cooling Lexus HS250h 2010 User Guide

540
5-2. Steps to take in an emergency
HS250h_U_75033U(Canada)
NOTICE
■Exclusive jump starting terminal precaution
The exclusive jump starting terminal is to be used when charging the 12-volt battery
from another vehicle in an emergency. It cannot be used to jump start another vehi-
cle.
■When handling jumper cables
When connecting the jumper cables, ensure that they do not become entangled in
the cooling fans or belt.

5
When trouble arises
541
5-2. Steps to take in an emergency
HS250h_U_75033U(Canada)
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.
Remove the engine compartment cover. ( →P. 423)
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 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 SYSTEM OVERHEAT” is shown 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
HS250h_U_75033U(Canada)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 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 and turn off the air conditioning
system.
Leave the hybrid system operating and carefully lift the hood.
Remove the engine compartment covers. ( →P. 423)
Check if the cooling fans are operating.
If the fans are operating:
Wait until the “HYBRID SYSTEM OVERHEAT” 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 immediat ely and call your Lexus dealer.

5
When trouble arises
543
5-2. Steps to take in an emergency
HS250h_U_75033U(Canada)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
necessary.
Water can be used in an emer-
gency if power control unit coolant
is unavailable. (
→P. 5 5 4 )
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.

544
5-2. Steps to take in an emergency
HS250h_U_75033U(Canada)
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.

554
6-1. Specifications
HS250h_U_75033U(Canada)
Cooling system
Ignition system
Capacity
Gasoline engine
Po w e r c o n t ro l u n i t
7.7 qt. (7.3 L, 6.4 Imp. qt.)
3.1 qt. (2.9 L, 2.6 Imp. qt.)
Coolant type
Use either of the following.
• “Toyota Super Long Life Coolant”
• A similar high-quality ethylene glycol-based non-silicate, non-amine, non-nitrite,
and non-borate coolant with long-life
hybrid organic acid technology
Do not use plain water alone.
Spark plug
Make
GapDENSO SK20R11
NGK IFR6A11
0.043 in. (1.1 mm)
NOTICE
■Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust spark plug gap.

596
Alphabetical index
HS250h_U_75033U(Canada)
Clock (vehicles withoutnavigation system) ............................ 373
Clock (vehicles with navigation system)*
Coin holder .............................................366
Compass ................................................... 391
Condenser ..............................................430
Console box ...........................................365
Cooling system Engine overheating ............................541
Cruise control Cruise control .......................................201
Dynamic radar cruise control .....205
Cup holders ............................................ 367
Curtain shield airbags.......................... 104
Customizable features ....................... 574
Daytime running light system ........... 186
Defogger Rear window........................................260
Side mirrors ..........................................260
Dimensions............................................. 550
Dinghy towing ........................................248
Display
Dynamic radar cruise control..................................................205
Multi-information display.................169
Trip information .................................... 172
Warning message.............................. 501
Do-it-yourself maintenance .............. 416
Door courtesy lights Door courtesy lights.........................360
Wattage................................................. 558
Doors
Door glasses ........................................... 86
Door lock.................................44, 54, 57 Rear door child protector................ 58
Side doors................................................. 57
Side mirrors............................................. 83
Driver’s seat belt reminder light ..... 495
Driver’s seat position memory ........... 68
Driving
Break-in tips........................................... 137
Correct posture................................... 102
Procedures............................................. 136
Winter driving tips .............................244
Driving position memory...................... 68
Electric power steering...................... 225
Electronic key If the electronic key does not operate properly............................ 533
Emergency, in case of If the electronic key does not
operate properly............................ 533
If the engine will not start ............... 530
If the hybrid system will not start ....................................................... 530
If the 12-volt battery is discharged ........................................ 536
If the warning buzzer sounds.......492
If the warning light turns on...........492
If the warning message is displayed ..............................................501
If you have a flat tire .......................... 521
If you lose your keys ........................ 532
If you think something is wrong .................................................. 489
If your electronic key does not operate properly ................... 533
If your vehicle becomes stuck .... 545
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