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5
When trouble arises
405
5-2. Steps to take in an emergency
RX400h_U
Wa r n i n g m e s s a g eDetailsCorrection procedure
Indicates low tire pres-
sure.Check the tire inflation
pressure, and adjust to the
appropriate level.
(If equipped, flashing
and then continuously on)
(Flashing)Indicates that the radar
cruise control sensor is
dirty or covered with ice.
Clean the sensor.
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407
5-2. Steps to take in an emergency
RX400h_U
Have the malfunction repaired immediately.After taking the specified steps to co rrect the suspected problem, check
that the warning light turns off.
■Changing the engine oil (U.S.A. only)
Make sure to reset the oil change system. ( →P. 3 2 1 )
■Warning light display in radar cruise mode
In the following cases, the warning light may not be displayed even if vehicle-to-
vehicle distance closes.
●When your vehicle and the vehicle ahead are traveling at the same speed or the
vehicle ahead is traveling more quickly than your vehicle
●When the vehicle ahead is traveling at a very low speed
●Immediately after cruise control speed is set
●At the instant the accelerator pedal is depressed
Wa r n i n g m e s s a g eDetailsCorrection
procedure
(Comes on for 8 seconds.)
Indicates that the fuel
door left open after refuel-
ing when start the vehicle/
leave the fuel door open
for more than 30 minutes
during refueling.
Close the fuel lid.
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5-2. Steps to take in an emergency
RX400h_U
CAUTION
■Using the tire jack
Improper use of the tire jack may lead to death or injuries due to the vehicle sud-
denly falling off the jack.
●Do not use the tire jack for any purpose other than replacing tires or installing and
removing tire chains.
●Only use the tire jack that comes with this vehicle for replacing a flat tire.
Do not use it on other vehicles, and do not use other tire jacks for replacing tires
on this vehicle.
●Always check that the tire jack is securely set to the jack point.
●Do not put any part of your body under the vehicle supported by a jack.
●Do not start or run the engine while your vehicle is supported by the jack.
●Do not raise the vehicle while someone is in it.
●When raising the vehicle, do not put an object on or under the jack.
●Do not raise the vehicle to a height greater than that required to replace the tire.
●Use a jack stand if it is necessary to get under the vehicle.
Take particular care when lowering the vehicle to ensure that no one working on or
near the vehicle may be injured.
■Replacing a flat tire
Observe the following precautions to reduce the risk of death or serious injury:
●Never use oil or grease on the wheel bolts or wheel nuts.
The oil or grease can cause the wheel nuts to loosen, causing a serious accident.
Remove any oil or grease on the wheel bolts or wheel nuts.
●Have the wheel nuts tightened with a torque wrench to 76 ft•lbf (103 N•m, 10.5
kgf•m) as soon as possible after changing wheels.
Failure to follow these precautions could cause the nuts to loosen and the wheels
may fall off, which could lead to an accident causing death or serious injury.
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5-2. Steps to take in an emergency
RX400h_U
■Starting the hybrid system when the 12-volt battery is discharged
The hybrid system cannot be started by push-starting.
■Avoiding a discharged battery
●Turn off the headlights and the audio system while the hybrid system is turned off.
●Turn off any unnecessary electrical components when the vehicle is running at a
low speed for an extended period, such as in heavy traffic, etc.
■After recharging the 12-volt battery
(→ P. 3 2 8 )
■When the battery is removed or discharged
The power windows, power back door and moon roof must be initialized.
(→ P. 4 6 2 )
CAUTION
■Avoiding battery fires or explosions
Observe the following precautions to prevent accidentally igniting the flammable
gas that may be emitted from the battery.
●Make sure the jumper cable is connected to the correct terminal and that it is not
unintentionally in contact with any part other than the intended terminal.
●Do not allow the jumper cables to come into contact with the “+” and “-” termi-
nals.
●Do not allow open flame or use matches, cigarette lighters or smoke near the
battery.
Once the vehicle’s hybrid system has started, remove the
jumper cables in the exact reverse order in which they were
connected.
Once the hybrid system starts, have the vehicle checked at your Lexus
dealer as soon as possible.STEP5
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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
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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
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436
6-1. Specifications
RX400h_U
Electrical system
12-volt battery
Open voltage at
68°F (20 °C):12.6 12.8 V Fully charged
12.2
12.4 V Half charged
11.8
12.0 V Discharged
(Voltage checked 20 minutes after the
key is removed from the engine switch
with all the lights turned off)
Charging rates5 A max.
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RX400h_U
Alphabetical index
Alphabetical index
A/C ............................................................. 198
ABS.............................................................. 169
Adaptive front lighting system ......... 149
AFS .............................................................. 149
Air conditioning filter ..........................346
Air conditioning systemAir conditioning filter ....................... 346
Automatic air conditioning system ................................................... 198
Air bags
Air bag operating conditions ......... 93
Air bag precautions for your child.......................................................... 98
Air bag warning light .......................389
Curtain shield airbag operating conditions.............................................. 94
Curtain shield airbag precautions .......................................... 98
Front passenger occupant classification system....................... 103
General airbag precautions ........... 98
Locations of airbags.............................. 91
Modification and disposal of airbags ...................................................102
Proper driving posture .............89, 98
Side airbag operating conditions.............................................. 94
Side airbag precautions .................... 98
SRS airbags ............................................... 91
Alarm ............................................................85
Antenna ....................................................... 211
Anti-lock brake system ....................... 169
Armrest .....................................................282
Audio system
Antenna ......................................................211 Audio visual input................................ 251
A/V input adapter .............................. 251
CD player/changer ........................... 214
MP3/WMA disc............................... 220
Optimal use ......................................... 228
Radio ........................................................207
Steering wheel audio switch.......... 231
Audio visual input ...................................251
Automatic air conditioning system ..................................................... 198
Automatic headlight leveling system ..................................................... 150
Automatic light control system........ 148
A/V input adapter..................................251
Back door Back door ................................................. 44
Wireless remote control ...................36
Back-up lights Replacing light bulbs ....................... 365
Wattage ................................................... 441
Battery
Checking................................................327
If the 12-volt battery is discharged ......................................... 421
Preparing and checking
before winter...................................... 182
Brake
Fluid.......................................................... 325
Parking brake........................................ 137
Brake assist ...............................................169
Break-in tips..............................................123
Brightness control Multi-display light control .............. 276A
B