engine Lexus HS250h 2010 Basic Information Before Operation / LEXUS 2010 HS250H (OM75006U) Workshop Manual

5
When trouble arises
507
5-2. Steps to take in an emergency
(U.S.A. only)
Indicates that the engine
oil should be changedComes on approxi-
mately 5000 miles
(8000 km) after the
engine oil is changed
(and the oil maintenance
data has been reset)
Check and change the
engine oil.
Indicates that the tire
inflation pressure is lowCheck the tire inflation
pressure, and adjust to the
appropriate level.
(If equipped)
Indicates that the pre-
collision system is not
currently functional
because the grille or the
sensor is dirty.
This message also
appears when the pre-
collision system is not
functional due to over-
heating.
Check the grille and the
sensor and clean them if
they are dirty.In case of overheating,
the system will become
functional once the sys-
tem cools down.
(If equipped)
Indicates that intuitive
parking assist sensor is
dirty or covered with ice
A buzzer also sounds.
The site of the malfunc-
tion and the vehicle
image are flashing.
Clean the sensor.
Wa r n i n g m e s s a g eDetailsCorrection procedure

518
5-2. Steps to take in an emergency

Po w e r w a s t u r n e d
off due to the
automatic power
off function.
Next time when
starting the hybrid
system, increase
the engine speed
slightly and main-
tain that level for
approximately 5
minutes to
recharge the 12-
volt battery.
OnceThe electronic key
has a low battery.Replace the elec-
tronic key battery.
(P. 4 5 3 )
Interior
buzzerExterior buzzerWa r n i n g m e s s a g eDetailsCorrection
procedure

520
5-2. Steps to take in an emergency
■Warning light display in radar cruise mode
In the following cases, the warning light may
not be displayed even if vehicle-to-
vehicle distance decreases:
●When your vehicle and the vehicle ahead are traveling at the same speed or the
vehicle ahead is traveling more quickly than your vehicle
●When the vehicle ahead is traveling at a very low speed
●Immediately after cruise control speed is set
●At the instant the accelerator pedal is depressed
■After changing the engine oil (U.S.A. only)
Make sure to reset the oil maintenance data. ( P.
4 2 6 )

5
When trouble arises
537
5-2. Steps to take in an emergency
Connect the jumper cables according to the following procedure:
Connect a positive jumper cable clamp to the exclusive jump start-
ing terminal on your vehicle
Connect the clamp on the other end of the positiv
e cable to the pos-
itive (+) battery terminal on the second v
ehicle
Connect a negative cable clamp to the negative (-) battery terminal
on the second vehicle
Connect the clamp at the other end of the negative cable to a solid,
stationary, unpainted metallic point aw
ay from the exclusive jump
starting terminal and any moving part s, as shown in the illustration.
Start the engine of the second v
ehicle. Increase the engine
speed slightly and maintain that le
vel for approximately 5 min-
utes to recharge the 12-volt battery of your vehicle.
Maintain the engine sp eed of the second v
ehicle and start the
hybrid system of your vehicle by turning the “POWER” switch
to ON mode.
Make sure the “READY” indicator comes on. If the indicator
does not come on, contact your Lexus dealer.
Once the hybrid system has star
ted, remove the jumper cables
in the exact reverse order from which they were connected.

5
When trouble arises
541
5-2. Steps to take in an emergency
If your vehicle overheats
Correction procedures
■If the engine coolant temperature warning light comes on or flashes
Stop the vehicle in a safe place an d turn of
f the air conditioning
system.
Check to see if steam is coming out from the engine area.
If you see steam: 
Stop the hybrid system. Carefu lly lif
t the hood after the steam
subsides and then restart the hybrid system.
If you do not see steam:
Leave the hybrid system operating and carefully lift the hood.
Remove the engine compartment cover. ( P. 4 2 3 )
Check to see if the cooling fans are operating.
If the fans are operating: 
Wait until the high engine coolant temperature warning light goes
of
f and then stop the hybrid system.
If the fans are not operating: 
Stop the hybrid system immediately and call your Lexus dealer.
The following may indicate that your vehicle is overheating:
●The high engine coolant temperature warning light comes on or
flashes: 
The engine may be overheating.
● “HYBRID S
YSTEM OVERHEAT” is sh own on the multi-information
display: 
The power control unit may be overheating.
Follow the correction procedure as described below.

542
5-2. Steps to take in an emergency
After the hybrid system has cooled
down sufficiently, check the engine
coolant level and inspect the cool-
ing system for leaks.
Add engine coolant if necessary.
Water can be used in an emer -
gency if engine coolant is unavail -
able. ( P. 5 5 2 )
Have the vehicle inspected at the ne arest Lexus dealer as soon as possi-
ble.
■ If “HYBRID S
YSTEM OVERHEAT” is shown on the multi-informa -
tion display
Stop the vehicle in a safe place an d turn of
f the air conditioning
system.
Leave the hybrid system operating and carefully lift the hood.
Remove the engine compartment covers. ( P. 4 2 3 )
Check if the cooling fans are operating.
If the fans are operating: 
Wait until the “HYBRID SYST EM O
VERHEAT” message disap-
pears and then stop the hybrid system. 
If the message does not disappear, call your Lexus dealer.
If the fans are not operating: 
Stop the hybrid system immediately and call your Lexus dealer.

5
When trouble arises
543
5-2. Steps to take in an emergency
After the hybrid system has cooled
down, check the power control
unit coolant level and inspect the
cooling system for leaks.
Add power control unit coolant if
nec
essary.
Water can be used in an emer -
gency if power control unit coolant
is una
vailable. ( P. 5 5 2 )
Have the vehicle inspected at the ne arest Lexus dealer as soon as possi-
ble.
■Overheating
The following symptoms may occur wh en
your vehicle is overheating:
●The high engine coolant temperature warn ing light comes on or flashes, or the
hybrid system output decreases.
●Steam comes out from the engine area.
●“HYBRID SYSTEM OVERHEAT” is displayed on the multi-information display.

544
5-2. Steps to take in an emergency
CAUTION
■To prevent an accident or injury when inspecting under the hood of your vehicle
●If steam is seen coming from under the hood, do not open the hood until the
steam has subsided. The engine compartm ent may be very hot, causing serious
injuries such as burns.
●Check that the indicator on the “POWER ” switch and the READY indicator are
off.
●For vehicles with a hybrid system, there are times when the gasoline engine auto-
matically starts to run or the cooling fans suddenly start to operate. Do not touch
or approach the rotating parts of the belt or fans. Doing so may lead to fingers,
clothes or tools getting caught, resulting in injury.
●Do not loosen the coolant reservoir cap while the hybrid system and radiator are
hot. 
Serious injuries, such as burns, may resu lt from hot coolant and steam released
under pressure.
NOTICE
■When adding engine/power control unit coolant
Wait until the hybrid system has cooled down before adding engine/power control
unit coolant. 
When adding coolant, do so slowly. Adding cool coolant to a hot hybrid system too
quickly can cause damage to the hybrid system.

549
6-1. Specifications
6
Vehicle specifications
This number is also on the Certifi-
cation Label.
■ Engine number and electric motor (tr
action motor) number
The numbers are stamped on the locations shown in the above illustration.
Engine
Model2AZ-FXE
Ty p e4-cylinder in line, 4-cycle, gasoline
Bore and stroke3.48 3.78 in. (88.5  96.0 mm)
Displacement144.1 cu.in. (2362 cm3)
Drive belt tensionAutomatic adjustment
Valve clearance
(engine cold)Intake: 0.007  0.011 in. (0.19  0.29 mm) 
Exhaust: 0.015
 0.019 in. (0.38  0.48 mm)

551
6-1. Specifications
6
Vehicle specifications
■Engine oil selection
“Toyota Genuine Motor Oil” is used in y
our Lexus vehicle. Use Lexus
approved “Toyota Genuine Motor Oil” or equivalent to satisfy the follow-
ing grade and viscosity.
Oil grade: ILSAC multigrade engine oil
Recommended viscosity: SAE 0W-20
SAE 0W-20 is the best choice for
good fuel economy and good
star

ting in cold weather.
If SAE 0W-20 is not available,
S
AE 5W-20 oil may be used.
However, it must be replaced with
SAE 0W-20 at the next oil
change.
The 0W portion of the oil viscosity rating indicates the characteristic of the oil
which allows cold startability. Oils wi th a lower value before the W allow for
easier starting of the engine in cold weather.
The 20 in 0W-20 indicates the oil viscosity when the oil is at its operating
temper
ature. An oil with a higher viscosity may be better suited if the vehicle
is operated at high speeds, or under extreme load conditions.
How to read oil container label:
The ILSAC (International Lubricant St andar
dization and Approval Com-
mittee) Certification Mark is added to some oil containers to help y
ou
select the oil you should use.
Outside temperature