check engine LEXUS RX450H 2020 Owners Manual

TABLE OF CONTENTS6
RX350/RX350L_U
7-1. Maintenance and careCleaning and protecting the vehicle exterior ................ 576
Cleaning and protecting the vehicle interior................... 581
7-2. Maintenance Maintenance requirements ............................ 584
General mainte nance.............. 586
Emission inspection and maintenance (I/M)
programs....................................589
7-3. Do-it-yourself maintenance
Do-it-yourself service precautions................................590
Hood ............................................... 592
Positioning a floor jack ............ 593
Engine compartment ............... 594
Tires ................................................. 604
Tire inflation pressure ................613
Wheels .............................................616
Air conditioning filter ................ 618
Windshield wiper inserts ..........621
Electronic key battery.............. 623
Checking and replacing fuses.............................................. 625
Headlight aim .............................. 628
Light bulbs .................................... 630 8-1. Essential information
Emergency flashers .................. 644
If your vehicle has to be stopped in
an emergency .......................... 645
8-2. Steps to take in an emergency
If your vehicle needs to be towed ............................... 646
If you think something is wrong........................................... 652
Fuel pump shut off system...... 653
If a warning light turns on or a warning buzzer
sounds ......................................... 654
If a warning message is displayed ......................................661
If you have a flat tire .................. 666
If the engine will not start ........ 682
If the electronic key does not operate properly ............. 684
If the vehicle battery is discharged................................. 687
If your vehicle overheats......... 692
If the vehicle becomes stuck ............................................. 695
7Maintenance and care8When trouble arises

8
RX350/RX350L_UPlease note that this manual applies to all
models and explains all equipment, including
options. Therefore, you may find some expl anations for equipment not installed on your
vehicle.
All specifications provided in this manual are current at the time of printing. However,
because of the Lexus policy of continual pr oduct improvement, we reserve the right to
make changes at any time without notice.
Depending on specifications, th e vehicle shown in the illustrations may differ from your
vehicle in terms of color and equipment.
Approximately five hours after the engine is turned off, you may hear sound coming from
under the vehicle for several minutes. This is the sound of a fuel evaporation leakage
check and, it does not indicate a malfunction.
A wide variety of non-genuine spare parts and accessories for Lexus vehicles are cur-
rently available in the market. You should kn ow that Toyota does not warrant these prod-
ucts and is not responsible fo r their performance, repair, or replacement, or for any
damage they may cause to, or adverse effect they may have on, your Lexus vehicle.
This vehicle should not be modified with non-genuine Lexus products. Modification with
non-genuine Lexus products could affect its performance, safety or durability, and may
even violate governmental regulations. In addition, damage or performance problems
resulting from the modification may not be covered under warranty.
The installation of a mobile two-way radio system in your vehicle could affect electronic
systems such as:
●Multiport fuel injection system/seque ntial multiport fuel injection system
●Lexus Safety System+
●Anti-lock brake system
●Vehicle dynamics integrated management
●SRS airbag system
●Seat belt pretensioner system
Be sure to check with your Lexus dealer for precautionary measures or special instruc-
tions regarding installation of a mobile two-way radio system.
For your information
Main Owner’s Manual
Noise from under vehicle after turning off the engine
Accessories, spare parts and modification of your Lexus
Installation of a mobile two-way radio system

15Pictorial index
RX350/RX350L_U
Windshield wipers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 261
Precautions for winter season. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 384
To prevent freezing (windshield wiper de-icer)
*. . . . . . . . . . . . . . . . . . . . . . . . P. 513
Precautions against car wash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 578
Fuel filler door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 269
Refueling method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 271
Fuel type/fuel tank capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 700
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 604
Tire size/inflation pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 704
Winter tires/tire chain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 38 4
Checking/rotation/tire pressure warning system . . . . . . . . . . . . . . . . . . . . . . P. 604
Coping with flat tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 666
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 592
Opening. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 592
Engine oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 700
Coping with overheat. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 692
Headlights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 252
Turn signal lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 2 46
Parking lights/daytime running lights. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 252
Front side marker lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 252
Fog lights. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 260
Cornering lights
*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 253
Stop/tail lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P . 252
License plate lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 252
Back-up lights
Shifting the shift lever to R . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 240
Rear side marker lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .P. 252
4
5
6
7
Light bulbs of the exte rior lights for driving
(Replacing method: P. 630, Watts: P. 705)
*: If equipped
8
9
10
11
12
13
14
15
16
17

291-1. For safe use
1
For safety and security
RX350/RX350L_U
WARNING
Observe the following precautions.
Failure to do so may cause the driver’s floor mat to slip, possibly interfering with the ped-
als while driving. An unexpectedly high spee d may result or it may become difficult to
stop the vehicle. This could lead to an ac cident, resulting in death or serious injury.
■When installing the driver’s floor mat
●Do not use floor mats designed for other models or different model year vehicles,
even if they are Lexus Genuine floor mats.
●Only use floor mats designed for the driver’s seat.
●Always install the floor mat securely using the retain ing hooks (clips) provided.
●Do not use two or more floor mats on top of each other.
●Do not place the floor mat bottom-side up or upside-down.
■Before driving
●Check that the floor mat is securely fixed in
the correct place with all the provided retain-
ing hooks (clips). Be especially careful to per-
form this check after cleaning the floor.
●With the engine stopped and the shift lever in
P, fully depress each pedal to the floor to
make sure it does not interfere with the floor
mat.

531-1. For safe use
1
For safety and security
RX350/RX350L_U
Exhaust gas precautions
Harmful substance to the human body is contained in exhaust gases if inhaled.
WARNING
Exhaust gases contain harmful carbon monoxi de (CO), which is colorless and odorless.
Observe the following precautions.
Failure to do so may cause exhaust gases enter the vehicle and may lead to an accident
caused by light-deadness, or may lead to death or a serious health hazard.
■Important points while driving
●Keep the back door closed.
●If you smell exhaust gases in the vehicle even when the back door is closed, open the
windows and have the vehicle inspected at your Lexus dealer as soon as possible.
■When parking
●If the vehicle is in a poorly ventilated area or a closed area, such as a garage, stop the
engine.
●Do not leave the vehicle with the engine running for a long time.
If such a situation cannot be avoided, park the vehicle in an open space and ensure
that exhaust fumes do not enter the vehicle interior.
●Do not leave the engine running in an area with snow build-up, or where it is snowing.
If snowbanks build up around the vehicle while the engine is running, exhaust gases
may collect and enter the vehicle.
■Exhaust pipe
The exhaust system needs to be checked periodically. If there is a hole or crack caused
by corrosion, damage to a joint or abnormal exhaust noise, be sure to have the vehicle
inspected and repaired by your Lexus dealer.

771-3. Theft deterrent system
1
For safety and security
RX350/RX350L_U
The alarm uses light and sound to give an alert when an intrusion is detected.
The alarm is triggered in the following situations when the alarm is set:
●A locked door is unlocked or opened in any way other than using the entry
function, wireless remote control or mech anical key. (The doors will lock again
automatically.)
●The hood is opened.
Close the doors and hood, and lock all
the doors. The system will be set auto-
matically after 30 seconds.
The indicator light changes from being
on to flashing when the system is set.
Do one of the following to de activate or stop the alarms:
●Unlock the doors.
●Turn the engine switch to ACCESSOR Y or IGNITION ON mode, or start
the engine. (The alarm will be deactivat ed or stopped after a few seconds.)
■System maintenance
The vehicle has a maintenance-free type alarm system.
■Items to check before locking the vehicle
To prevent unexpected triggering of the alarm and vehicle theft, make sure of the follow-
ing:
●Nobody is in the vehicle.
●The windows and moon roof or panoramic mo on roof are closed before the alarm is
set.
●No valuables or other personal items are left in the vehicle.
Alarm
The alarm
Setting the alarm system
Deactivating or stopping the alarm

822. Instrument cluster
RX350/RX350L_U
*1: These lights turn on when the engine switch is turned to IGNITION ON mode to indicate that a system check is being performed. They will turn off after the engine is
started, or after a few seconds. There may be a malfunction in a system if a light does
not come on, or turn off. Have the ve hicle inspected by your Lexus dealer.
*2: This light flashes to indicate a malfunction.
*3: This light flashes or illuminates to indicate a malfunction.
*4: This light illuminates on the center panel.
*5:RX350
*6:RX350L
The indicators inform the driver of the op erating state of the vehicle’s various sys-
tems.
Low fuel level warning light
(  P. 656)*4, 6Rear passengers’ seat
belt reminder light
( P. 656)
Driver’s and front
passenger’s seat belt
reminder light ( P. 656)
*1Tire pressure warning light
( P. 656)
*4, 5Rear passengers’ seat
belt reminder light
( P. 656)*1Master warning light
( P. 657)
Indicators
Turn signal indicator
( P. 246) Fog light indicator
(
 P. 260)
(U.S.A.)
Headlight indicator
( P. 252) Cruise control indicator
(
 P. 300)
(Canada)
Tail light indicator
( P. 252) Radar cruise control
indicator (
P. 300)
Headlight high beam
indicator ( P. 253) Cruise control “SET”
indicator (
P. 300)
*1Automatic High Beam
indicator ( P. 256) LKA indicator (
P. 291)

842. Instrument cluster
RX350/RX350L_U
●Drive mode indicators
Except F SPORT models
F SPORT models
*1: These lights turn on when the engine switch is turned to the IGNITION ON mode to indicate that a system check is being performed. They will turn off after the engine is
started, or after a few seconds. There may be a malfunction in a system if a light does
not come on, or turn off. Have the ve hicle inspected by your Lexus dealer.
*2: In order to confirm operation, the BSM ou tside rear view mirror indicators illuminate
in the following situations:
• When the BSM function is enabled on of the multi-information display, the
engine switch is turned to IGNITION ON mode.
• When the engine switch is in IGNITION ON mode, the BSM function is enabled
on of the multi-information display.
If the system is functioning correctly, the BSM outside rear view mirror indicators will
turn off after a few seconds.
If the BSM outside rear view mirror indicators do not illuminate or do not turn off,
there may be a malfunction in the system.
If this occurs, have the vehicle inspected by your Lexus dealer.
*3: This light illuminates on the outside rear view mirrors.
*4: This light flashes to indicate that the system is operating.
*5: The light comes on when the system is turned off.
*6: This light illuminates on the center panel.
*7: When the outside temperature is approximately 37 F (3 C) or lower, this indicator
will flash for approximately 10 seconds, then stay on. Eco drive mode indicator
(
 P. 373) “SPORT” indicator
(
 P. 373)
Eco drive mode indicator
( P. 373) “SPORT S” indicator
(
 P. 373)
“SPORT S+” indicator
(  P. 373) “CUSTOMIZE” indicator
(
 P. 373)

892. Instrument cluster
2
Instrument cluster
RX350/RX350L_U
■The meters and display illuminate when
The engine switch is in IGNITION ON mode.
■Brightness of the meters (day mode and night mode)
The brightness of the meters is changed between day mode and night mode.
●Day mode: When the tail lights are off or when the tail lights are on but the surrounding
area is bright
●Night mode: When the tail lights are on and the surrounding area is dark
■Outside temperature display
●In the following situations, the correct outside temperature may not be displayed, or the
display may take longer than normal to change:
• When stopped, or driving at low speeds (less than 12 mph [20 km/h])
• When the outside temperature has changed suddenly (at the entrance/exit of a garage, tunnel, etc.)
●When “ ” or “E” is displayed, the sy stem may be malfunctioning.
Take your vehicle to your Lexus dealer.
■Clock settings screen (vehicles with a navigation system only)
If the clock adjustment screen is displayed continuously when attempting to change the
clock settings, the system may be malfunctioning.
Have the vehicle inspected by your Lexus dealer.
■Customization
Some functions can be customized. ( P. 97)
NOTICE
■To prevent damage to the engine and its components
●Do not let the indicator needle of the tachometer enter the red zone, which indicates
the maximum engine speed.
●The engine may be overheating if the engine coolant temperature gauge is in the red
zone (H). In this case, immediately stop the vehicle in a safe place, and check the
engine after it has cooled completely. ( P. 692)

1122. Instrument cluster
RX350/RX350L_U
■Head-up display
The head-up display may seem dark or hard to see when viewed through sunglasses,
especially pola rized sunglasses.
Adjust the brightness of the head-up display or remove your sunglasses.
■When the battery is disconnected
The customize settings of the head-up display will be reset.
■Display brightness
The brightness of the head-up display can be adjusted on of the multi-information
display. Also, it is automatically adju sted according to the ambient brightness.
■Enabling/disabling of the head-up display
If the head-up display is disabled, it will rema in disabled when the engine switch is turned
off then back to IGNITION ON mode.
■Automatic adjustment of the head-up display position
A desired head-up display position can be entered to memory and recalled automati-
cally by the driving position memory system. ( P. 172)
■Street name display (vehicle s with a navigation system)
Only street names which are included in the map data will be displayed.
WARNING
■Before using the head-up display
●Check that the position and brightness of the head-up display image does not inter-
fere with safe driving. Inco rrect adjustment of the image’s position or brightness may
obstruct the driver’s view and lead to an acc ident, resulting in death or serious injury.
●Do not continuously look at the head-up di splay while driving as you may fail to see
pedestrians, objects on the road, etc. ahead of the vehicle.
■Caution for changing settings of the head-up display
As the engine needs to be running while changing the settings of the head-up display,
ensure that the vehicle is parked in a place with adequate ventilation. In a closed area
such as a garage, exhaust gases including harmful carbon monoxide (CO) may collect
and enter the vehicle. This may lead to death or a serious health hazard.