2021 LEXUS LS500 ECU

3866-3. Do-it-yourself maintenance
2Engage the rubber strip to the vehi-
cle body.
With the engine at operating tempera-
ture and turned off, check the oil level
on the dipstick.
■Checking the engine oil
1 Park the vehicle on level ground.
After warming up the engine and
turning it off, wait more than 5 min-
utes for the oil to drain back into the
bottom of the engine.
2 Holding a rag under the end, pull
the dipstick out.
2WD models
AWD models
3 Wipe the dipstick clean.
4 Reinsert the dipstick fully.
5 Holding a rag under the end, pull
the dipstick out and check the oil
level.
Low
Normal
Excessive
The shape of the dipstick may differ
depending on the type of vehicle or
engine.
6Wipe the dipstick and reinsert it
fully.
■Checking the oil type and prepar-
ing the item needed
Make sure to check the oil type and
prepare the items needed before add-
ing oil.
 Engine oil selection
NOTICE
■Checking the service cover after
installation
Make sure that the cover is securely
installed in its original position.
Checking and adding the engine
oil
A
B
C

4146-3. Do-it-yourself maintenance
Type ANormal fuse
Blown fuse
Type B
Normal fuse
Blown fuse
Type CNormal fuse
Blown fuse
Type DNormal fuse
Blown fuse
■After a fuse is replaced
●When installing the lid, make sure that the
tab is installed securely.
●If the lights do not turn on even after the
fuse has been replaced, a bulb may need
replacement.
●If the replaced fuse blows again, have the
vehicle inspected by your Lexus dealer.
■If there is an overload in a circuit
The fuses are designed to blow, protecting
the wiring harness from damage.
A
B
A
B
A
B
WARNING
■To prevent system breakdowns and
vehicle fire
Observe the following precautions.
Failure to do so may cause damage to
the vehicle, and possibly a fire or injury.
●Never use a fuse of a higher amperage
rating than that indicated, or use any
other object in place of a fuse.
●Always use a genuine Lexus fuse or
equivalent.
Never replace a fuse with a wire, even
as a temporary fix.
●Do not modify the fuses or fuse boxes.
A
B

4187-1. Essential information
7-1.Essential information
Press the switch to flash all of the turn
signal lights.
To turn them off, press the switch once
again.
■Emergency flashers
●If the emergency flashers are used for a
long time while the engine is not running,
the battery may discharge.
●If any of the SRS airbags deploy (inflate)
or in the event of a strong rear impact, the
emergency flashers will turn on automati-
cally.
The emergency flashers will turn off auto-
matically after operating for approxi-
mately 20 minutes. To manually turn the
emergency flashers off, press the switch
twice.
(The emergency flashers may not turn on
automatically depending on the force of
the impact and conditions of the colli-
sion.)
1 Steadily step on the brake pedal
with both feet and firmly depress it.
Do not pump the brake pedal repeatedly
as this will increase the effort required to
slow the vehicle.
2Shift the shift position to N.
If the shift position is shifted to N
3 After slowing down, stop the vehi-
cle in a safe place by the road.
4 Stop the engine.
If the shift position cannot be shifted
to N
3 Keep depressing the brake pedal
with both feet to reduce vehicle
speed as much as possible.
4 To stop the engine, press and hold
the engine switch for 2 consecutive
Emergency flashers
The emergency flashers are used to
warn other drivers when the vehicle
has to be stopped on the road due
to a breakdown, etc.
Operating instructions
If your vehicle has to be
stopped in an emergency
Only in an emergency, such as if it
becomes impossible to stop the
vehicle in the normal way, stop the
vehicle using the following proce-
dure:
Stopping the vehicle

4227-2. Steps to take in an emergency
In the following situations, it is not pos-
sible to be towed by another vehicle
using cables or chains, as the rear
wheels may be locked due to the park-
ing lock. Contact your Lexus dealer or
commercial towing service.
There is a malfunction in the P posi-
tion control system. ( P.177, 436)
 There is a malfunction in the engine
immobilizer system. ( P.64)
 There is a malfunction in the smart
access system with push-button
start. ( P.442)
 The battery is discharged.
( P.444)
WARNING
■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 dam-
aged, broken debris may hit people,
and cause serious damage.
●Make sure to disable all functions of
the vehicle height control of the elec-
tronically modulate d air suspension.
Otherwise, the vehicle height may
change and part of your body may be
caught under the vehicle, possibly
causing injury. (
P.303)
●Do not turn the engine switch off.
This may lead to an accident as the
rear wheels will be locked by the park-
ing lock.
■Installing towing eyelets to the vehi-
cle
Make sure that towing eyelets are
installed securely.
If not securely installed, towing eyelets
may come loose during towing.
NOTICE
■To prevent damage to the vehicle
when towing using a wheel-lift type
truck
●Do not tow the vehicle from the rear
when the engine switch is off. The
steering lock mechanism is not strong
enough to hold the front wheels
straight.
●When raising the vehicle, ensure ade-
quate ground clearance for towing at
the opposite end of the raised vehicle.
Without adequate clearance, the vehi-
cle could be damaged while being
towed.
■To prevent damage to the vehicle
when towing with a sling-type truck
Do not tow with a sling-type truck, either
from the front or rear.
■To prevent damage to the vehicle
during emergency towing
Do not secure cables or chains to the
suspension components.
■Recreational towing (behind motor
home, etc.) (AWD models)
Never dinghy tow your vehicle to pre-
vent causing serious damage to the
AWD system and transmission. ( P.173)
Situations when it is not possible
to be towed by another vehicle

4237-2. Steps to take in an emergency
7
When trouble arises
The following may indicate a problem
with your transmission. Contact your
Lexus dealer or commercial towing
service before towing.
The engine is running but the vehi-
cle does not move.
 The vehicle makes an abnormal
sound.
From the front
Use a towing dolly under the rear
wheels.
From the rear
Use a towing dolly under the front
wheels. When using a flat-bed truck to trans-
port the vehicle, use tire strapping
belts. Refer to the owner’s manual of
the flat-bed truck for the tire strapping
method.
In order to suppress vehicle movement
during transportation, set the parking
brake and turn the engine switch off.
If a tow truck is not available in an
emergency, your vehicle may be tem-
porarily towed using cables or chains
secured to the emergency towing eye-
lets. This should only be attempted on
hard surfaced roads for short distances
at under 18 mph (30 km/h).
A driver must be in the vehicle to steer
and operate the brakes. The vehicle’s
wheels, drive train, axles, steering and
brakes must be in good condition.
To have your vehicle towed by another
Situations when it is necessary to
contact dealers before towing
Towing with a wheel-lift type
truck
NOTICE
■Towing with a sling-type truck
Do not tow with a sling-type truck to pre-
vent body damage.
Using a flatbed truck
Emergency towing
Emergency towing procedure

4247-2. Steps to take in an emergency
vehicle, the towing eyelet must be
installed to your vehicle. Install the tow-
ing eyelet using the following proce-
dure.
1Take out the phillips-head screw-
driver and towing eyelet.
Phillips-head screwdriver
Towing eyelet
2 Remove the eyelet cover using a
flathead screwdriver.
To protect the bodywork, place a rag
between the screwdriver and the vehicle
body as shown in the illustration.
3Insert the towing eyelet into the
hole and tighten partially by hand.
4 Tighten down the towing eyelet
securely using a phillips-head
screwdriver or hard metal bar.
5 Securely attach cables or chains to
the towing eyelet.
Take care not to damage the vehicle body.
6Enter the vehicle being towed and
start the engine.
If the engine does not start, turn the engine
switch to IGNITION ON mode.
7Shift the shift position to N and
release the parking brake.
Turn automatic mode off. ( P.187)
■While towing
If the engine is not running, the power assist
for the brakes and steering will not function,
making steering and braking more difficult.
■Wheel nut wrench
Wheel nut wrench can be purchased at
your Lexus dealer.
A
B

4337-2. Steps to take in an emergency
7
When trouble arises
■Parking brake indicator (warning buzzer)
■Brake hold operated indicator (warning buzzer)
■Warning buzzer
In some cases, the bu zzer may not be heard
due to being in a noisy location or audio
sound.
■Front passenger detection sensor, seat
belt reminder and warning buzzer
●If luggage is placed on the front passen-
ger seat, the front passenger detection
sensor may cause th e warning light to
flash and the warning buzzer to sound
even if a passenger is not sitting in the
seat.
●If a cushion is placed on the seat, the sen-
sor may not detect a passenger, and the
warning light may not operate properly.
■SRS warning light
This warning light system monitors the air-
bag sensor assembly, Pop Up Hood com-
puter assembly, front impact sensors, side
impact sensors (front door), side impact
sensors (front), side impact sensors (rear),
driver’s seat position sensor, driver’s seat
belt buckle switch, front passenger occu-
pant classification system (ECU and sen-
sors), rear seat belt buckle switches (if
equipped), “AIR BAG ON” indicator light, “AIR BAG OFF” indicator light, front pas-
senger’s seat belt buckle switch, seat belt
pretensioners, airbags, interconnecting wir-
ing and power sources. (
P.29)
■If the malfunction indicator lamp comes
on while driving
First check the following:
●Is the fuel tank empty?
If it is, fill the fuel 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 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 steering system warning
light may come on and the warning buzzer
may sound.
Warning lightDetails/Actions
(flashes) (U.S.A.)
or
(flashes)
(Canada)
Indicates a malfunction in the parking brake system
 Have the vehicle inspected by your Lexus dealer immediately.
Warning lightDetails/Actions
(flashes)
Indicates a malfunction in the brake hold system
Have the vehicle inspected by your Lexus dealer immediately.

4477-2. Steps to take in an emergency
7
When trouble arises
8Open and close any of the doors of
your vehicle with the engine switch
off.
9 Maintain the engine speed of the
second vehicle and start the engine
of your vehicle by turning the
engine switch to IGNITION ON
mode.
10 Once the vehicle’s engine has
started, remove the jumper cables
in the exact reverse order from
which they were connected.
11 Close the exclusive jump starting
terminal cover, and reinstall the fuse
box cover to its original position.
12 Install the service cover. ( P.385)
13 Install the engine cover. ( P.385)
Once the engine starts, have the vehi-
cle inspected at your Lexus dealer as
soon as possible.
■Starting the engine when the battery is
discharged
The engine cannot be started by push-start-
ing.
■To prevent battery discharge
●Turn off the headlights and the audio sys-
tem while the engine is off.
●Turn off any unnecessary electrical com-
ponents when the vehicle is running at a
low speed for an extended period, such
as in heavy traffic.
■When the battery is removed or dis-
charged
●Information stored in the ECU is cleared.
When the battery is depleted, have the
vehicle inspected at your Lexus dealer.
●Some systems may require initialization.
(  P.490)
■When removing the battery terminals
When the battery terminals are removed,
the information stored in the ECU is
cleared. Before removi ng the battery termi-
nals, contact your Lexus dealer.
■Charging the battery
The electricity stored in the battery will dis-
charge gradually even when the vehicle is
not in use, due to natural discharge and the
draining effects of certain electrical appli-
ances. If the vehicle is left for a long time,
the battery may discharge, and the engine
may be unable to start. (The battery
recharges automatically during driving.)
■When recharging or replacing the bat-
tery
●In some cases, it may not be possible to
unlock the doors using the smart access
system with push-button start when the
battery is discharged. Use the wireless
remote control or the mechanical key to
lock or unlock the doors.
●The engine may not start on the first
attempt after the battery has recharged
but will start normally after the second
attempt. This is not a malfunction.
●The engine switch mode is memorized by
the vehicle. When the battery is recon-
nected, the system will return to the
mode it was in before the battery was dis-
charged. Before disconnecting the bat-
tery, turn the engine switch off.
If you are unsure wh at mode the engine
switch was in before the battery dis-
charged, be especially careful when
reconnecting the battery.
■When replacing the battery
●Use a Central Degassing type battery
(European Regulations).
●Use a battery with the same case size as
the previous battery and an equivalent
20 hour rate capacity (20HR) or greater.
• If the sizes differ, the battery cannot be properly secured.
• If the 20 hour rate capacity is low, even if
the time period where the vehicle is not
used is a short time, the battery may dis-
charge and the engine may not be able to
start.