check engine LEXUS RX350 2019 Service Manual

5957-3. Do-it-yourself maintenance
7
Maintenance and care
RX350/RX350L_U With 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 engine, 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
2
3
4
5
1
2
3
6

596 7-3. Do-it-yourself maintenance
RX350/RX350L_U ■
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. 701
Oil quantity (Low  Full) 1.9 qt. (1.8 L, 1.6 Imp. qt.)
Items Clean funnel1
2
3

5977-3. Do-it-yourself maintenance
7
Maintenance and care
RX350/RX350L_U ■
After changing the engine oil
The engine oil maintenance data should be reset. Perform the following procedures:
Select on the multi-information display. (  P. 97)
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

598 7-3. Do-it-yourself maintenance
RX350/RX350L_U The coolant level is satisfactory if it is between the “FULL” and “LOW” lines on
the reservoir when the engine is cold.
Reservoir cap
“FULL” line
“LOW” line If the level is on or below the “LOW”
line, add coolant up to the “FULL” line.
(  P. 692)■
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 coolant reservoir cap, 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
2
3
WARNING ■
When the engine is hot
Do not remove the engine coolan t reservoir cap 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.

5997-3. Do-it-yourself maintenance
7
Maintenance and care
RX350/RX350L_U Check 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. 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 engine is hot
Do not touch the radiator or condenser as they may be hot and cause serious injuries,
such as burns.

6017-3. Do-it-yourself maintenance
7
Maintenance and care
RX350/RX350L_U Check the battery as follows. ■
Battery exterior Make sure that the battery terminals are not corroded and that there are no
loose connections, cracks, or loose clamps.
Terminals
Hold-down clamp ■
Before recharging
When recharging, the battery produces hydrogen gas which is flammable and explosive.
Therefore, observe the following precautions before recharging: ●
If recharging with the 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 battery. ■
After recharging/reconnecting the battery ●
The engine may not start. Follow the pr ocedure below to in itialize the system.
Shift the shift lever to P.
Open and close any of the doors.
Restart the engine.●
Unlocking the doors using the smart access system with push-button start may not be
possible immediately after reconnecting the battery. If this happens, use the wireless
remote control or the mechanical key to lock/unlock the doors.●
Start the engine with the engine switch in ACCESSORY mode. The engine may not
start with the engine switch turned off. However, the engine will operate normally from
the second attempt. ●
The engine switch mode is recorded by the vehicle. If the battery is reconnected, the
vehicle will return the engine switch mode to the status it was in before the battery was
disconnected. Make sure to turn off the power before disconnect the battery. Take
extra care when connecting the battery if the engine 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.Battery 1
2
1
2
3

6257-3. Do-it-yourself maintenance
7
Maintenance and care
RX350/RX350L_U Turn the engine switch off.
Open the fuse box cover. 
Engine compartment
Push the tab in and lift the lid off. 
Driver’s side instrument panel
Remove the lid.Checking and replacing fuses If any of the electrical components do not operate, a fuse may have blown. If
this happens, check and repl ace the fuses as necessary.1
2

642 7-3. Do-it-yourself maintenance
RX350/RX350L_U ■
LED lights
The headlight low beams, headlight high beams, front turn signal lights (vehicles with tri-
ple-beam headlights), parking lights and da ytime running lights, fog lights, cornering
lights (if equipped), front side marker lights (vehicles with triple-b eam headlights), side
turn signal lights, stop/tail lights, rear turn signal light (vehicles with triple-beam head-
lights), rear side marker lights, high mounted stoplight, license plate lights, and outer foot
lights consist of a number of LEDs. If any of the LEDs has burned out, take your vehicle to
your Lexus dealer to have the light replaced. ■
Condensation build-up on the inside of a lens
Temporary condensation build-up on the inside of the headlight lens does not indicate a
malfunction. Contact your Lexus dealer for mo re information in the following situations:●
Large drops of water have built up on the inside of a lens. ●
Water has built up inside a headlight. ■
When replacing light bulbs
 P. 626
WARNING ■
To prevent injury
Before performing any light bulb replacement procedure, be sure to turn the engine
switch off. Failure to do so may result in burns from hot components or a part of your
body may get caught on an operating co mponent, possibly causing serious injury.■
Replacing light bulbs ●
Turn off the lights. Do not attempt to replac e the bulb immediately after turning off the
lights.
The bulbs become very hot and may cause burns. ●
Do not touch the glass portion of the light bu lb with bare hands. When it is unavoid-
able to hold the glass portion, use and hold with a clean dry cloth to avoid getting
moisture and oils on the bulb.
Also, if the bulb is sc ratched or dropped, it may blow out or crack.●
Fully install light bulbs and any parts used to secure them. Failure to do so may result
in heat damage, fire, or water entering th e headlight unit. This may damage the head-
lights or cause condensation to build up on the lens.●
Do not attempt to repair or disassemble th e light bulbs, connector s, electric circuits
or component parts.
Doing so may result in death or se rious injury due to electric shock.■
To prevent damage or fire ●
Make sure bulbs are fully seated and locked. ●
Check the wattage of the bulb before installing to prevent heat damage.

658 8-2. Steps to take in an emergency
RX350/RX350L_U ■
If the malfunction indicator lamp comes on while driving
First check the following: ●
Is the fuel tank empty?
If it is, fill the fu el tank immediately.●
Is the fuel tank cap loose?
If it is, tighten it securely.
The light will go off after several driving trips.
If the light does not go off even after severa l trips, contact your Lexus dealer as soon as
possible. ■
When the tire pressure warning light comes on
Inspect the tires to check if a tire is punctured.
If a tire is punctured:  P. 666
If none of the tires are punctured:
Turn the engine switch off then turn it to IGNITION ON mode. Check if the tire pressure
warning light comes on or blinks. 
If the tire pressure warning light comes on
After the temperature of the tires has lowere d sufficiently, check the inflation pressure
of each tire and adjust th em to the specified level.
If the warning light does not turn off even after several minutes have elapsed, check
that the inflation pressure of each tire is at the specified level an d perform initialization.
(  P. 606)
If the warning light does not turn off severa l minutes after the init ialization has been per-
formed, have the vehicle inspected by your Lexus dealer immediately. 
If the tire pressure wa rning light blinks for 1 minute then stays on
There may be a malfunction in the tire pressure warnin g system. Have the vehicle
inspected by your Lexus dealer immediately. ■
The tire pressure warning light ma y come on due to natural causes
The tire pressure warning light may come on due to natural causes such as natural air
leaks and tire inflation pressure changes caus ed by temperature. In this case, adjusting
the tire inflation pressure will turn off the warning light (aft er a few minutes).■
When a tire is replaced with a spare tire
The compact spare tire is not equipped with a tire pressure warning valve and transmit-
ter. If a tire goes flat, the tire pressure warning light will not turn off even though the flat
tire has been replaced with the spare tire. Replace the spare tire with the repaired tire
and adjust the tire inflation pressure. The tire pressure warnin g light will go off after a few
minutes. ■
Conditions that the tire pressure wa rning system may not function properly
 P. 609 ■
Warning buzzer
In some cases, the buzzer ma y not be heard due to being in a noisy location or audio
sound. ■
Customization
Some functions can be customized. (  P. 722)1
2

6638-2. Steps to take in an emergency
8
When trouble arises
RX350/RX350L_U Take the appropriate actions as in structed in the message displayed.
If any of the following messages are displa yed, also refer to this Owner’s Manual.■
If “Shift to P Before Exiting Vehicle” is shown
Message is displayed when the driver’s door is opened without turning the
engine switch off with the shift le ver in any position other than P.
Shift the shift lever to P. ■
If “Power Turned Off to Save Battery” is displayed
This message is displayed when the power was cut off due to the automatic
power off function.
The next time the engine is started, increase the engine speed slightly and
maintain it at that speed for approxim ately 5 minutes to recharge the battery.■
If “AWD System Overheated Switching to 2WD Mode” or “AWD System
Overheated 2WD Mode Engaged” is displayed (AWD models)
This message may be displayed when driving under extremely high load con-
ditions.
Drive the vehicle at low speeds or stop the vehicle in a safe place with the
engine running until the message is cleared.
If the message is not cleared, have the vehicle inspected by your Lexus dealer. ■
If “A New Key has been Registered Contact Your Dealer for Details” is dis-
played
This message will be displayed each time the driver’s door is opened when the
doors are unlocked from the outside fo r approximately one week after a new
electronic key has been registered.
If this message is displayed but you ha ve not had a new electronic key regis-
tered, ask your Lexus dealer to check if an unknown electronic key (other than
those in your possession) has been registered. ■
When “Headlight System Malfunctio n Visit Your Dealer” is displayed
The following systems may be malfunct ioning. Have the vehicle inspected by
your Lexus dealer immediately. ●
The LED headlight system ●
The automatic headlight leveling system ●
Automatic High Beam ●
AFS (Adaptive Front-lighting System) (if equipped)Other messages displayed on the multi-information display