engine LEXUS RX450H 2019 Repair Manual

6047-3. Do-it-yourself maintenance
RX450h_RX450hL_U
If 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.

6327-3. Do-it-yourself maintenance
RX450h_RX450hL_U
Turn the power 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.
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6578-2. Steps to take in an emergency
8
When trouble arises
RX450h_RX450hL_U
■While towing
If the engine is not running, the power assist for the brakes and steering will not function,
marking steering and braking more difficult.
■Wheel nut wrench
Wheel nut wrench is installe d in luggage compartment. ( P. 674)
WARNING
Observe the following precautions.
Failure to do so may result in death or serious injury.
■When towing the vehicle
■While towing
●When towing using cables or chains, avoid sudden starts, etc. which place excessive
stress on the towing eyelets, cables or chains. The towing eyelets, cables or chains
may become damaged, broken debris ma y hit people, and cause serious damage.
●Do not turn the power switch off.
There is a possibility that the steering wheel is locked and cannot be operated.
■Installing towing eyelets to the vehicle
Make sure that towing eyel ets are installed securely.
If not securely installed, towing ey elets may come loose during towing.
Be sure to transport the vehicle with all four
wheels raised off the ground. If the vehicle is
towed with the tires contacting the ground, the
drivetrain or related parts may be damaged,
the vehicle may fly off the truck, or electricity
generated by the operation of the motor may
cause a fire to occur depending on the nature
of the damage or malfunction.

6598-2. Steps to take in an emergency
8
When trouble arises
RX450h_RX450hL_U
●Fluid leaks under the vehicle
(Water dripping from the air conditioning after use is normal.)
●Flat-looking tires or uneven tire wear
●Engine coolant temperature gauge needle continually points higher than nor-
mal
●Changes in exhaust sound
●Excessive tire squeal when cornering
●Strange noises related to the suspension system
●Pinging or other noises related to the hybrid system
●Engine missing, stumbling or running roughly
●Appreciable loss of power
●Vehicle pulls heavily to one side when braking
●Vehicle pulls heavily to one side when driving on a level road
●Loss of brake effectiveness, spongy feeling, pedal almost touches the floor
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably needs
adjustment or repair. Contact your Lexus dealer as soon as possible.
Visible symptoms
Audible symptoms
Operational symptoms

6608-2. Steps to take in an emergency
RX450h_RX450hL_U
If a warning light turns on or a warning buzzer
sounds
Calmly perform the following actions if any of the warning lights comes on or
flashes. If a light comes on or flashes, but then goes off, this does not necessar-
ily indicate a malfunction in the system. However, if this continues to occur,
have the vehicle inspecte d by your Lexus dealer.
Warning light and warning buzzer list
Warning lightWarning light/Details/Actions
(U.S.A.)
(Canada)
Brake system warning light Indicates that:
• The brake fluid level is low; or
• The brake system is malfunctioning
 Immediately stop the vehicle in a safe place and contact your
Lexus dealer. Continuing to drive the vehicle may be dangerous.
Brake system warning light
Indicates a malfunction in:
• The regenerative braking system;
• The electronically controlled brake system; or
• The electric parking brake
 Have the vehicle inspected by your Lexus dealer immediately.
(If equipped)
Charging system warning light
Indicates a malfunction in the vehicle’s charging system
 Immediately stop the vehicle in a safe place and contact your
Lexus dealer. Continuing to drive the vehicle may be dangerous.
(U.S.A.)
(Canada)
Malfunction indicator lamp Indicates a malfunction in:
• The hybrid system;
• The electronic engine control system; or
• The electronic throttle control system
 Have the vehicle inspected by your Lexus dealer immediately.
SRS warning light
Indicates a malfunction in:
• The SRS airbag system;
• The front passenger occupant classification system; or
• The seat belt pretensioner system
 Have the vehicle inspected by your Lexus dealer immediately.

6688-2. Steps to take in an emergency
RX450h_RX450hL_U
*: A buzzer sounds the first time a message is shown on the multi-information display.
●If the following messages are shown, there may be a malfunction.
Immediately stop the vehicle in a safe place and contact your Lexus dealer.
Continuing to drive the vehicle may be dangerous. • “Braking Power Low Stop in a Safe Place See Owner’s Manual”
• “Oil Pressure Low Stop in a Safe Place See Owner’s Manual”
• “Charging System Malfunction See Owner’s Manual”
●If the following messages are shown, there may be a malfunction.
Immediately have the vehicle inspected by your Lexus dealer.• “Hybrid System Malfunction”
•“Check Engine”
• “Hybrid Battery System Malfunction”
• “Accelerator System Malfunction”
• “Access System with Elec. Key Malfunction See Owner’s Manual”
●If “Engine Coolant Temp High Stop in a Safe Place See Owner’s Manual” is
displayed, following the instructions, accordingly. ( P. 702)
FlashesSounds
Indicates a situation, such as when
damage to the vehicle or danger may
result
Comes
onDoes not sound
Indicates a condition, such as malfunc-
tion of electrical components, their
condition, or indicates the need for
maintenance
FlashesDoes not sound
Indicates a situation, such as when an
operation has been performed incor-
rectly, or indicates how to perform an
operation correctly
If a message instructing to refer to the Owner’s Manual is displayed
System
warning
lightWarning buzzer*Warning

6708-2. Steps to take in an emergency
RX450h_RX450hL_U
■If “Shift Is in N Release Accelerator Before Shifting” is shown
Message is displayed when the accelerator pedal has been depressed and
the shift lever is in N. Release the accelerator pedal and shift the shift lever to
D or R.
■If “Depress Brake when Vehicle Is Stopped Hybrid System May Overheat”
is shown
Message is displayed when the accelerato r pedal is depressed to maintain the
vehicle position when stopped on a upward slope, etc.
If this continues, the hybrid system may overheat.
Release the accelerator pedal and depress the brake pedal.
■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 hybrid system is star ted, increase the engine speed slightly
and maintain it at that speed for approximately 5 minutes to recharge the 12-
volt battery.
■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 Malfunction 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)

6718-2. Steps to take in an emergency
8
When trouble arises
RX450h_RX450hL_U
■If “Forward Camera System Unavailable” or “Forward Camera System
Unavailable Clean Windshield” is displayed
The following systems may be suspended until the problem shown in the mes-
sage is resolved. (P. 296)
●PCS (Pre-Collision System)
●LKA (Lane-Keeping Assist)
●Dynamic radar cruise control with full-speed range
●Automatic High Beam
■If “Oil Maintenance Required Soon” is shown
Indicates that the engine oil is scheduled to be changed.
Check the engine oil, and change if necessary. After changing the engine oil,
the message should be reset. ( P. 600)
■If “Oil Maintenance Required” is shown
Indicates that the engine oil should be changed.
Check and change the engine oil, and o il filter by your Lexus dealer. After
changing the engine oil, the message should be reset. ( P. 600)
■If “Maintenance Required Soon” is displayed (U.S.A. only)
Indicates that all maintenance according to the driven distance on the mainte-
nance schedule
* should be performed soon.
Comes on approximately 4500 miles (7200 km) after the message has been
reset.
If necessary, perform maintenance. Plea se reset the message after the main-
tenance is performed. ( P. 588)
*: Refer to the separate “Scheduled Mainte nance” or “Owner’s Manual Supplement”
for the maintenance interval applicable to your vehicle.

6888-2. Steps to take in an emergency
RX450h_RX450hL_U
WARNING
■When using the compact spare tire
●Remember that the compact spare tire provided is specifically designed for use with
your vehicle. Do not use your comp act spare tire on another vehicle.
●Do not use more than one compact spare tire simultaneously.
●Replace the compact spare tire with a standard tire as soon as possible.
●Avoid sudden acceleration, abrupt steering, sudden braking and shifting operations
that cause sudden engine braking.
■When the compact spare tire is attached
The vehicle speed may not be correctly detected, and the following systems may not
operate correctly:
Also, not only can the following system not be utilized fully, but it may even negatively
affect the drive-train components:
•E-Four
■Speed limit when using the compact spare tire
Do not drive at speeds in excess of 50 mph (80 km/h) when a compact spare tire is
installed on the vehicle.
The compact spare tire is not designed for driving at high speeds. Failure to observe
this precaution may lead to an accident causing death or serious injury.
■After using the tools and jack
Before driving, make sure all the tools and jack are securely in place in their storage
location to reduce the possibilit y of personal injury during a collision or sudden brak-
ing.
• ABS & Brake assist
•VSC
•TRAC
•EPS
• Trailer Sway Control
•VDIM
• Adaptive Variable Suspension System (if equipped)
• Dynamic radar cruise control with full- speed range
• PCS (Pre-Collision System)
• LKA (Lane-Keeping Assist) • Automatic High Beam
• AFS (Adaptive Front-lighting System)
(if equipped)
• Tire pressure warning system
• Intuitive parking assist (if equipped)
• Intelligent Clearance Sonar (ICS) (if equipped)
• Lexus parking assist monitor (if equipped)
• Panoramic view monitor (if equipped)
• BSM (Blind Spot Monitor) (if
equipped)
• Navigation system (if equipped)

6968-2. Steps to take in an emergency
RX450h_RX450hL_U
Remove the engine cover.
Connect the jumper cables according to the following procedure:
Connect a positive jumper cable clamp to the exclusive jump starting ter-
minal on your vehicle.
Connect the clamp on the other end of the positive cable to the positive (+)
battery terminal on the second vehicle.
Connect a negative cable clamp to the negative (-) battery terminal on the
second vehicle.
Connect the clamp at the other end of th e negative cable to a solid, station-
ary, unpainted meta llic point away from the excl usive jump starting terminal
and any moving parts, as shown in the illustration.4
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