ECU LEXUS LS500 2021 Repair Manual

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.

4497-2. Steps to take in an emergency
7
When trouble arises
1Stop the vehicle in a safe place and
turn off the air conditioning system,
and then stop the engine.
2 If you see steam:
Carefully lift the hood after the
steam subsides.
If you do not see steam:
Carefully lift the hood.
3 After the engine has cooled down
sufficiently, inspect the hoses and
WARNING
■After recharging the battery
Have the battery inspected at your Lexus
dealer as soon as possible.
If the battery is dete riorating, continued
use may cause the battery to emit a mal-
odorous gas, which may be detrimental
to the health of passengers.
■When replacing the battery
●When the vent plug and indicator are
close to the hold down clamp, the bat-
tery fluid (sulfuric acid) may leak.
●For information regarding battery
replacement, contact your Lexus
dealer.
●After replacing, securely attach the
exhaust hose and exhaust hole plug to
the exhaust hole of the replaced bat-
tery. If not properly installed, gases
(hydrogen) may leak into the vehicle
interior, and there is the possible dan-
ger of the gas igniting and exploding.
NOTICE
■When handling jumper cables
When connecting the jumper cables,
ensure that they do not become entan-
gled in the cooling fan or engine drive
belt.
■To prevent damaging the vehicle
The exclusive jump starting terminal is to
be used when charging the battery from
another vehicle in an emergency. It can-
not be used to jump start another vehicle.
If your vehicle overheats
The following may indicate that
your vehicle is overheating.
 The engine coolant temperature
gauge ( P.75, 78) is in the red
zone or a loss of engine power is
experienced. (For example, the
vehicle speed does not increase.)
 “Engine Coolant Temp High Stop
in a Safe Place See Owner’s
Manual” is shown on the
multi-information display.
 Steam comes out from under the
hood.
Correction procedures

4758-1. Specifications
8
Vehicle specifications
*: Table 1 -Occupant loading and distribution for vehicle normal load for various desig-nated seating capacities
Treadwear indicators (TWI)
The projections within the principal grooves
designed to give a visual indication of the degrees
of wear of the tread
Wheel-holding fixtureThe fixture used to hold the wheel and tire assembly
securely during testing
Tire related termMeaning
Designated seating capac- ity, Number of occupantsVehicle normal load, Num- ber of occupantsOccupant distribution in a normally loaded vehicle
2 through 422 in front
5 through 1032 in front, 1 in second seat
11 through 1552 in front, 1 in second seat, 1 in third seat, 1 in fourth seat
16 through 2072 in front, 2 in second seat, 2 in third seat, 1 in fourth seat

4808-2. Customization
■Smart access system with push-button start and wireless remote control
( P.102, 113)
■Smart access system with push-button start ( P.102, 113)
■Wireless remote control ( P.100, 102, 106)
FunctionDefault settingCustomized set-
ting
Operating signal (Buzzers)5OffO——O1 to 7
Operation signal (Emer-
gency flashers)OnOffO——O
Time elapsed before auto-
matic door lock function is
activated if door is not
opened after being unlocked
60 seconds
Off
O——O30 seconds
120 seconds
Open door warning buzzerOnOff———O
FunctionDefault settingCustomized set-ting
Smart access system with
push-button startOnOff———O
Smart door unlockingDriver’s doorAll the doorsO——O
Time elapsed before unlock-
ing all the door when gripping
and holding the driver’s door
handle
2 seconds
Off
———O1.5 seconds
2.5 seconds
Number of consecutive door
lock operations2 timesAs many as desired———O
FunctionDefault settingCustomized set- ting
Wireless remote controlOnOff———O
Unlocking operation
Driver’s door
unlocked in one step, all doors
unlocked in two step
All doors
unlocked in one step
O——O
ABCD
ABCD
ABCD

4929-1. For owners
9-1.For owners
Déroulez la sangle diagonale de
telle sorte qu'elle passe bien sur
l'épaule, sans pour autant être en
contact avec le cou ou glisser de
l'épaule.
 Placez la sangle abdominale le plus
bas possible sur les hanches.
 Réglez la position du dossier de
siège. Asseyez-vous le dos droit et
calez-vous bien dans le siège.
 Ne vrillez pas la ceinture de sécu-
rité.
Reporting safety defects for
U.S. owners
If you believe that your vehicle has a
defect which could cause a crash or
could cause injury or death, you
should immediately inform the
National Highway Traffic Safety
Administration (NHTSA) in addition
to notifying the Lexus Division of
Toyota Motor Sales, U.S.A., Inc.
(Toll-free: 1-800-25-LEXUS).
If NHTSA receives similar com-
plaints, it may open an investigation,
and if it finds that a safety defect
exists in a group of vehicles, it may
order a recall and remedy campaign.
However, NHTSA cannot become
involved in individual problems
between you, your dealer, or Lexus
Division of Toyota Motor Sales,
U.S.A., Inc.
To contact NHTSA, you may call the
Vehicle Safety Hotline toll-free at
1-888-327-4236 (TTY:
1-800-424-9153); go to
http://www.safercar.gov ; or write to:
Administrator, NHTSA, 1200 New
Jersey Ave. SE., Washington, DC
20590. You can also obtain other
information about motor vehicle
safety from
http://www.safercar.gov.
Seat belt instructions for
Canadian owners (in French)
The following is a French explana-
tion of seat belt instructions
extracted from the seat belt section
in this manual.
See the seat belt section for more
detailed seat belt instructions in
English.
Utilisation correcte des cein-
tures de sécurité

4939-1. For owners
9
For owners
■Traitement des ceintures de sécu-
rité
Nettoyez avec un chiffon ou une
éponge humidifiés avec de l'eau savon-
neuse tiède. Vérifiez régulièrement
que les ceintures ne sont pas usées,
effilochées ou entaillées excessive-
ment.
Entretien et soin
AVERTISSEMENT
■Détérioration et usure des ceintures
de sécurité
Inspectez le système de ceintures de
sécurité régulière ment. Contrôlez
l'absence de coupures, d'effilochages et
de pièces desserrées. N'utilisez pas une
ceinture de sécurité endommagée avant
qu'elle ne soit remplacée. Une ceinture
de sécurité endommagée ne permet pas
de protéger un occupant de blessures
graves ou mortelles.

4959-1. For owners
9
For owners
Coussins gonflables rideaux SRS
• Participent principalement à la protection de la tête des occupants des sièges latéraux
• Peut contribuer à empêcher les occupants d’être éjectés du véhicule en cas de tonneau
Coussins gonflables de coussin de siège SRS (sur modèles équip\
és)
Contribue à retenir les occupants des sièges arrière électriques
■Composants du système de coussins gonflables SRS
Système de classification de l'occupant du siège passager avant (ECU et cap-
teurs)
Capteurs d'impact latéral (porte avant)
Coussins gonflables de genoux
Coussin gonflable passager avant
Coussins gonflables rideaux
Témoins indicateurs “AIR BAG ON” et “AIR BAG OFF”
Coussins gonflables latéraux avant
Capteurs d'impact latéral (avant)
Témoin d'avertissement SRS
Coussins gonflables latéraux arrière
Prétensionneurs de ceinture de sécurité
Coussin gonflable conducteur
Coussins gonflables de coussin de siège (sur modèles équipé\
s)
Contacts de boucle de ceinture de sécurité de siège arrière \
(sur modèles
équipés)
E
F
A
B
C
D
E
F
G
H
I
J
K
L
M
N