2018 LEXUS LS500 check engine

382 6-3. Do-it-yourself maintenance
LS500_OM_OM50F54U_(U) “F” line
“L” lineIf the level is on or below the “L” line, add
coolant up to the “F” line. ( → P.443)■
Intercooler coolant reservoir
The coolant level is satisfactory if it is
between the “F” and “L” lines on the
reservoir when the engine is cold.
Reservoir cap
“F” line
“L” lineIf the level is on or below the “L” line, add
coolant up to the “F” line. ( → P.443)
■
Coolant selection
Only use “Toyota Super Long Life Coolant”
or a similar high quality 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 mix-
ture of 50% coolant and 50% deionized
water. (Minimum temperature: -31°F
[-35°C])
Canada:
“Toyota Super Long Life Coolant” is a mix-
ture 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 radi ator, hoses, engine
coolant reservoir caps, drain cock and
water pump.
If you cannot find a leak, have your Lexus
dealer test the cap and check for leaks in
the cooling system.
Check the radiator, condenser, inter-
cooler radiator and intercooler sub
radiator and clear away any foreign
objects. If either of the above parts is
extremely dirty or yo u are not sure of
their condition, have your vehicle
inspected by your Lexus dealer.B
C
A
B
C WARNING■
When the engine is hot
Do not remove the engine coolant reser-
voir cap, the intercooler coolant reser-
voir cap and the coolant inlet cap.
( → P.445)
The cooling system may be under pres-
sure and may spray hot coolant if the cap
is removed, causing serious injuries, such
as burns.
NOTICE■
When adding coolant
Coolant is neithe r plain water nor
straight antifreeze. The correct mixture
of water and antifreeze must be used to
provide proper lubrication, corrosion
protection and cooling. Be sure to read
the antifreeze or coolant label.
■
If you spill coolant
Be sure to wash it off with water to pre-
vent it from damaging parts or paint.
Checking the radiator, con-
denser, intercooler radiator (if
equipped) and intercooler sub
radiator (if equipped)

3836-3. Do-it-yourself maintenance
LS500_OM_OM50F54U_(U) 6
Maintenance and care ■
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.
 Fluid type FMVSS No.116 DOT 3 or SAE J1703
brake fluid
FMVSS No.116 DOT 4 or SAE J1704
brake fluid
 Item Clean funnel
■
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. If any washer does not work or the
warning message appears on the
multi-information display, the washer
tank may be empty. Add washer fluid.WARNING■
When the engine is hot
Do not touch the radiator, condenser,
intercooler radiator or intercooler sub
radiator as they may be hot and cause
serious injuries, such as burns.
Checking and adding the brake
fluid WARNING■
When filling the reservoir
Take care as brake fluid can harm your
hands and eyes and damage painted sur-
faces.
If fluid gets on your hands or in your eyes,
flush the affected area with clean water
immediately.
If you still experience discomfort, 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 leve l in the accumulator
is high.
If the reservoir need s frequent refilling,
there may be a serious problem.
Adding the washer fluid
WARNING
■
When adding washer fluid
Do not add washer fluid when the engine
is hot or running as washer fluid contains
alcohol and may catch fire if spilled on
the engine, etc.

3896-3. Do-it-yourself maintenance
LS500_OM_OM50F54U_(U) 6
Maintenance and care before serious problems arise.
 The tire pressure detected by the
tire pressure warning system can be
displayed on the multi-information
display. ( → P.76)
 If the tire pressure drops below a
predetermined level, the driver is
warned by a screen display and a
warning light. ( → P.422)
■
Routine tire inflation pressure checks
The tire pressure warning system does not
replace routine tire inflation pressure
checks. Make sure to check tire inflation
pressure as part of your routine of daily
vehicle checks.
■
Tire inflation pressure
●
It may take a few minutes to display the
tire inflation pressure after the engine
switch is turned to IGNITION ON mode.
It may also take a few minutes to display
the tire inflation pres sure after inflation
pressure has been adjusted.
●
Tire inflation pressu re changes with tem-
perature. The displayed values may also be different from the values measured
using a tire pressure gauge. ■
Situations in which the tire pressure
warning system may not operate prop-
erly ●
In the following cases, the tire pressure
warning system may not operate prop-
erly.
• If non-genuine Lexus wheels are used.
• If a tire has been replaced with a tire that
is not an OE (Original Equipment) tire.
• If a tire has been replaced with a tire that
is not of the specified size.
• If tire chains, etc. are installed.
• An auxiliary-supported run-flat tire is
equipped.
• If a window tint that affects the radio wave
signals is installed.
• If there is a lot of snow or ice on the vehi-
cle, particularly around the wheels or
wheel housings.
• If the tire inflation pressure is much higher
than the specified level.
• If wheels not equipped with tire pressure
warning valves and transmitter are used.
• If the ID code on the tire pressure warn-
ing valves and transmitters is not regis-
tered in the tire pressure warning
computer. ●
Performance may be af fected in the fol-
lowing situations.
• When driving near a TV tower, electric
power plant, gas stat ion, radio station,
large display, airport or other facility that
generates strong radi o waves or electri-
cal noise
• When carrying a portable radio, cellular
phone, cordless phone or other wireless
communication device
If tire position information is not correctly
displayed due to the radio wave conditions,
the display may be corrected by changing
the location of the vehicle as the radio wave
conditions may change.
●
When the vehicle is stopped, the time
taken for the warning to start or turn off
may be longer.
●
When the inflation pressure of a tire
drops rapidly, for example when a tire has
burst, the warning may not operate.

402 6-3. Do-it-yourself maintenance
LS500_OM_OM50F54U_(U) 1 Turn the engine switch off.
2 Open the glove box. Remove the
partition. ( → P.336)
3 Remove the panel.
4 Unlock the filter cover ( ), pull the
filter cover out of the claws ( ),
and remove the filter cover. 5 Remove the filter case.
6 Remove the air conditioning filter
from the filter case and replace it
with a new one. The “ UP” marks shown on the filter
and the filter case sh ould be pointing up.
■
Checking interval
Inspect and replace the air conditioning fil-
ter according to the maintenance schedule.
In dusty areas or areas with heavy traffic
flow, early replacement may be required.
(For scheduled maintenance information,
please refer to the “Owner’s Manual Sup-
plement” or “Scheduled Maintenance”.)
■
If air flow from the vents decreases dra-
matically
The filter may be clogged. Check the filter
and replace if necessary.
■
Air conditioning filt er with deodorizing
function
When fragrances are placed in your vehi-
cle, the deodorizing effect may become
significantly weakened in a short period.
When an air conditioning odor comes out
continuously, replace the air conditioning Air conditioning filter The air conditioning filter must be
changed regularly to maintain air
conditioning efficiency.
Removing the air conditioning
filter
A
B

4056-3. Do-it-yourself maintenance
LS500_OM_OM50F54U_(U) 6
Maintenance and care 1 Turn the engine switch off.
2 Open the fuse box cover. 
Engine compartment: type A fuse
box Remove the service cover ( → P.379) and
push the tabs in and lift the lid off.

Engine compartment: type B fuse
box Remove the engine compartment cover
( → P.378) and push the ta bs in and lift the
lid off. 
Driver’s side instrument panel Push the tab in and remove the lid.
Make sure to push the tab in during
removal or installation.

Passenger’s side instrument panel Push the tab in and remove the lid.
Make sure to push the tab in during
removal or installation.

Trunk Remove the luggage mat. ( → P.339)
Push the tab in and lift the lid off.Checking and replacing
fuses If any of the electrical components
do not operate, a fuse may have
blown. If this happens, check and
replace the fuses as necessary.
Checking and replacing fuses

426 7-2. Steps to take in an emergency
LS500_OM_OM50F54U_(U) If it is, tighten it securely.
The light will go off after several driving
trips.
If the light does not go off even after several
trips, contact your Lexus dealer as soon as
possible. ■
Electric power steering system warning
light (warning buzzer)
When the battery charge becomes insuffi-
cient or the voltage temporarily drops, the
electric power steeri ng system warning
light may come on and the warning buzzer
may sound. ■
When the tire pressure warning light
comes on
Inspect the tires to check if a tire is punc-
tured.
If a tire is punctured: → P.432
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 wa rning light blinks for
approximately 1 minute then stays on
There may be a malfunction in the tire
pressure warning syst em. Have the vehicle
inspected by your Lexus dealer immedi-
ately. 
If the tire pressure warning light comes
on
1 After the temperature of the tires has
lowered sufficiently, check the inflation
pressure of each tire and adjust them to
the specified level.
2 If the warning light does not turn off
even after several minutes have
elapsed, check that the inflation pres-
sure of each tire is at the specified level
and perform initialization. ( → P.392)
■
The tire pressure warning light may
come on due to natural causes
The tire pressure wa rning light may come
on due to natural causes such as natural air
leaks and tire inflation pressure changes
caused by temperature. In this case, adjust-
ing the tire inflation pressure will turn off the
warning light (after a few minutes). ■
Conditions that the tire pressure warn-
ing system may not function properly
→ P.389
WARNING■
If both the ABS and the brake system
warning lights remain on
Stop your vehicle in a safe place immedi-
ately and contact your Lexus dealer.
The vehicle will become extremely
unstable during br aking, and the ABS
system may fail, which could cause an
accident resulting in death or serious
injury. ■
When the electric power steering
system warning light comes on
When the light comes on yellow, the
assist to the power st eering is restricted.
When the light comes on red, the assist
to the power steering is lost and handling
operations of the steering wheel become
extremely heavy.
When steering wheel operations are
heavier than usual, grip the steering
wheel firmly and operate it using more
force than usual. ■
If the tire pressure warning light
comes on
Be sure to observe the following precau-
tions.
Failure to do so could cause a loss of
vehicle control and result in death or
serious injury.
●
Decelerate to the lowest appropriate
speed as soon as possible. Do not
drive over 50 mph (80 km/h).
●
Check and adjust the tire inflation
pressure immediately.
●
If the tire pressure warning light comes
on even after tire inflation pressure
adjustment, it is prob able that you have
a flat tire. Have the flat tire replaced by
the nearest Lexus dealer.

430 7-2. Steps to take in an emergency
LS500_OM_OM50F54U_(U)  In some situations, the master warning light and warning buzzer may not oper-
ate as specified. In this case, follow the instructions displayed in the warning
message.
 If a warning light comes on or flashes at the same time that a warning message is
displayed, take corrective actio n according to the warning light. ( → P.418)*
: A buzzer sounds the first time a message is shown on the multi-information display.
■
Warning messages
The warning messages explained below
may differ from the actual messages
according to operation conditions and vehi-
cle specifications. ■
Warning buzzer
In some cases, the bu zzer may not be heard
due to being in a noisy location or audio
sound. ■
If “Engine Oil Level Low Add or
Replace” is displayed
The engine oil level is low. Check the level
of the engine oil, and add if necessary.
This message may appear if the vehicle is
stopped on a slope. Move the vehicle to a
level surface and check to see if the mes-
sage disappears.
■
If “Engine Stoppe d Steering Power
Low” is displayed
This message is displa yed if the engine is
stopped while driving.
When steering wheel operations are
heavier than usual, grip the steering wheel
firmly and operate it using more force than
usual. ■
If “Auto Power Off to Conserve Battery”
is displayed
Power was turned off due to the automatic
power off function. Next time when starting
the engine, increase the engine speed
slightly and maintain that level for approxi-
mately 5 minutes to recharge the battery. ■
If “Headlight System Malfunction Visit
Your Dealer” is displayed
The following systems may be malfunction-
ing. Have the vehicle inspected by your
Lexus dealer immediately. ●
The LED headlight system ●
AFS (Adaptive Front-lighting System) ●
The automatic headlight leveling system ●
AHB (Automatic High Beam)
■
If “Front Camera Unav ailable” or “Front
Camera Unavailable Remove Debris
On Windshield” is displayed
The following systems may be suspended
until the problem shown in the message is
resolved. ( → P.210, 217, 424)
●
PCS (Pre-Collision system)
●
LTA (Lane Tracing Assist) (if equipped)
●
LKA (Lane Keeping Assist) (if equipped)
●
Dynamic radar cruise control with
full-speed rangeComes on Does not sound Indicates a condition, such as malfunction of electri-
cal components, their cond ition, or indicates the
need for maintenance
Flashes Does not sound Indicates a situation, such as when an operation has
been performed incorrectly, or indicates how to
perform an operation correctlyWarning buzzer *
Warning

4317-2. Steps to take in an emergency
LS500_OM_OM50F54U_(U) 7
When trouble arises ●
RSA (Road Sign Assist) (if equipped)●
AHB (Automatic High Beam)■
If “Maintenance Required Soon” is dis-
played
Indicates that all maintenance according to
the driven distance on the maintenance
schedule *
should be performed soon.
Comes on approximately 4500 miles
(7200 km) after the message has been
reset. If necessary, perform maintenance.
Please reset the message after the mainte-
nance is performed. ( → P.368)*
: Refer to the separa te “Scheduled Main-
tenance” or “Owner’s Manual Supple-
ment” for the maintenance interval
applicable to your vehicle.■
If “Maintenance Required Visit Your
Dealer” is displayed
Indicates that all maintenance is required to
correspond to the driven distance on the
maintenance schedule *
.
Comes on approximately 5000 miles
(8000 km) after the message has been
reset. (The indicator will not work properly
unless the message ha s been reset.) Per-
form the necessary maintenance. Please
reset the message after the maintenance is
performed. ( → P.368)*
: Refer to the separa te “Scheduled Main-
tenance” or “Owner’s Manual Supple-
ment” for the maintenance interval
applicable to your vehicle.
■
If “Oil Maintenance Required Soon” is
displayed
Indicates that the engine oil should be
scheduled to be changed.
Check the engine oil an d change it if neces-
sary. After changing the engine oil, make
sure to reset the message. ( → P.381)
■
If “Oil Maintenance Required” is dis-
played
Indicates that the engine oil should be
changed.
Check and change the en gine oil, and oil fil-
ter by your Lexus deal er. After changing the engine oil, make sure to reset the message.
( → P.381) ■
If “Shift System Malfunction Driving
Unavailable” is displayed
There is a malfunction in the shift control
system. Have the vehicle inspected by your
Lexus dealer immediately. ■
If a message that indicates the need for
the shift lever operation is displayed
To prevent the shift le ver from being oper-
ated incorrectly or the vehicle from moving
unexpectedly, a message that requires shift-
ing the shift position may be displayed on
the multi-information display. In that case,
follow the instruction of the message and
shift the shift position. ■
If a message that indicates the need for
visiting your Lexus dealer is displayed
The system or part shown on the
multi-information display is malfunctioning.
Have the vehicle inspected by your Lexus
dealer immediately. ■
If a message that indicates the need for
referring to Owner’ s Manual is dis-
played ●
If any of the following messages are
shown on the multi-information display,
follow the instructions.
• “Engine Coolant Temp High” ( → P.443)
•“Battery Low” ( → P.438)
• “Transmission Fluid Temp High” ( → P.164)●
If any of the following messages are
shown on the multi-info rmation display, it
may indicate a malf unction. Have the
vehicle inspected by your Lexus dealer
immediately.
• “Access System with Elec. Key Malfunc-
tion”
• “Shift System Malfunction”
• “P Switch Malfunction”
• “Shift System Unavailable”
●
If any of the following messages are
shown on the multi-info rmation display, it
may indicate a malfun ction. Immediately
stop the vehicle and contact your Lexus
dealer.
• “Braking Power Low”
• “Charging System Malfunction”
• “Oil Pressure Low”