2012 Lexus HS250h Owner's Manual

552
5-2. Steps to take in an emergency
HS250h_U_75050U
If your vehicle overheats
Correction procedures■ If the engine coolant temperature warning light comes on or flashes
Stop the vehicle in a safe place and turn off the air conditioning
system.
Check to see if steam is coming out from the engine area.
If you see steam:
Stop the hybrid system. Carefully lift 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.
Check to see if the cooling fans are operating.
If the fans are operating:
Wait until the high engine coolant temperature warning light goes
off and then stop the hybrid system.
If the fans are not operating:
Stop the hybrid system immediat ely 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 SYSTEM OVERHEAT” is shown on the multi-information
display:
The power control unit may be overheating.
Follow the correction procedure as described below.

5
When trouble arises
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5-2. Steps to take in an emergency
HS250h_U_75050UAfter the hybrid system has cooled
down sufficiently, check the engine
coolant level and inspect the cool-
ing system for leaks.
If the engine compartment cover
needs to be removed. (
→P. 4 3 8 )
Add engine coolant if necessary.
Water can be used in an emer-
gency if engine coolant is unavail-
able. ( →P. 5 6 4 )
Have the vehicle inspected at the nearest Lexus dealer as soon as possi-
ble.
■If “HYBRID SYSTEM OVERHEAT” is shown on the multi-informa-
tion display
Stop the vehicle in a safe place.
Stop the hybrid system (press the “POWER” switch once), and
then carefully lift the hood.
Wait until the hybrid system has
fully cooled down. When the sys-
tem has fully cooled down, check if
coolant has leaked from the radia-
tor core.
If a large amount of coolant leak-
age is found, contact your Lexus
dealer immediately.

554
5-2. Steps to take in an emergency
HS250h_U_75050UCheck that the coolant level of the
power control unit is between the
“FULL” and “LOW” lines of the
reservoir tank.
“FULL” line
“LOW” line
If the coolant level of the power
control unit is insufficient, add
more coolant.
If power control unit coolant is
unavailable, water can be used as
an emergency substitute.
Restart the hybrid system (depress and hold the brake pedal, and
press the “POWER” switch once). Check that the “HYBRID
SYSTEM OVERHEAT” message has gone off.
If the warning message remains on, stop the hybrid system and
contact your Lexus dealer.
Have the vehicle inspected at the nearest Lexus dealer as soon as possi-
ble.
■Overheating
The following symptoms may occur when your vehicle is overheating:
●The high engine coolant temperature warning 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.

5
When trouble arises
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5-2. Steps to take in an emergency
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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 compartment 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 result 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.
■To prevent damage to the cooling system
Observe the following precautions:
●Avoid contaminating the coolant with foreign matter (such as sand or dust etc.)
●Do not use commercially available coolant additives

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5-2. Steps to take in an emergency
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If the vehicle becomes stuck
■When changing the shift position
Depress the brake pedal and ensure that the 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 suddenly 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 brake, 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 other material under the tires to
help provide traction.
Restart the hybrid system.
Make sure to change the shift position to D or R, release the
parking brake, and then carefully depress the accelerator
pedal.
Turn off the TRAC and VSC systems if these functions are hamper-
ing your attempts to free the vehicle. ( → P. 2 3 9 )

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When trouble arises
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5-2. Steps to take in an emergency
HS250h_U_75050U
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.

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5-2. Steps to take in an emergency
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If your vehicle has to be stopped in an emergency
CAUTION
■If the hybrid system has to be turned off while driving
Power assist for the brakes and steering wheel will be lost, making the brake pedal
harder to depress and the steering wheel heavier to turn. Decelerate as much as
possible before turning off the hybrid system.
Only in an emergency, such as if it becomes impossible to stop the vehicle
in the normal way, stop the vehicle using the following procedure:
Steadily step on the brake pedal with both feet and firmly
depress it.
Do not pump the brake pedal repeatedly as this will increase the
effort required to slow the vehicle.
Change the shift position to N.
If the shift position can be changed to N After slowing down, stop the vehicle in a safe place by the road.
Stop the hybrid system.
If the shift position cannot be changed to N Keep depressing the brake pedal with both feet to reduce vehi-
cle speed as much as possible.
Stop the hybrid system by press-
ing and holding the “POWER”
switch for 3 consecutive sec-
onds or more.
Stop the vehicle in a safe place by the road.
Press and hold for 3 seconds or more

Vehicle specifications6
559
HS250h_U_75050U
6-1. SpecificationsMaintenance data (fuel, oil level, etc.) .............. 560
Fuel information ..................... 569
Tire information...................... 572
6-2. Customization Customizable features ........ 584
6-3. Initialization Items to initialize .................... 596