engine coolant 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.

306
4-2. Maintenance
RX400h_U
General maintenance
Engine compartment
ItemsCheck points
12-volt batteryMaintenance-free. (→P. 3 2 7 )
Brake fluidAt the correct level? ( →P. 3 2 5 )
Engine/power control unit coolantAt the correct level? ( →P. 3 2 3 )
Engine oilAt the correct level? ( →P. 3 1 8 )
Exhaust systemNo fumes or strange sounds?
Radiator/condenser/hosesNot blocked with foreign matter?
(→ P. 3 2 5 )
Wa s h e r f l u i dAt the correct level? ( →P. 3 2 9 )
Listed below are the general maintenance items that should be performed
at the intervals specified in the “Warranty and Services Guide” or
“Owner’s Manual Supplement”. It is recommended that any problem you
notice should be brought to the attent ion of your Lexus dealer or qualified
service shop for advice.

310
RX400h_U
4-3. Do-it-yourself maintenance
Do-it-yourself service precautions
If you perform maintenance yourself, be sure to follow the correct proce-
dure given in these sections.
ItemsParts and tools
12-volt battery condition ( →P. 3 2 7)
•Grease
•Conventional wrench
(for terminal clamp bolts)
Brake fluid level (→ P. 3 2 5 )
Engine/power control unit coolant
level (→ P. 3 2 3 )
• “Toyota Super Long Life Coolant”
or similar high quality ethylene gly-
col based non-silicate, non-amine,
non-nitrite and non-borate coolant
with long-life hybrid organic acid
technology.
For the U.S.A.:
“Toyota Super Long Life Coolant”
is pre-mixed with 50% coolant and
50% deionized water.
For Canada:
“Toyota Super Long Life Coolant”
is pre-mixed with 55% coolant and
45% deionized water.
• Funnel (used only for adding cool- ant)

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.

316
4-3. Do-it-yourself maintenance
RX400h_U
Engine compartment
Brake fluid reservoir(→P. 325)
Engine oil level dipstick (→P. 318)
Engine oil filler cap (→P. 318)
Power control unit coolant
reservoir ( →P. 323)
Fuse boxes ( →P. 352)Engine coolant radiator
(→P. 325)
Condenser ( →P. 325)
Power control unit coolant
radiator ( →P. 325)
Electric cooling fans
Engine coolant reservoir (→P. 323)
12-volt battery ( →P. 327)
Washer fluid tank (→P. 329)

323
4-3. Do-it-yourself maintenance
4
Maintenance and care
RX400h_U
CoolantThe coolant level is satisfactory if it is between the FULL and LOW lines
on the reservoir when the hybrid system is cold. Engine coolant reservoir Reser voir cap
Full (upper line)
Low (lower line)
If the level is on or below the LOW
line, add coolant up to the FULL
line.
Power control unit coolant reservoir

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