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4-3. Do-it-yourself maintenance
4
Maintenance and care
RX400h_U
Washer fluidIf any washer does not work or the
low washer fluid warning light
comes on, the washer tank may be
empty. Add washer fluid.
CAUTION
■Emergency measures regarding electrolyte
●If electrolyte gets on your skin
Wash the affected area thoroughly. If you feel pain or burning, get medical atten-
tion immediately.
●If electrolyte gets on your clothes
It can soak through clothing on to your skin. Immediately take off the clothing and
follow the procedure above if necessary.
●If you accidentally swallow electrolyte
Drink a large quantity of water or milk. Follow with milk of magnesia, beaten raw
egg or vegetable oil. Get emergency medical attention immediately.
■When replacing the 12-volt battery
Use a 12-volt battery designed for the RX400h. Failure to do so may cause gas
(hydrogen) to enter the passenger compartment, causing a fire or explosion.
For replacement of the 12-volt battery, contact your Lexus dealer.
NOTICE
■When recharging the 12-volt battery
Never recharge the 12-volt battery while the hybrid system is running. Also, be sure
all accessories are turned off.
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4-3. Do-it-yourself maintenance
RX400h_U
Wireless remote control battery
Replace the battery with a new one if it is discharged.
■You will need th e following items:
● Small Phillips-head screwdriver
● Lithium battery (CR2016)
■ Replacing the battery
Remove the screw and cover.
Push the cover in the arrow
direction.
Remove the module.
Open the case cover and
remove the depleted battery.
Insert a new battery with the +
terminal facing up.
STEP1
STEP2
STEP3
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4-3. Do-it-yourself maintenance
4
Maintenance and care
RX400h_U
■If the battery is discharged
The following symptoms may occur.
●The wireless remote control will not function properly.
●The operational range is reduced.
■Use a CR2016 lithium battery
●Batteries can be purchased at your Lexus dealer, jewelers, or camera stores.
●Replace only with the same or equivalent type recommended by a Lexus dealer.
●Dispose of used batteries according to the local laws.
CAUTION
■Removed battery and other parts
Keep away from children.
These parts are small and if swallowed by a child they can cause choking.
NOTICE
■For normal operation after replacing the battery
Observe the following precautions to prevent accidents.
●Always work with dry hands.
Moisture may cause the battery to rust.
●Do not touch or move any other components inside the remote control.
●Do not bend either of the battery terminals.
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4-3. Do-it-yourself maintenance
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Maintenance and care
RX400h_U
CAUTION
■Removed battery and other parts
Keep away from children.
These parts are small and if swallowed by a child they can cause choking.
NOTICE
■For normal operation after replacing the battery
Observe the following precautions to prevent accidents.
●Always work with dry hands.
Moisture may cause the battery to rust.
●Do not touch or move any other components inside the remote control.
●Do not bend either of the battery terminals.
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When trouble arises5
377
RX400h_U
5-1. Essential information .... 378If your vehicle needs to be towed ...................................... 378
If you think something is wrong ...................................... 385
Event data recorder.............. 386
5-2. Steps to take in an emergency ................... 388
If a warning light turns on or a warning buzzer
sounds... ................................. 388
If a warning message is displayed................................ 398
If you have a flat tire............... 408
If the hybrid system will not start ................................... 418
If the shift lever cannot be shifted from P ........................ 419
If you lose your keys .............. 420
If the 12-volt battery is discharged ............................. 421
If your vehicle overheats ..... 424
If the vehicle becomes stuck......................................... 427
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When trouble arises
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5-2. Steps to take in an emergency
RX400h_U
Stop the vehicle immediately.The following warnings indicate the possibility of damage to the vehicle
that may lead to an accident. Immediately stop the vehicle in a safe place
and contact your Lexus dealer.
Have the vehicle inspected by yo ur Lexus dealer immediately.
Failing to investigate the cause of the following warnings may lead to the
system operating abnormally and possibly cause an accident. Have the
vehicle inspected by your Lexus dealer immediately.
Warning lightWarning light/Details
Charging system warning light Indicates a malfunction in the vehicle’s charging system.
Warning lightWarning light/Details
(U.S.A.)
(Canada)
Malfunction indicator lampIndicates a malfunction in:
• The electronic engine control system or
• The electronic throttle control system.
Hybrid battery warning lightIndicates a malfunction in the vehicle’s hybrid battery.
SRS warning light
Indicates a malfunction in:
• The SRS airbag system;
• The front passenger occupant classification system; or
• The seat belt pretensioner 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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When trouble arises
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5-2. Steps to take in an emergency
RX400h_U
If the 12-volt battery is discharged
The following procedures may be used to start the hybrid system if the vehi-
cle’s battery is discharged.
You can call your Lexus dealer, or qualified repair shop.
If you have a set of jumper (or booster) cables and a second vehicle
with a 12-volt battery, you can jump start your Lexus following the steps
below.Remove the engine compartment cover.
(→ P. 3 1 7 )
Connecting the jumper cables.
If required, remove all vent plugs from the booster battery. Lay a
cloth over the open vents on the booster battery. (This helps reduce
the explosion hazard, personal injuries and burns.)
Positive (+) battery terminal on your vehicle
Positive (+) battery terminal on the second vehicle
Negative (-) battery terminal on the second vehicle
Connect the jumper cable to ground on your vehicle as shown in the
illustration. Start the hybrid system of the second vehicle. Increase the gas-
oline engine speed slightly and maintain at that level for
approximately 5 minutes to recharge the battery of your vehi-
cle.
Maintain the gasoline engine speed on the second vehicle and
start the vehicle’s hybrid system.
STEP1
STEP2
STEP3
STEP4