2008 LEXUS RX400H engine coolant

5
When trouble arises
385
5-1. Essential information
RX400h_U
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
● Engine coolant temperature gauge needle continually points
higher than normal
■ 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, sp ongy feeling, pedal almost touches
the floor

424
5-2. Steps to take in an emergency
RX400h_U
If your vehicle overheats
■Electric motor (traction motor) and inverter
If the message WATER TEMP is displayed on the multi-information
display.
■ Gasoline engine
If the needle of the engine coolant temperature gauge enters the
red zone, the gasoline engine has probably overheated.
Observe the following steps:
Stop the vehicle in a safe place and turn off the automatic air
conditioning system.
Check to see if steam is coming out from under the hood.
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 running and carefully lift the hood.
Check to see if the cooling fan is operating.
If the fan is operating: Wait until the temperature of the engine (shown on the
instrument cluste r) begins to fall and then stop the hybrid
system.
If the fan is not operating: Stop the hybrid system immediately and call your local
Lexus dealer.
After the hybrid system has
cooled down sufficiently, check
the engine coolant level and
inspect the radiator core (radia-
tor) for any leaks.
STEP1
STEP2
STEP3
STEP4

5
When trouble arises
425
5-2. Steps to take in an emergency
RX400h_U
■Overheating
If you observe the following, your vehicle may be overheating.
●The message WATER TEMP is displayed on the multi-information display.
●The engine coolant temperature gauge enters the red zone or a loss of power is
experienced.
●Steam is coming from under the hood.
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
injury such as burns.
●Keep hands and clothing away from the fan and other belts while the hybrid sys-
tem is running.
●Do not loosen the radiator cap while the hybrid system and radiator are hot.
Serious injury, such as burns, may result from hot coolant and steam released
under pressure.
Add engine coolant if required.
Water can be used in an emer-
gency measure if engine coolant
is unavailable. (→P. 4 3 5 )
Have the vehicle checked at your nearest Lexus dealer as soon as pos-
sible.
STEP5

426
5-2. Steps to take in an emergency
RX400h_U
NOTICE
■When adding engine coolant
Wait until the engine has cooled down before adding engine coolant.
When adding coolant, do so slowly. Adding cool coolant to a hot engine too quickly
can cause damage to the hybrid system.

435
6-1. Specifications
6
Vehicle specifications
RX400h_U
Cooling system
Ignition system
Capacity
Gasoline engine
power control unit10.9 qt. (10.3 L, 9.0 Imp.qt.)
3.6 qt. (3.4 L, 3.0 Imp.qt.)
Coolant type
Use either of the following.• “Toyota Super Long Life Coolant”
• Similar high-quality ethylene glycol-based non-sili-cate, non-amine, non-nitrite, and non-borate cool-
ant with long-life organic acid technology
Do not use plain water alone.
Spark plug
Make
DENSO
NGK
Gap
SK20R11
IFR6A11
0.043 in. (1.1 mm)
NOTICE
■Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust gap when tuning the gasoline
engine.

451
6-1. Specifications
6
Vehicle specifications
RX400h_U
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 automatic transmis-
sion, 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

474
Alphabetical index
RX400h_U
Do-it-yourself maintenance .............. 310
Door courtesy lightsDoor courtesy lights.........................260
Wattage.................................................... 441
Door lock Back door................................................. 44
Side door .................................................. 39
Wireless remote control................... 36
Door pockets............................................271
Doors Back door................................................. 44
Door glasses ............................................72
Door lock......................................... 36, 39
Power back door ................................. 44
Side door .................................................. 39
Side mirrors ............................................. 68
Driver's seat belt reminder light ...... 391
Driving Break-in tips ........................................... 123
Correct posture .................................... 89
Procedures ............................................. 122
Winter driving tips...............................182
Driving position memory ......................55
DVD player Audio CD/CD text .......................... 248
DVD video ........................................... 239
Initial setting .......................................... 253
MP3 discs ............................................. 249
Video CD.............................................. 246
Electric power steering ....................... 169
Emergency, in case of If the back door opener is in operative................................................ 46
If the hybrid system will not start ................................................ 418 If the shift lever cannot be
shifted from P..................................... 419
If the 12-volt battery is discharged ......................................... 421
If the warning buzzer sounds......388
If the warning light turns on..........388
If you have a flat tire ........................408
If you lose your keys ........................ 420
If you think something is wrong .................................................. 385
If your vehicle becomes stuck ..... 427
If your vehicle needs to be towed ................................................... 378
If your vehicle overheats.................424
Energy monitor ......................................28
Engine
Compartment ....................................... 316
Engine switch .......................................... 131
Hood ......................................................... 313
How to start the hybrid system ...... 131
Identification number ........................ 431
If the hybrid system will not start .................................................418
Ignition switch ......................................... 131
Overheating .........................................424
Engine compartment cover ............... 317
Engine coolant Capacity ................................................ 435
Checking................................................323
Preparing and checking
before winter...................................... 182
Engine coolant temperature
gauge ...................................................... 138
Engine oil
Capacity .................................................434
Checking................................................. 318
E

482
RX400h_U
What to do if...
What to do if...
A tire puncturesP. 4 0 8If you have a flat tire
The hybrid system does not start
P. 4 1 8If the hybrid system will not start
P. 8 3Hybrid vehicle immobilizer system
P. 4 2 1If the 12-volt battery is discharged
The shift lever cannot be
moved outP. 4 1 9If the shift lever cannot be shifted
from P
The engine coolant temperature
gauge enters the red zone
Steam can be seen coming
from under the hood
P. 4 2 4If your vehicle overheats
The key is lostP. 4 2 0If you lose your keys
The 12-volt battery runs outP. 4 2 1If the 12-volt battery is discharged
The doors cannot be lockedP. 3 9Side doors
P. 4 4Back door
The horn begins to soundP. 8 5Alarm
The vehicle is stuck in mud or
sandP. 4 2 7If the vehicle becomes stuck