maintenance LEXUS RX450h 2018 Owner's Guide

5977-3. Do-it-yourself maintenance
7
Maintenance and care
RX450h_RX450hL _U_OM48F85U■
12-volt battery
→ P. 605Engine compartment
Washer fluid tank ( → P. 604)
Brake fluid reservoir ( → P. 603)
Engine oil level dipstick
( → P. 598)
Engine coolant reservoir
( → P. 601)
Power control unit coolant reservoir
( → P. 601) Fuse boxes ( → P. 632)
Radiator ( → P. 602)
Power control unit coolant
radiator ( → P. 602)
Condenser ( → P. 602)
Electric cooling fans
Engine oil filler cap ( → P. 599)1
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5 6
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598 7-3. Do-it-yourself maintenance
RX450h_RX450hL _U_OM48F85UWith the engine at operating temperatur e and turned off, check the oil level on
the dipstick. ■
Checking the engine oil
Park the vehicle on level ground. Afte r warming up the engine and turning
off the hybrid system, wait more than 5 minutes for the oil to drain back into
the bottom of the engine.
Holding a rag under the end, pull
the dipstick out.
Wipe the dipstick clean.
Reinsert the dipstick fully.
Holding a rag under the end, pull
the dipstick out and check the oil
level.
Low
Normal
Excessive
The shape of the dipstick may dif-
fer depending on the type of vehi-
cle or engine.
Wipe the dipstick and reinsert it fully.Engine oil 1
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5
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6

5997-3. Do-it-yourself maintenance
7
Maintenance and care
RX450h_RX450hL _U_OM48F85U■
Adding engine oil
If the oil level is below or near the
low level mark, add engine oil of the
same type as that already in the
engine.
Make sure to check the oil type and prepare the items needed before adding
oil.
Remove the oil filler cap by turning it counterclockwise.
Add engine oil slowly, checking the dipstick.
Install the oil filler cap by turning it clockwise.■
Engine oil consumption
A certain amount of engine oil will be consumed while driving. In th e following situations,
oil consumption may increase, and engine oil may need to be refilled in between oil
maintenance intervals. ●
When the engine is new, for example directly after purchasing the vehicle or after
replacing the engine ●
If low quality oil or oil of an inappropriate viscosity is used●
When driving at high engine speeds or with a heavy load, when towing, or when driving
while accelerating or decelerating frequently ●
When leaving the engine idling for a long time, or when drivin g frequently through
heavy trafficEngine oil selection → P. 714
Oil quantity (Low → Full) 1.9 qt. (1.8 L, 1.6 Imp. qt.)
Items Clean funnel1
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3

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
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4

6017-3. Do-it-yourself maintenance
7
Maintenance and care
RX450h_RX450hL _U_OM48F85UThe coolant level is satisfactory if it is between the “FULL” and “LOW” lines on
the reservoir when the hybrid system is cold. ■
Engine coolant reservoir
Reservoir cap
“FULL” line
“LOW” line If the level is on or below the “LOW”
line, add coolant up to the “FULL”
line. ( → P. 702)
■
Power control unit coolant reservoir
Reservoir cap
“FULL” line
“LOW” line If the level is on or below the “LOW”
line, add coolant up to the “FULL”
line. ( → P. 702)■
Coolant selection
Only use “Toyota Super Long Life Coolant” or a similar high qu ality ethylene glycol
based non-silicate, non-amine, non-nitrite, and non-borate coolant with long-life hybrid
organic acid technology.
U.S.A.:
“Toyota Super Long Life Coolant” is a mixt ure of 50% coolant and 50% deionized water.
(Minimum temperature: -31 ° F [-35 ° C])
Canada:
“Toyota Super Long Life Cool ant” is a mixture of 55% coolant and 45% deionized water.
(Minimum temperature: -44 ° F [-42 ° C])
For more details about coolant, contact your Lexus dealer.■
If the coolant level drops within a short time of replenishing
Visually check the radiator, hoses, engine/power control unit coolant reservoir caps,
drain cock and water pump.
If you cannot find a leak, have your Lexus de aler test the cap and check for leaks in the
cooling system.Coolant 1
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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.

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.

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.

6057-3. Do-it-yourself maintenance
7
Maintenance and care
RX450h_RX450hL _U_OM48F85U 
RX450h
The 12-volt battery is located in the
left-hand side of luggage compart-
ment. 
RX450hL
The 12-volt battery is located in the
left-hand side of luggage compart-
ment.12-volt battery Location

606 7-3. Do-it-yourself maintenance
RX450h_RX450hL _U_OM48F85U 
RX450h
Lift the deck board and attach the hook. ( → P. 544)
Remove the cover after removing
the clips.
Press
Pull out 
RX450hL
Remove the deck board and side auxiliary box cover. ( → P. 545)
Remove the 12-volt battery cover.
Remove the deck side trim cover.Removing the 12-volt battery cover 1
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