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4-3. Do-it-yourself maintenance
4
Maintenance and care
RX400h_U■
Back-up lights
Open the back door and remove
the luggage compartment light
unit.
Pull out the connector.
Remove the upper trim board.
Remove the lower trim board.
STEP1
STEP2
STEP3
STEP4
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4-3. Do-it-yourself maintenance
RX400h_UTurn the bulb base counterclock-
wise.
Remove the light bulb.
■ License plate lights
Open the back door and remove
the luggage compartment light
unit.
Pull out the connector.
STEP5
STEP6
STEP1
STEP2
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4-3. Do-it-yourself maintenance
4
Maintenance and care
RX400h_URemove the upper trim board.
Turn the bulb base counterclock-
wise.
Remove the light bulb.
■ Bulbs other than the above
If any of the bulbs listed below has burnt out, have your Lexus dealer
replace it.
●Headlight low beams (discharge bulbs)
● Fog lights
● Stop lights
● Tail lights
● High mounted stoplight
STEP3
STEP4
STEP5
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4-3. Do-it-yourself maintenance
RX400h_U
■Condensation build-up on the inside of the lens
Contact your Lexus dealer for more information in the following situations. Tempo-
rary condensation build-up on the inside of the headlight lens does not indicate a
malfunction.
●Large drops of water are built up on the inside of the lens.
●Water has built up inside the headlight.
■Discharge headlights
If voltage to the discharge bulbs is insufficient, the bulbs may not come on, or may
go out temporarily. The discharge bulbs will come on when normal power is
restored.
■LED stop lights
The stop lights, tail lights and high mounted stoplight consist of a number of LEDs. If
any of the LEDs burn out, take your vehicle to your Lexus dealer to have the light
replaced.
If two or more LEDs in a stop light burn out, your vehicle may not conform to local
laws (SAE).
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4-3. Do-it-yourself maintenance
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Maintenance and care
RX400h_U
CAUTION
■Replacing light bulbs
●Turn off the headlights. Do not attempt to replace the bulb immediately after turn-
ing off the headlights.
The bulbs become very hot and may cause burns.
●Do not touch the glass portion of the light bulb with bare hands. Hold the bulb by
the plastic or metal portion.
If the bulb is scratched or dropped it may blow out or crack.
●Fully install light bulbs and any parts used to secure them.
Failing to do so may result in heat damage, fire, or water entering the headlight
unit. This may damage the headlights or cause condensation to build up on the
lens.
●Do not attempt to take apart or repair the low beam discharge headlight bulbs,
connectors, power supply circuits, or related components.
Doing so could result in electric shock and serious injury or death.
■Discharge headlights
●Contact your Lexus dealer before replacing discharge headlights (including light
bulbs).
●Do not touch the high-intensity discharge headlight’s high voltage socket when
the headlights are turned on.
An extremely high voltage of 20000 V will be discharged and could result in
serious injury or death by electric shock.
■To prevent damage or fire
Make sure bulbs are fully seated and locked.
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RX400h_U
5-2. Steps to take in an emergency
If a warning light turns on or a warning buzzer sounds...
Stop the vehicle immediately. Continuing to drive the vehicle may be dangerous.
The following warning indicates a possible problem in the brake system.
Immediately stop the vehicle in a safe place and contact your Lexus
dealer.
*: Parking brake engaged warning buzzer:
→P. 4 0 2
Warning lightWarning light/Details
(U.S.A.)
(Canada)
Brake system warning light (warning buzzer)*
•Low brake fluid
• Malfunction in the electronically controlled brake system
This light also comes on when the parking brake is not
released. If the light turns off after the parking brake is fully
released the system is operating normally.
(U.S.A.)
(Canada)Brake system warning lightIndicates a malfunction in the vehicle’s brake system.
Calmly perform the following actions if any of the warning lights turn on or
flash. If a light turns on or flashes, but then turns off, this does not necessar-
ily indicate a malfunction in the system.
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5-2. Steps to take in an emergency
RX400h_U
If the hybrid system will not start
If the hybrid system will not start, even though correct starting procedures
are being followed (
→P. 131), consider each of the following points.
■The hybrid system will not start even when the starter motor oper-
ates normally.
One of the following may be the cause of the problem.
● There may not be sufficient fuel in the vehicle’s tank.
Refuel your vehicle.
● The hybrid system may be flooded.
Try to restart the hybrid system once more following correct
starting procedures. ( →P. 131)
● There may be a malfunction in the hybrid vehicle immobilizer sys-
tem. (→ P. 8 3 )
■ The interior lights and headlights are dim, or the horn does not
sound or sounds at a low volume.
One of the following may be the cause of the problem.
● The 12-volt battery may be discharged. ( →P. 4 2 1 )
● The 12-volt battery terminal connections may be loose or cor-
roded.
■ The interior lights and headlights do not turn on, or the horn does
not sound.
One of the following may be the cause of the problem.
● One or both of the 12-volt battery terminals may be discon-
nected.
● The 12-volt battery may be discharged. ( →P. 4 2 1 )
Contact your Lexus dealer if the problem cannot be repaired, or if
repair procedures are unknown.
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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