Page 594 of 792

594 7-3. Do-it-yourself maintenance
RX450h_RX450hL _U_OM48F85U* : Vehicles with sing le-beam headlightsWasher fluid
( → P. 604) • Water or washer fluid containing antifreeze (for winter use)
• Funnel (used only for adding water or washer fluid)
WARNING
The engine compartment contains many mechan isms and fluids that may move suddenly,
become hot, or become electrically energize d. To avoid death or serious injury, observe
the following precautions. ■
When working on the engine compartment ●
Make sure that the “ACCESSORY” or “I GNITION ON” on the multi-information
display and the “READY” indicator are both off. ●
Keep hands, clothing and tools away from the moving fan and engine drive belt.●
Be careful not to touch the engine, power co ntrol unit, 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 and rags, in the engine
compartment. ●
Do not smoke, cause sparks or expose an open flame to fuel. Fuel fumes are flamma-
ble. ■
When working near the electric cooling fans or radiator grille
Be sure the power switch is off.
With the power switch in ON mode, the electric cooling fans may automatically start to
run if the air conditioning is on and/ or the coolant temperature is high. ( → P. 602)■
Safety glasses
Wear safety glasses to prevent flying or falling material, flui d spray, etc. from getting in
your eyes.
NOTICE ■
If you remove the air cleaner filter
Driving with the air cleaner f ilter removed may cause excessive engine wear due to dirt
in the air. Items Parts and tools
Page 595 of 792
5957-3. Do-it-yourself maintenance
7
Maintenance and care
RX450h_RX450hL _U_OM48F85UPull the hood lock release lever. The hood will pop up slightly.
Pull up the auxiliary catch lever and
lift the hood.Hood Release the lock from the inside of the vehicle to open the hood.1
2
WARNING ■
Pre-driving check
Check that the hood is fully closed and locked.
If the hood is not locked properly, it may op en while the vehicle is in motion and cause
an accident, which may result in death or serious injury.
Page 600 of 792

600 7-3. Do-it-yourself maintenance
RX450h_RX450hL _U_OM48F85U■
After changing the engine oil
The engine oil maintenance data should be reset. Perform the following procedures:
Select on the multi-information display. ( → P. 108)
Press or of the meter control switch, select the “Vehicle Settings” then “Oil
Maintenance”. (To conf irm setting, press .)
Select the “Yes” and push .
A message is displayed on th e multi-information display.
WARNING ■
Used engine oil ●
Used engine oil contains potentially harm ful contaminants which may cause skin dis-
orders such as inflammation and skin cance r, so care should be taken to avoid pro-
longed and repeated contact. To remove used engine oil from your skin, wash
thoroughly with soap and water. ●
Dispose of used oil and filters only in a sa fe and acceptable manner. Do not dispose of
used oil and filters in household trash, in sewers or onto the ground. Call your Lexus
dealer, service station or auto parts store for information concerning recycling or dis-
posal. ●
Do not leave used engine oil within the reac h of children.
NOTICE ■
To prevent serious engine damage
Check the oil level on a regular basis. ■
When replacing the engine oil ●
Be careful not to spill engine oil on the vehicle components.●
Avoid overfilling, or the engine could be damaged. ●
Check the oil level on the dipstick every time you refill the vehicle.●
Be sure the engine oil fille r cap is properly tightened. 1
2
3
4
Page 602 of 792

602 7-3. Do-it-yourself maintenance
RX450h_RX450hL _U_OM48F85UCheck the radiator and condenser an d clear away any foreign objects.
If either of the above parts is extremely dirty or you are not sure of their condi-
tion, have your vehicle inspected by your Lexus dealer. WARNING ■
When the hybrid system is hot
Do not remove the engine/power control unit coolant reservoir caps and radiator cap.
The cooling system may be under pressure and may spray hot coolant if the cap is
removed, causing serious injuries, such as burns.
NOTICE ■
When adding coolant
Coolant is neither plain water nor straight antifreeze. The correct mixture of water and
antifreeze must be used to provide proper lubrication, corrosion protection and cool-
ing. Be sure to read the antifreeze or coolant label.■
If you spill coolant
Be sure to wash it off with water to prevent it from damaging parts or paint.
Radiator and condenser WARNING ■
When the hybrid system is hot
Do not touch the radiator or condenser as they may be hot and cause serious injuries,
such as burns.
Page 603 of 792

6037-3. Do-it-yourself maintenance
7
Maintenance and care
RX450h_RX450hL _U_OM48F85U■
Checking fluid level
The brake fluid level should be
between the “MAX” and “MIN” lines
on the tank.
■
Adding fluid
Make sure to check the fluid type and prepare the necessary item. ■
Brake fluid can absorb moisture from the air
Excess moisture in the brake fluid can cause a dangerous loss of braking efficiency. Use
only newly opened brake fluid.Brake fluid
Fluid type FMVSS No.116 DOT 3 or SAE J1703 brake fluid
Items Clean funnel
WARNING ■
When filling the reservoir
Take care as brake fluid can harm your hands and eyes and damage painted surfaces.
If fluid gets on your hands or in your ey es, flush the affected area with clean water
immediately.
If you still experience di scomfort, see a doctor.
NOTICE ■
If the fluid level is low or high
It is normal for the brake fluid level to go down slightly as the brake pads wear out or
when the fluid level in the accumulator is high.
If the reservoir needs frequent ref illing, there may be a serious problem.
Page 604 of 792
604 7-3. Do-it-yourself maintenance
RX450h_RX450hL _U_OM48F85UIf none of the washer do not work or the
“Windshield Washer Fluid Low”
appears on the multi-information dis-
play, the washer tank may be empty.
Add washer fluid.Washer fluid
WARNING ■
When adding washer fluid
Do not add washer fluid when the hybrid system is hot or operating as washer fluid
contains alcohol and may catch fire if spilled on the engine, etc.
NOTICE ■
Do not use any fluid other than washer fluid
Do not use soapy water or engine antifreeze instead of washer fluid.
Doing so may cause streaking on the vehicle's painted surfaces, as well as damaging
the pump leading to problems of the washer fluid not spraying.■
Diluting washer fluid
Dilute washer fluid with water as necessary.
Refer to the freezing temperatures listed on the label of the washer fluid bottle.
Page 609 of 792

6097-3. Do-it-yourself maintenance
7
Maintenance and care
RX450h_RX450hL _U_OM48F85U■
Before recharging
When recharging, the 12-volt battery produc es hydrogen gas which is flammable and
explosive. Therefore, observe the following precautions before recharging: ●
If recharging with the 12-volt battery installed on the vehicle, be sure to disconnect the
ground cable. ●
Make sure the power switch on the charge r is off when connecting and disconnecting
the charger cables to the 12-volt battery. ■
After recharging/reconnecting the 12-volt battery ●
The hybrid system may not start. Follow the procedure below to initialize the system.
Shift the shift lever to P.
Open and close any of the doors.
Restart the hybrid system. ●
Unlocking the doors using the smart access system with push-button start may not be
possible immediately after reconnecting the 12-volt battery. If this happens, use the
wireless remote control or the mechan ical key to lock/unlock the doors.●
Start the hybrid system with the power sw itch in ACCESSORY mo de. The hybrid sys-
tem may not start with the power switch turned off. However, the hybrid system will
operate normally from the second attempt.●
The power switch mode is recorded by the vehicle. If the 12-volt battery is reconnected,
the vehicle will return the power switch mode to the status it was in before the 12-volt
battery was disconnected. Make sure to turn off the power before disconnect the 12-
volt battery. Take extra care when connec ting the 12-volt battery if the power switch
mode prior to discharge is unknown.
If the system will not start even after multip le attempts at all methods above, contact your
Lexus dealer.
WARNING ■
Chemicals in the 12-volt battery
The 12-volt battery contains poisonous and corrosive sulfuric acid and may produce
hydrogen gas which is flammable and explosive. To reduce the risk of death or serious
injury, take the following precautions while working on or near the 12-volt battery:●
Do not cause sparks by touching the 12-volt battery terminals with tools. ●
Do not smoke or light a matc h near the 12-volt battery.●
Avoid contact with eyes, skin and clothes. ●
Never inhale or swallow electrolyte. ●
Wear protective safety glasses when working near the 12-volt battery. ●
Keep children away from the 12-volt battery. ■
Where to safely charge the 12-volt battery
Always charge the 12-volt battery in an open area. Do not charge the 12-volt battery in
a garage or closed room where th ere is insufficient ventilation.■
How to recharge the 12-volt battery
Only perform a slow charge (5 A or less). The 12-volt battery may explode if charged
at a quicker rate. 1
2
3
Page 610 of 792

610 7-3. Do-it-yourself maintenance
RX450h_RX450hL _U_OM48F85UWARNING ■
Emergency measures regarding electrolyte ●
If electrolyte gets in your eyes
Flush your eyes with clean water for at least 15 minutes and get immediate medical
attention. If possible, continue to apply water with a sponge or cloth while traveling to
the nearest medical facility. ●
If electrolyte gets on your skin
Wash the affected area thoroughly. If you fe el pain or burning, get medical attention
immediately. ●
If electrolyte gets on your clothes
It can soak through clothing on to your s kin. Immediately take off the clothing and fol-
low the procedure above if necessary. ●
If you accidentally swallow electrolyte
Drink a large quantity of water or milk. Get emergenc y medical attention immedi-
ately. ■
When handling the 12-volt battery
→ P. 700 ■
When disconnecting the 12-volt battery (RX450h)
NOTICE ■
When recharging the 12-volt battery
Never recharge the 12-volt battery while the hybrid system is operating. Also, be sure
all accessories are turned off.Do not disconnect the negative (-) terminal on
the body side as shown. The disconnected neg-
ative (-) terminal may touch the positive (+) ter-
minal, which may cause a short and result in
death or serious injury.