2021 LEXUS LS500 key battery

4427-2. Steps to take in an emergency
■When the electronic key does not work
properly
●Make sure that the smart access system
with push-button start has not been dis-
abled at your Lexus dealer. If it has been
disabled, re-enable it.
●Check if battery-saving mode is set. If it is
set, cancel the function. (P.115)
■Unlocking the door
Use the mechanical key ( P.100) in
order to perform the following opera-
tions: 1
Pull the driver’s door handle and
insert the mechanical key.
2 Unlock the door.
3 Remove the key, return the handle,
and then pull the handle again.
■Locking the door
1 With the door open, push down the
inside lock button.
2 Close the door.
■Trunk
Turn the mechanical key clockwise to
open. ( P.66)
If the electronic key does not
operate properly
If communication between the
electronic key and vehicle is inter-
rupted ( P.115) or the electronic
key cannot be used because the
battery is depleted, the smart
access system with push-button
start and wireless remote control
cannot be used. In such cases, the
doors and trunk can be opened and
the engine can be started by follow-
ing the procedure below.
NOTICE
■In case of a smart access system with
push-button start malfunction or
other key-related problems
Take your vehicle with all the electronic
keys provided with your vehicle to your
Lexus dealer.
Locking and unlocking the
doors, unlocking the trunk

4437-2. Steps to take in an emergency
7
When trouble arises
■Key linked functions
1 Closes the windows and the moon
roof
* or panoramic moon roof* (turn
and hold)
2 Opens the windows and the moon
roof
* or panoramic moon roof* (turn
and hold)
These settings must be customized at your
Lexus dealer.
*:If equipped
1 Depress the brake pedal.
2 Touch the Lexus emblem side of the
electronic key to the engine switch.
When the electronic key is detected, a
buzzer sounds and the engine switch will
turn to IGNITION ON mode.
When the smart access system with
push-button start is deactivated in custom-
ization setting, the engine switch will turn
to ACCESSORY mode.
3 Firmly depress the brake pedal and
check that is shown on the
multi-information display.
4 Press the engine switch.
In the event that the engine still cannot
be started, contact your Lexus dealer.
■Stopping the engine
Set the parking brake, shift the shift position
to P and press the engine switch as you nor-
mally do when stopping the engine.
■Electronic key battery
As the above procedure is a temporary
measure, it is recommended that the elec-
tronic key battery be replaced immediately
when the battery is depleted. ( P.410)
■Alarm (for Canada)
If a door or trunk is unlocked using the
mechanical key when the alarm system is
set, the alarm may be triggered. ( P.66)
WARNING
■When using the mechanical key and
operating the power windows or the
moon roof or panoramic moon roof
Operate the power window or the moon
roof or panoramic moon roof after
checking to make sure that there is no
possibility of any passe nger having any of
their body parts caught in the window or
the moon roof or panoramic moon roof.
Also, do not allow ch ildren to operate the
mechanical key. It is possible for children
and other passengers to get caught in
the power window or the moon roof or
panoramic moon roof.
Starting the engine

4447-2. Steps to take in an emergency
■Changing engine switch modes
Release the brake pedal and press the
engine switch in step 3 above. The engine
does not start and modes will be changed
each time the switch is pressed. ( P.177)
If you have a set of jumper (or booster)
cables and a second vehicle with a
12-volt battery, you can jump start your
vehicle by following the steps below.
Method connecting jumper (or
booster) cables to the battery
1 Confirm that the electronic key is
being carried.
When connecting the jumper (or booster)
cables, depending on the situation, the
alarm may activate and doors locked.
( P.67)
2 Open the trunk lid and remove the
luggage mat. ( P.349)
In the event that the trunk opener cannot
be used, use the mechanical key to open
the trunk. (P.442)
If the vehicle battery is dis-
charged
The following procedures may be
used to start the engine if the vehi-
cle’s battery is discharged.
You can also call your Lexus dealer
or a qualified repair shop.
Restarting the engine

4457-2. Steps to take in an emergency
7
When trouble arises
3Connect a positive jumper cable clamp to on your vehicle and connect the
clamp on the other end of the positive cab le to on the second vehicle. Then,
connect a negative cable clamp to on the second vehicle and connect the
clamp at the other end of the negative cable to .
Positive (+) battery terminal (your vehicle)
Positive (+) battery terminal (second vehicle)
Negative (-) battery terminal (second vehicle)
Negative (-) battery terminal (your vehicle)
4 Start the engine of the second vehi-
cle. Increase the engine speed
slightly and maintain at that level for
approximately 5 minutes to
recharge the battery of your vehi-
cle.
5 Open and close any of the doors of
your vehicle with the engine switch
off.
6 Maintain the engine speed of the
second vehicle and start the engine
of your vehicle by turning the
engine switch to IGNITION ON
mode.
7 Once the vehicle’s engine has
started, remove the jumper cables
in the exact reverse order from
which they were connected.
Method connecting jumper (or
booster) cables to the exclusive
jump starting terminal
1 Confirm that the electronic key is
being carried.
When connecting the jumper (or booster)
cables, depending on the situation, the
alarm may activate and doors locked.
( P.67)
2 Open the hood. Remove the ser-
vice cover. ( P.381, 385)
3 Open the fuse box cover.
A
B
C
D
A
B
C
D

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.

504What to do if... (Troubleshooting)
1-1.What to do if... (Troubleshooting)What to do if... (Troubleshooting)
If you lose your mechanical keys,
new genuine mechanical keys can
be made by your Lexus dealer.
( P.441)
 If you lose your electronic keys, the
risk of vehicle theft increases signifi-
cantly. Contact your Lexus dealer
immediately. ( P.441)
 Is the electronic key battery weak or
depleted? ( P.410)
 Is the engine switch in IGNITION
ON mode?
When locking the doors, turn the engine
switch off. ( P.177)
 Is the electronic key left inside the
vehicle?
When locking the doors, make sure that
you have the electronic key on your per-
son.
The function may not operate prop-
erly due to the condition of the radio
wave. ( P.115)
 Is the child-protector lock set?
The rear door cannot be opened from
inside the vehicle when the lock is set.
Open the rear door from outside and then
unlock the child-protector lock. ( P.105)
 The function to prevent the elec-
tronic key from being left inside the
trunk will operate and you can open
the trunk as usual. Take the key out
from the trunk. ( P.111)
 Did you press the engine switch
while firmly depressing the brake
pedal? ( P.174)
 Is the electronic key anywhere
detectable inside the vehicle?
( P.114)
 Is the steering wheel unlocked?
( P.174)
 Is the electronic key battery weak or
depleted?
If you have a problem, check the
following before contacting your
Lexus dealer.
The doors cannot be locked,
unlocked, opened or closed
You lose your keys
The electronic key does not
operate properly
The doors cannot be locked or
unlocked
The rear door cannot be opened
The trunk lid is closed with the
electronic key left inside
If you think something is wrong
The engine does not start

508Alphabetical Index
Parking brake ............................................... 186
Warning light ............................................... 427
Brake assist .................................................... 304
Break-in tips.....................................................165
Brightness control Instrument panel light control ......... 77, 81
BSM (Blind Spot Monitor)....................... 264
Buzzer Hands off steering wheel warning (LTA)......................................................................... 249
C
Card key ............................................................ 98
Care Exterior ...........................................................368
Interior ............................................................... 371
Seat belts.......................................................... 371
Wheels and wheel ornaments............368
Cargo capacity............................................... 172
Cargo net ....................................................... 349
Center Display ...............................................316
Chains ............................................................... 310
Child restraint system Fixed with a LATCH system .................. 53
Fixed with a seat belt...................................50
Front passenger occupant classification system ............................................................. 40
Points to remember .................................... 45
Riding with children ..................................... 45
Types of child restraint system installation method ........................................................... 46
Using an anchor bracket .......................... 55
Child safety Airbag precautions...................................... 34
Battery precautions ....................... 391, 448
Child restraint system................................. 46
Heated steering wheel and seat heater precautions................................................ 336
How your child should wear the seat belt ............................................................................ 25
Moon roof precautions ............................ 157
Panoramic moon roof precautions ..... 161 Power window lock switch .................... 155
Power window precautions .................. 154
Rear door child-protectors ................... 105
Removed electronic key battery precau-
tions .................................................................. 411
Seat belt extender precautions.............. 25
Seat belt precautions .................................. 45
Trunk precautions....................................... 106
Child-protectors........................................... 105
Cleaning Exterior........................................................... 368
Interior ...............................................................371
Radar sensor ................................... 203, 209
Seat belts ..........................................................371
Wheels and wheel ornaments ........... 368
Clock ................................................75, 78, 354
Clock light ...................................................... 340
Coat hooks..................................................... 353
Coin holder .................................................... 346
Condenser ..................................................... 389
Console box .................................................. 347
Consumption screen .................................... 93
Cooling system.............................................388 Engine overheating...................................449
Cornering lights .............................................192
Cruise control Dynamic radar cruise control with full-speed range ........................... 251, 254
Cup holders ................................................... 346
Current fuel consumption .......................... 84
Curtain shield airbags .................................. 29
Customizable features ...............................476
D
Daytime running light system .................. 190
Defogger Outside rear view mirrors..................... 324
Rear window ................................................ 324
Windshield .................................................... 324
Differential Front differential oil............. ...................... 460
Rear differential oil. ..................................... 461

509Alphabetical Index
Digital Rearview Mirror..............................143
Dimension ...................................................... 456
Dinghy towing................................................. 173
DisplayCenter Display..............................................316
Dynamic radar cruise control with full-speed range ...................................... 254
Head-up display ........................................... 89
Intuitive parking assist...............................272
LTA (Lane Tracing Assist).................... 244
Multi-information display .......................... 82
Parking Support Brake function (rear pedestrians) .............................................. 296
RCD (Rear Camera Detection) ..........281
RCTA .............................................................. 279
Warning message..................................... 436
Distance until next engine oil change76, 81
Do-it-yourself maintenance .................... 375
Door courtesy lights ................................... 340
Door lock Doors.................................................................102
Smart access system with push-button start ................................................................... 113
Wireless remote control......................... 100
Doors Automatic door lock ing and unlocking
system ........................................................... 106
Door closer ................................................... 105
Door glasses ..................................................153
Door lock.........................................................102
Open door warning bu zzer ...... 103, 105
Outside rear view mirrors ....................... 151
Rear door child-protectors ................... 105
Drive distance .................................................. 84
Drive info 1/Drive info 2 .............................. 84
Driver’s seat position memory Driving position memory.........................133
Memory recall function ............................135
Power easy access system .....................133
Drive-Start Control (DSC) .......................170
Driving Break-in tips .................................................. 165 Correct driving posture ............................ 23
Driving mode select switch ..................299
Procedures .................................................... 164
Winter drive tips ........................................ 309
Driving information display ........................ 84
Driving position memory............................133 Memory recall function............................ 135
Power easy access system .................... 133
Driving range ................................................... 84
Driving support system information display ............................................................................. 87
DRS (Dynamic Rear Steering) .............. 304
DSC (Drive-Start Control) .......................170
Dynamic radar cruise control with full-speed range .............................. 251, 254Warning message .....................................263
Dynamic Rear Steering (DRS) .............. 304
E
ECB (Electronically Controlled Brake Sys-
tem) ................................................................ 304
Eco Driving Indicator............................85, 93
Eco Driving Indicator Light ........................ 85
EDR (Event data recorder) ........................... 8
Elapsed time ..................................................... 84
Electric Power Steering (EPS) .............. 304 Warning light .............................................. 430
Electronic key .................................................. 98 Battery-saving function.............................. 114
If the electronic key does not operate properly ....................................................... 442
Replacing the battery ................................ 410
Electronic roof sunshade Jam protection function ........................... 160
Operation ....................................................... 158
Electronically Controlled Brake System (ECB) ............................................................ 304
Electronically modulated air suspension ........................................................................... 301
Emergency flashers ..................................... 418
Emergency, in case of If a warning buzzer sounds................... 427