engine overheat LEXUS RX400H 2008 Owners Manual

126
2-1. Driving procedures
RX400h_U
CAUTION
■When driving the vehicle
●Use engine braking to maintain a safe speed when driving down a steep hill.
Using the brakes continuously may cause the brakes to overheat and lose effec-
tiveness. (→P. 1 3 5 )
●When stopped on an inclined surface, use the brake pedal and parking brake to
prevent the vehicle from rolling backward or forward and causing an accident.
●Do not adjust the position of the steering wheel, the seat, or the inside or outside
rear view mirrors while driving.
Doing so may result in a loss of vehicle control that can cause accidents that may
result in death or serious injury.
●Always check that all passengers' arms, heads or other parts of their bodies are
not outside the vehicle, as this may result in death or serious injury.
●Do not drive in excess of the speed limit. Even if the legal speed limit permits it, do
not drive over 85 mph (140 km/h) unless your vehicle has high-speed capability
tires. Driving over 85 mph (140 km/h) may result in tire failure, loss of control and
possible injury. Be sure to consult a tire dealer to determine whether the tires on
your vehicle are high-speed capability tires or not before driving at such speeds.
■When driving on slippery road surfaces
●Sudden braking, acceleration and steering may cause tire slippage and reduce
your ability to control the vehicle, resulting in an accident.
●Sudden changes in engine speed, such as engine braking caused by up-shifting
or down-shifting, may cause the vehicle to skid, resulting in an accident.
●After driving through a puddle, lightly depress the brake pedal to make sure that
the brakes are functioning properly. Wet brake pads may prevent the brakes from
functioning properly. If the brakes on only one side are wet and not functioning
properly, steering control may be affected, resulting in an accident.
■When shifting the shift lever
Be careful not to shift the shift lever with the accelerator pedal depressed.
This may lead to unexpected rapid acceleration of the vehicle that may cause an
accident and result in death or serious injury.

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 )

156
2-3. Operating the lights and windshield wipers
RX400h_U
Headlight cleaner switch (if equipped)
■The headlight cleaner can be operated when
When the engine switch must be in the ON position and the headlight switch is
turned ON.
NOTICE
■When the washer fluid tank is empty
Do not use this function when the washer fluid tank is empty.
This may cause the washer fluid pump to overheat.
Washer fluid can be sprayed on the headlights.
Press the switch to clean the
headlights.

170
2-4. Using other driving systems
RX400h_U
When the VSC/traction control are operatingIf the vehicle is in danger of slip-
ping, or if the front wheels (2WD
models) or all wheels (AWD mod-
els) spin, the slip indicator light
flashes to indicate that the VSC/
traction control have been
engaged.
A buzzer (intermittent) sounds to
indicate that VSC is operating.
■Sounds and vibrations caused by the ABS, brake assist, VSC and traction control
●A sound may be heard from the engine compartment when the hybrid system is
started or just after the vehicle begins to move. This sound does not indicate that
a malfunction has occurred in any of these systems.
●Any of the following conditions may occur when the above systems are operat-
ing. None of these indicates that a malfunction has occurred.
• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard after the vehicle comes to a stop.
• The brake pedal may pulsate slightly after the ABS is activated.
• The brake pedal may move down slightly after the ABS is activated.
■Reduced effectiveness of EPS
The effectiveness of EPS is reduced to prevent the system from overheating when
there is frequent steering input over an extended period of time. The steering wheel
may feel heavy as a result. Should this occur, refrain from excessive steering input or
stop the vehicle and turn the hybrid system OFF. The system should return to nor-
mal within 10 minutes.

280
3-6. Other interior features
RX400h_U
Seat heaters (if equipped)
■The seat heaters can be used when
The engine switch is in the ON position.
■When not in use
Turn the knob counterclockwise. The indicator light turns off.
Press the knob into the recessed position.
CAUTION
■Burns
●Use caution when seating the following persons in a seat with the seat heater on
to avoid the possibility of burns:
• Babies, small children, the elderly, the sick and the disabled
• Persons with sensitive skin
• Persons who are fatigued
• Persons who have taken alcohol or drugs that induce sleep (sleeping drugs,cold remedies, etc.)
●Do not cover the seat with anything when using the seat heater.
Using the seat heater with a blanket or cushion increases the temperature of the
seat and may lead to overheating.
Pops the switch out
ON
The indicator light comes on.
Adjusts the seat temperature
The further you turn the knob
clockwise, the warmer the seat
becomes.
Driver’s
seat Front
passenger’s
seat

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

473
Alphabetical index
RX400h_U
CareExterior ................................................... 298
Interior.......................................................301
Seat belts ............................................... 302
Cargo capacity ....................................... 178
Cargo hooks .......................................... 284
CD changer CD .............................................................. 214
MP3 disc ............................................... 220
WMA disc ............................................ 220
CD player.................................................. 214
Chains......................................................... 184
Child restraint system Booster seats, definition.................. 108
Booster seats, installation ..................113
Convertible seats, definition ......... 108
Convertible seats, installation .........113
Front passenger occupant
classification system .......................103
Infant seats, definition ....................... 108
Infant seats, installation........................113
Installing CRS with lower
anchorages ...........................................116
Installing CRS with seat belts ..........113
Installing CRS with top straps ........ 118
Child safety
Air bag precautions ............................ 98
Battery precautions.............. 328, 423
Child restraint system ...................... 108
Child-protectors................................... 40
How your child should wear the seat belt ...........................................62
Installing child restraints ..................... 112
Moon roof precautions ...................... 77
Power window lock switch .............. 72
Power window precautions............. 74 Removed rear seat entertainment
system controller battery............. 351
Removed wireless remote control battery precautions .......................349
Seat belt comfort guide .....................59
Seat belt extender precautions...... 64
Seat belt precautions .......................... 62
Seat heater precautions................. 280
Child-protectors ...................................... 40
Cleaning Exterior................................................... 298
Interior ...................................................... 301
Seat belts ................................................302
Clock ......................................................... 274
Coin holder .............................................268
Compass .................................................. 292
Condenser .............................................. 325
Console box ........................................... 266
Cooling system Engine overheating........................... 424
Cruise control Cruise control........................................157
Dynamic laser cruise control ........ 160
Cup holder .............................................. 269
Curtain shield airbags............................. 91
Customizable features .......................458
Daytime running light system ........... 149
Defogger Rear window ........................................204
Side mirror.............................................204
Dimension................................................430
Dinghy towing ......................................... 196
Display
Dynamic laser cruise control ........ 160
Trip information ................................... 146C
D

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

477
Alphabetical index
RX400h_U
Luggage compartment lightsSwitch ..........................................................46
Wattage ................................................... 441
Luggage cover ...................................... 284
Maintenance
Do-it-yourself maintenance ...........310
General maintenance .....................306
Maintenance data ............................. 430
Maintenance requirements .......... 304
Meter Instrument panel light control ....... 139
Meters .......................................................138
Meter ring light ..................................... 260
Mirrors Inside rear view mirror .......................67
Side mirror heater ............................. 204
Side mirrors............................................. 68
Vanity mirrors ......................................273
Moon roof ...................................................75
MP3 disc ................................................. 220
Multi-display
Brightness control..............................276
Multi-information display
Energy monitor ..................................... 28
Odometer .................................................138
Oil Engine oil .................................................318
Opener
Back door .................................................44
Fuel filler door ........................................ 78
Hood ......................................................... 313
Outside rear view mirrors
Adjusting and folding ......................... 68
Driving position memory ................. 55 Outside temperature display .......... 275
Overhead console ............................... 269
Overhead courtesy lights .................260
Overheating, Engine........................... 424
Parking brake ...........................................137
Parking lights
Replacing light bulbs ....................... 365
Switch........................................................ 148
Wattage ....................................................441
Personal lights Personal lights .................................... 260
Switch.......................................................264
Wattage ....................................................441
Power meter ............................................ 138
Power outlet............................................ 277
Power windows ........................................ 72
Radiator .................................................... 325
Radio .......................................................... 207
RDS ........................................................... 208
Rear audio system ................................ 233
Rear seat entertainment system Audio CD/CD text ..........................248
DVD video ............................................239
Initial setting ..........................................253
MP3 discs.............................................. 249
Rear seat entertainment
system .................................................. 233
Replacing controller battery........ 350
Video ........................................................ 251
Video CD ..............................................246
Rear seats Adjustment ............................................... 52
Folding down .......................................... 52
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