Lexus HS250h 2010 Hybrid system / LEXUS 2010 HS250H OWNERS MANUAL (OM75006U)

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.

5
When trouble arises
545
5-2. Steps to take in an emergency
If the vehicle becomes stuck
■When changing the shift position
Depress the brake pedal and ensure that t
he vehicle has stopped completely
before changing the shift position. Failure to do so could cause the rejection func -
tion to be activated, canceling the shift position change, or causing the shift position
to change to N automatically.
CAUTION
■When attempting to free a stuck vehicle
If you choose to rock the vehicle back and forth to free it, make sure the surround-
ing area is clear to avoid striking other vehicles, objects or people. The vehicle may
also lunge forward or lunge back sudden ly as it becomes free. Use extreme cau-
tion.
■When shifting the shift lever
Be careful not to shift the shift lever with the accelerator pedal depressed. 
This may lead to unexpected rapid acceleration of the vehicle that may cause an
accident resulting in death or serious injury.
Carry out the following procedures if the tires spin or the vehicle becomes
stuck in mud, dirt or snow:
Apply the parking brak e, change the shift position to P and
stop the hybrid system.
Remove the mud, snow or sand from around the stuck tire.
Place wood, stones or some othe r material under the tir
es to
help provide traction.
Restart the hybrid system.
Make sure to change the shift position to D or R, r
elease the
parking brake, and then care fully depr
ess the accelerator
pedal.
Turn off the TRAC and VSC systems if these functions are hamper -
ing your attempts to free the vehicle. (  P. 2 2 6 )

546
5-2. Steps to take in an emergency
NOTICE
■To avoid damage to the hybrid transmission and other components
●Avoid spinning the wheels and depressing the accelerator pedal more than nec-
essary.
●If the vehicle remains stuck even after these procedures are performed, the vehi-
cle may require towing to be freed.

Vehicle specifications6
547
6-1. SpecificationsMaintenance data 
(fuel, oil level, etc.) .............. 548
Fuel information ..................... 557
Tire information...................... 560
6-2. Customization Customizable features ........ 572
6-3. Initialization Items to initialize .................... 584

548
6-1. Specifications
Maintenance data (fuel, oil level, etc.)
Dimensions and weights
*: Unladen vehicles
Vehicle identification
■Vehicle identification number
The vehicle identification number (VIN ) is the legal identifier for y
our
vehicle. This is the primary identificat ion number for your Lexus. It is used
in registering the ownership of your vehicle.
This number is stamped on the top left of the instrument panel and under the
front passenger’s seat (on some models).
Overall length184.8 in. (4695 mm)
Overall width70.3 in. (1785 mm)
Overall height*59.3 in. (1505 mm)
Wheelbase106.3 in. (2700 mm)
Tr e a dFront60.4 in. (1535 mm)
Rear60.2 in. (1530 mm)
Vehicle capacity weight 
(Occupants + luggage)825 lb. (375 kg)

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)

550
6-1. Specifications
Fuel
Electric motor (Traction motor)
Hybrid battery (Traction battery)
Lubrication system
Fuel typeUnleaded gasoline only
Octane rating87 (Research octane number 91) or higher
Fuel tank capacity14.5 gal. (55 L, 12.5 Imp. gal.)
Ty p ePermanent magnet synchronous motor
Maximum output105 kW
Maximum torque199 ft•lbf (270 N•m, 27.5 kgf•m)
Ty p eNickel-metal hydride battery
Vo l t a g e7.2 V/module
Capacity6.5 Ah (3HR)
Quantity34 modules
Overall voltage244.8 V
Oil capacity 
Drain and refill 
(Reference)
With filter
Without filter

4.5 qt. (4.3 L, 3.8 lmp.qt.)
4.3 qt. (4.1 L, 3.6 lmp.qt.)