Maintenance and care
GS450h_300h_OM_OM30F92E_(EE)
Engine compartment
GS450h
■12-volt battery P. 412
Engine oil level dipstick
( P. 406)
Engine coolant reservoir ( P. 409)
Engine oil filler cap ( P. 407)
Power control unit coolant
reservoir ( P. 409) Fuse box (
P. 437)
Washer fluid tank ( P. 411)
Electric cooling fans
Condenser ( P. 411)
Radiator ( P. 411)1
2
3
4
5
6
7
8
9

4046-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30F92E_(EE)
GS300h
■12-volt battery P. 412
Power control unit coolant
reservoir ( P. 409)
Engine oil level dipstick ( P. 406)
Engine oil filler cap ( P. 407)
Engine coolant reservoir ( P. 409) Fuse box (
P. 437)
Washer fluid tank ( P. 411)
Electric cooling fans
Condenser ( P. 411)
Radiator ( P. 411)1
2
3
4
5
6
7
8
9

405
6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30F92E_(EE)
■Removing the engine compartment cover
Right-hand side
Center
■Installing the clips
Push up center portion
Insert
Press
Engine compartment cover
1
2
3
NOTICE
■Checking the engine compartment cover after installation
Make sure that the cover is securely installed in its original position.

4066-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30F92E_(EE) With the engine at operating temperature and turned off, check the oil level on
the dipstick.
■Checking the engine oil
Park the vehicle on level ground. After warming up the engine and turning
off the hybrid system, wait more than 5 minutes for the oil to drain back into
the bottom of the engine.
Holding a rag under the end, pull the dipstick out.
Wipe the dipstick clean.
Reinsert the dipstick fully.
Holding a rag under the end, pull the dipstick out and check the oil level.
Low
Normal
Excessive
The shape of the dipstick may differ depending on the type of vehicle or engine.
Wipe the dipstick and reinsert it fully.
Engine oil
1
2
GS450hGS300h
3
4
5
1
2
3
Flat dipstickNon-flat dipstick
6

407
6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30F92E_(EE)
■Adding engine oil
If the oil level is below or near the low level mark, add engine oil of th e same
type as that already in the engine.
Make sure to check the oil type and prepare the items needed before adding
oil.
Remove the oil filler cap by turning it counterclockwise.
Add engine oil slowly, checking the dipstick.
Install the oil filler cap by turning it clockwise.
■Engine oil consumption
A certain amount of engine oil will be consum ed while driving. In the following situations,
oil consumption may increase, and engine oil may need to be refilled in between oil
maintenance intervals.
●When the engine is new, for example directly after purchasing the vehicle or after
replacing the engine
●If low quality oil or oil of an inappropriate viscosity is used
●When driving at high engine speeds or with a heavy load, when towing, or when driving
while accelerating or decelerating frequently
●When leaving the engine idling for a long time, or when driving frequently through
heavy traffic
GS450hGS300h
Engine oil selection P. 550
Oil quantity (Low  Full) 1.5 L (1.6 qt., 1.3 Imp.qt.)
Items Clean funnel
1
2
3