cooling Lexus HS250h 2012 User Guide

472
4-3. Do-it-yourself maintenance
HS250h_U_75050U
Fuse layout and amperage ratingsEngine compartment
FuseAmpereCircuit
1HTR50 AAir conditioning system
2RDI40 AElectric cooling fans
3OIL PMP10 AHybrid system, transmission
4S-HORN10 ANo circuit
5ABS MAIN NO.27. 5 AElectronically controlled brake system
6H-LP CLN30 AHeadlight cleaner
7P- CO N M T R30 A
P position control system, hybrid sys-
tem, smart access system with push-
button start
8AMP NO.130 AAudio system, back door opener
9IGCT30 APCU, IGCT NO.2, IGCT NO.3,
hybrid system

475
4-3. Do-it-yourself maintenance
4
Maintenance and care
HS250h_U_75050U
36SPARE30 ASpare fuse
37SPARE10 ASpare fuse
38SPARE7. 5 ASpare fuse
39EFI MAIN20 AEFI NO.2, fuel system
40BATT FAN10 ABattery cooling fan
41IG220 A
Hybrid system, multiport fuel injec-
tion system/sequential multiport fuel
injection system, MET, IGN
FuseAmpereCircuit

5
When trouble arises
551
5-2. Steps to take in an emergency
HS250h_U_75050U
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.

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
555
5-2. Steps to take in an emergency
HS250h_U_75050U
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

564
6-1. Specifications
HS250h_U_75050U
Oil viscosity (0W-20 is explained here as an example):
●The 0W in 0W-20 indicates the characteristic of the oil which allows cold
startability. Oils with a lower value before the W allow for easier starting of
the engine in cold weather.
● The 20 in 0W-20 indicates the viscosity characteristic of the oil when the
oil is at high temperature. An oil with a higher viscosity (one with a higher
value) 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 Standardization and Approval Com-
mittee) Certification Mark is added to some oil containers to help you
select the oil you should use.
Cooling 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.

591
6-2. Customization
6
Vehicle specifications
HS250h_U_75050U
Automatic
air condi-
tioning sys-
tem
(→ P. 2 6 6 )A/C Auto switch
operationAutoManualO——O
Tu r n i n g o n t h e
windshield
defogger acti-
vates the A/C
OnOff———O
Eco drive
mode
(
→P. 1 6 2 )
Heating/cooling
operation mini-
mized in Eco
drive mode
OnOff———O
Front seats
(
→P. 6 8 )
Driver’s seat
movement when
exiting the vehi-
cle (on some
models)
Pa r t i a l
Off
O—OO
Full
Eco Driving
Indicator
Light
(
→P. 1 7 7 )
Activating Eco
Driving Indica-
tor Light
OnOff—OOO
Po w e r w i n -
dows
(
→P. 9 0 )
Mechanical key
linked operationOffOn———O
Wireless remote
control linked
operation
Off
On
(Open only)
———O
Buzzer sounds if
operated using
wireless remote
OnOff———O
ItemFunctionDefault settingCustom-
ized
setting

616
Alphabetical index
HS250h_U_75050U
Cooling systemEngine overheating .......................... 552
Cruise control Cruise control ....................................... 212
Dynamic radar crui se control ....... 216
Cup holders ............................................. 381
Curtain shield airbags.......................... 109
Customizable features ...................... 584
Daytime running light system ........... 194
Defogger* Rear window.........................................274
Side mirrors ...........................................274
Dimensions............................................. 560
Dinghy towing ........................................ 262
Display
Dynamic radar cruise control.................................................... 216
Multi-information display................. 177
Trip information ................................... 180
Warning message............................... 512
Do-it-yourself maintenance .............. 431
Door courtesy lights Door courtesy lights......................... 374
Wattage................................................. 568
Doors
Door glasses ........................................... 90
Door lock.................................. 47, 58, 61
Rear door child protector ................ 62
Side doors .................................................. 61
Side mirrors ............................................. 87
Driver’s seat belt reminder light .... 505
Driver’s seat position memory ........... 72
Driving
Break-in tips ........................................... 143
Correct posture ................................... 107 Procedures............................................. 142
Winter driving tips ............................ 258
Driving position memory.......................72
Electric power steering...................... 238
Electronic key If the electronic key does not operate properly............................ 544
Emergency, in case of If the electronic key does not
operate properly............................ 544
If the engine will not start ................. 541
If the hybrid system will not start ......................................................... 541
If the 12-volt battery is discharged .........................................547
If the warning buzzer sounds...... 502
If the warning light turns on.......... 502
If the warning message is displayed .............................................. 512
If you have a flat tire ........................ 532
If you lose your keys ........................ 543
If you think something is wrong ....................................................501
If your electronic key does not operate properly ................... 544
If your vehicle becomes stuck .... 556
If your vehicle has to be stopped in an emergency ............................558
If your vehicle needs to be
towed ................................................... 495
If your vehicle overheats................ 552
Emergency flasher Switch ...................................................... 494
Engine Accessory mode ................................. 153
D
E