coolant temperature LEXUS RX400H 2008 Owners Manual

138
RX400h_U
2-2. Instrument cluster
Gauges and meters
The units used on the speedometer and the power meter gauge display may
differ depending on the model/type.

The following gauges and meters illuminate when the engine switch is
in the ON position.Power meter
Displays the instantaneous output from the hybrid system in approximate
kilowatts.
Speedometer
Displays the vehicle speed.
Fuel gauge
Displays the quantity of fuel remaining in the tank.
Engine coolant temperature gauge
Displays the engine coolant temperature.
Multi-information display ( →P. 143)
Odometer/trip meter and trip meter reset button
Switches between odometer and trip meter displays. Pushing and holding
the button will reset the trip meter when the trip meter is being displayed.

139
2-2. Instrument cluster
2
When driving
RX400h_U
Instrument panel light controlThe brightness of the instrument panel lights can be adjusted. Darker
Brighter
NOTICE
■To prevent damage to the engine and its components
The engine may be overheating if the engine coolant temperature gauge is in the
red zone (H). In this case, immediately stop the vehicle in a safe place, and check
the engine after it has cooled completely. ( →P. 4 2 4 )

182
2-5. Driving information
RX400h_U
Winter driving tips
Carry out the necessary preparations and inspections before driving the
vehicle in winter. Always drive the vehicle in a manner appropriate to the
prevailing weather conditions.
■Pre-winter preparations
● Use fluids that are appropriate to the prevailing outside tempera-
tures.
• Engine oil
• Engine/power control unit coolant
• Washer fluid
• Have a service technician inspect the level and specific gravity
of battery electrolyte.
● Have the vehicle fitted with four snow tires or purchase a set of
tire chains for the front tires.
Ensure that all tires are the same size and brand, and that chains match
the size of the tires.
●Tire pressure falls in winter as the outside temperature falls. Add
2.9 to 4.3 psi (20 to 30 kPa, 0.2 to 0.3 kgf/cm2 or bar) to the
standard tire inflation pressure.

194
2-5. Driving information
RX400h_U●
Avoid sudden braking as you may sk id, resulting in jackknifing and loss
of control. This is especially true on wet or slippery surfaces.
● Avoid jerky starts or sudden acceleration.
● Avoid jerky steering and sharp turns, and slow down before making
turns.
● Note that when making a turn, the trailer wheels will be closer than the
vehicle wheels to the inside of the turn. Compensate by making a
larger than normal turning radius.
● Crosswinds and rough roads will adversely affect handling of your
vehicle and trailer, causing sway. Periodically check the rear to prepare
for being passed by large trucks or buses, which may cause your vehi-
cle and trailer to sway. If swaying occurs, firmly grip the steering wheel,
reduce speed immediately but gradually, and steer straight ahead.
Never increase speed. If you make no extreme correction with the
steering or brakes, your vehicle and trailer will stabilize.
● Take care when passing other vehicles. Passing requires considerable
distance. After passing a vehicle, do not forget the length of your
trailer, and be sure you have plenty of room before changing lanes.
● Due to the added load of the trailer, your vehicle's hybrid system may
overheat on hot days (at temperatures over 85°F [30°C]) when driv-
ing up a long or steep grade. If the coolant temperature gauge indi-
cates overheating, immediately turn off the air conditioning (if in use),
pull your vehicle off the road and stop in a safe spot. ( →P. 4 2 4 )

312
4-3. Do-it-yourself maintenance
RX400h_U
CAUTION
The engine compartment contains many mechanisms and fluids that may move sud-
denly, become hot, or become electrically energized. To avoid death or serious injury:
■When working on the engine compartment
●Keep hands, clothing, and tools away from the moving fan and engine drive belt.
●Be careful not to touch the engine, inverter, radiator, exhaust manifold, etc. right
after driving as they may be hot. Oil and other fluids may also be hot.
●Do not leave anything that may burn easily, such as paper or rags, in the engine
compartment.
●Do not smoke, cause sparks or expose an open flame to fuel or the battery. Fuel
and battery fumes are flammable.
●Be extremely cautious when working on the battery. It contains poisonous and
corrosive sulfuric acid.
●Never touch, disassemble, remove or replace the high voltage parts, cables and
their connectors. It can cause severe burns or electric shock that may result in
death or serious injury.
●When the hybrid system is operating with the READY light on, the engine may
suddenly start in some cases. When you inspect the engine compartment, be
sure to turn off the hybrid system.
■When working near the electric cooling fan or radiator grille
Be sure the engine switch is off.
With the engine switch on, the electric cooling fan may automatically start to run if
the air conditioning is on and/or the coolant temperature is high. (→P. 3 2 5 )
■Safety glasses
Wear safety glasses to prevent flying or falling material, fluid spray, etc. from getting
in the eyes.
NOTICE
■If you remove the air cleaner:
Driving with the air filter removed may cause excessive engine wear due to dirt in
the air. Also a backfire could cause a fire in the engine compartment.

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

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