engine coolant Lexus HS250h 2010 User Guide

5
When trouble arises
489
5-1. Essential information
HS250h_U_75033U(Canada)
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably needs
adjustment or repair. Contact your Lexus dealer as soon as possible.
■Visible symptoms
● Fluid leaks under the vehicle
(Water dripping from the air conditioning after use is normal.)
● Flat-looking tires or uneven tire wear
● High engine coolant temperature warning light flashes or comes
on
■ Audible symptoms
● Changes in exhaust sound
● Excessive tire squeal when cornering
● Strange noises related to the suspension system
● Pinging or other noises related to the hybrid system
■ Operational symptoms
● Engine missing, stumbling or running rough
● Appreciable loss of power
● Vehicle pulls heavily to one side when braking
● Vehicle pulls heavily to one side when driving on a level road.
● Loss of brake effectiveness, spongy feeling, pedal almost touches
the floor

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When trouble arises
493
5-2. Steps to take in an emergency
HS250h_U_75033U(Canada)
Have the vehicle inspected by your Lexus dealer immediately.Failing to investigate the cause of the following warnings may lead to the
system operating abnormally and possibly cause an accident. Have the
vehicle inspected by your Lexus dealer immediately.
High engine coolant temperatur e warning light (flashes or
comes on)
Indicates that the engine is overheating →P. 5 4 1
• Flashes: Engine is overheating. Drive carefully.
• Comes on: Engine is overheated. Stop the vehicle.
Warning lightWarning light/Details
Brake system warning light (yellow indicator) Indicates a malfunction in:
• The regenerative brake system; or
• The electronically controlled brake system
(U.S.A.)

(Canada)
Malfunction indicator lampIndicates a malfunction in:
• The hybrid system;
• The electronic engine control system;
• The electronic throttle control system; or
• The hybrid transmission control system
SRS warning light
Indicates a malfunction in:
• The SRS airbag system;
• The front passenger occupant classification system; or
• The seat belt pretensioner system
(U.S.A.)

(Canada)
“ABS” warning lightIndicates a malfunction in:
•The ABS; or
• The brake assist system
Warning lightWarning light/Details

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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.

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When trouble arises
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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.

568
6-1. Specifications
HS250h_U_75033U(Canada)
Warning: The temperature grades of a tire assume that it is properly inflated
and not overloaded.
Excessive speed, underinflation, or excessive loading, either separately or in
combination, can cause heat buildup and possible tire failure.
Glossary of tire terminology
Tire related termMeaning
Cold tire inflation pres-
sureTire pressure when the vehicle has been parked for
three hours or more, or has not been driven more
than 1 mile or 1.5 km under that condition
Maximum inflation pres-
sureThe maximum cold inflated pressure to which a tire
may be inflated, shown on the sidewall of the tire
Recommended inflation
pressureCold tire inflation pressure recommended by a man-
ufacturer
Accessory weight
The combined weight (in excess of those standard
items which may be replaced) of transmission, power
steering, power brakes, power windows, power seats,
radio and heater, to the extent that these items are
available as factory-installed equipment (whether
installed or not)
Curb weight
The weight of a motor vehicle with standard equip-
ment, including the maximum capacity of fuel, oil and
coolant, and if so equipped, air conditioning and
additional weight optional engine
Maximum loaded vehicle
weight
The sum of:
(a) Curb weight
(b) Accessory weight
(c) Vehicle capacity weight
(d) Production options weight
Normal occupant weight150 lb. (68 kg) times the number of occupants speci-
fied in the second column of Table 1
* that follows

597
Alphabetical index
HS250h_U_75033U(Canada)
If your vehicle has to be stopped in an emergency............................. 547
If your vehicle needs to be towed ................................................... 483
If your vehicle overheats.................. 541
Emergency flasher
Switch ...................................................... 482
Engine
Accessory mode ................................. 146
Compartment ......................................422
Engine switch ........................................ 145
Hood ......................................................... 419
How to start the engine.................... 145
How to start the hybrid system.................................................... 145
Identification number.......................550
If the engine will not start ...............530
If the hybrid system will not
start........................................................530
Ignition switch........................................ 145
Overheating........................................... 541
Power switch ......................................... 145
Engine compartment cover..............423
Engine coolant Capacity................................................. 554
Checking ............................................... 428
Preparing and checking before winter.....................................244
Engine/power control unit coolant Capacity................................................. 554
Checking ............................................... 428
Preparing and checking
before winter.....................................244
Engine immobilizer system ..................96 Engine oil
Capacity .................................................552
Checking ............................................... 424
Preparing and checking
before winter .................................... 244
Engine oil maintenance data............ 426
Engine switch .......................................... 145
Enhanced VSC...................................... 225
EPS ............................................................. 225
EV drive mode switch.......................... 150
Event data recorder ............................490
Floor mat ................................................. 380
Fluid
Brake ....................................................... 556
Washer ................................................... 432
Fog lights Replacing light bulbs ....................... 469
Switch........................................................ 194
Wattage................................................. 558
Foot light...................................................360
Foot well lighting ...................................360
Front fog lights Replacing light bulbs ....................... 469
Switch........................................................ 194
Wattage................................................. 558
Front passenger occupant classification system ............................ 116
Front passenger's seat belt reminder light......................................495
Front seats Adjustment ............................................... 64
Driver’s seat position memory .......68
F
*: Refer to “Navigation System Owner’s Manual”.

603
Alphabetical index
HS250h_U_75033U(Canada)
Snow tires...............................................244
Spare tire ................................................. 521
Tire pressure warning system...................................... 437, 495
Tools ............................................................ 521
Total load capacity................................243
Towing Dinghy towing..................................... 248
Emergency towing ........................... 483
Trailer towing........................................247
TRAC .........................................................225
Traction control .....................................225
Trailer towing .......................................... 247
Trip meter.................................................. 162
Trunk Opener...................................................... 60
Turn signal lights Replacing light bulbs ....................... 469
Switch ........................................................159
Wattage .................................................558
Vanity lights Vanity lights ...........................................372
Wattage .................................................558
Vanity mirrors.........................................372
Vehicle identification number ........ 550
Vehicle stability control ......................225
Ventilators................................................375
VIEW switch*
VSC ............................................................225
Warning buzzers Brake system ....................................... 492
Open door .......................................... 495
Seat belt reminder ............................ 495 Warning lights
AFS OFF ................................................493
Anti-lock brake system ...................493
Brake assist system ...........................493
Brake system........................................492
Charging system................................ 492
Cruise control......................................493
Electric power steering
warning light .....................................493
Electronic engine control
system ..................................................493
High coolant temperature............. 492
Hybrid battery system .....................493
LKA ...........................................................493
Low fuel level ...................................... 495
Low tire pressure .............................. 495
Malfunction indicator lamp ...........493
Master warning light........................ 495
Open door ........................................... 495
Pre-collision system..........................493
Pretensioner .........................................493
Radar cruise co ntrol .........................493
Seat belt reminder light.................. 495
Slip indicator .........................................493
SRS airbags...........................................493
Tire pressure warning light .......... 495
Warning messages Cruise control..................................... 502
Dynamic radar cruise control .....................................502, 505
Electric power steering system ................................................. 502
Engine oil maintenance ................. 505
Engine oil pressure ............................ 501
EV drive mode................................... 505
V
W
*: Refer to “Navigation System Owner’s Manual”.