2020 Lexus IS300 key battery

5748-2. Steps to take in an emergency
IS350 AWD/IS350/IS300 AWD/IS300_U
■Stopping the engine
Shift the shift lever to P and press the engine switch as you normally do when stopping
the engine.
■Replacing the key battery
As the above procedure is a temporary measure, it is recommended that the electronic
key battery be replaced immediately when the battery is depleted. ( P. 502)
■Changing engine switch modes
Release the brake pedal and press the engine switch in step above.
The engine does not start and modes will be changed each time the switch is pressed.
(  P. 187)
■When the electronic key does not work properly
●Make sure that the smart access system wi th push-button start has not been deacti-
vated in the customization setting. If it is off, turn the function on.
(Customizable features:  P. 613)
●Check if battery-saving mode is set. If it is set, cancel the function. ( P. 136)
WARNING
■When using the mechanical key and operating the power windows or moon roof
Operate the power window or moon roof after checking to make sure that there is no
possibility of any passenger having any of their body parts caught in the window or
moon roof.
Also, do not allow children to operate the mechanical key. It is possible for children and
other passengers to get caught in the power window or moon roof.
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5758-2. Steps to take in an emergency
8
When trouble arises
IS350 AWD/IS350/IS300 AWD/IS300_U
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.
Confirm that the electronic key is
being carried.
When connecting the jumper (or
booster) cables, depe nding on the situa-
tion, the alarm may activate and doors
locked. (
P. 79)
Open the hood ( P. 470)
If the vehicle battery is discharged
The following procedures may be used to start the engine if the vehicle’s bat-
tery is discharged.
You can also call your Lexus deal er or a qualified repair shop.
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5778-2. Steps to take in an emergency
8
When trouble arises
IS350 AWD/IS350/IS300 AWD/IS300_U
Maintain the engine speed of the second vehicle and start the engine of your
vehicle by turning the engine switch to IGNITION ON mode.
Once the vehicle’s engine has started, remove the jumper cables in the exact
reverse order from which they were connected.
Once the engine starts, have the vehicle inspected at your Lexus dealer as soon
as possible.
■Starting the engine when the battery is discharged
The engine cannot be started by push-starting.
■To prevent battery discharge
●Turn off the headlights and the audio system while the engine is off.
●Turn off any unnecessary electrical components when the vehicle is running at a low
speed for an extended period , such as in heavy traffic.
■Charging the battery
The electricity stored in the battery will disc harge gradually even when the vehicle is not
in use, due to natural discharge and the draini ng effects of certain electrical appliances. 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 battery
●In some cases, it may not be possible to un lock 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 discharged.
Before disconnecting the battery, turn the engine switch off.
If you are unsure what mode the engine switch was in before the battery discharged, be
especially careful when reconnecting the battery.
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636
IS350 AWD/IS350/IS300 AWD/IS300_UWhat to do if... (Troubleshooting)
What to do if... (Troubleshooting)
●If you lose your mechanical keys, ne
w genuine mechanical keys can be made
by your Lexus dealer. ( P. 120)
●If you lose your electronic keys, the risk of vehicle theft increases significantly.
Contact your Lexus dealer immediately. ( P. 123)
●Is the electronic key battery weak or depleted? ( P. 502)
●Is the engine switch in IGNITION ON mode?
When locking the doors, turn the engine switch off. (P. 187)
●Is the electronic key left inside the vehicle?
When locking the doors, make sure that you have the electronic key on your
person.
●The function may not operate properly du e to the condition of the radio wave.
( P. 137)
●Is the child-protector lock set?
The rear door cannot be opened from in side the vehicle when the lock is set.
Open the rear door from outside and then unlock the child-protector lock.
( P. 127)
If you have a problem, check the foll owing before contacting your Lexus
dealer.
The doors cannot be locked, unlocked, opened or closed
You lose your keys
The doors cannot be locked or unlocked
The rear door cannot be opened

637What to do if... (Troubleshooting)
IS350 AWD/IS350/IS300 AWD/IS300_U
●The function to prevent the electronic 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. 132)
●Did you press the engine switch while firmly depressing the brake pedal?
( P. 186)
●Is the shift lever in P? ( P. 188)
●Is the electronic key anywhere detectable inside the vehicle? ( P. 135)
●Is the steering wheel unlocked? ( P. 188)
●Is the electronic key battery weak or depleted?
In this case, the engine can be started in a temporary way. (P. 573)
●Is the battery discharged? ( P. 575)
●Is the engine switch in IGNITION ON mode?
If you cannot release the shift lever by depressing the brake pedal with the
engine switch in IGNITION ON mode. ( P. 196)
●It is locked automatically to prevent theft of the vehicle. ( P. 188)
The trunk lid is closed with the electronic key left inside
If you think something is wrong
The engine does not start
The shift lever cannot be shifted from
P even if you depress the brake
pedal
The steering wheel cannot be turned after the engine is stopped

643Alphabetical index
IS350 AWD/IS350/IS300 AWD/IS300_U
Child safety ................................................ 52Airbag precautions ..............................38
Battery precautions ............. 483, 578
Child restraint system ......................... 53
How your child should wear the seat belt .......................................... 32
Installing child restraints..................... 57
Moon roof precautions.................... 169
Power window lock switch ............ 162
Power window precautions .......... 165
Rear door child-p rotectors ............ 127
Removed electronic key battery precautions.............. 503
Seat belt extender precautions ........................................... 35
Seat belt precautions ..........................56
Seat heater precautions..................426
Trunk precautions............................... 133
Child-protectors..................................... 127 Cleaning .......................................454, 458
Aluminum wheels ..............................455
Exterior ................................................... 454
Interior .....................................................458
Seat belts................................................ 459
Clock..........................................................437
Coat hooks ............................................... 441
Compass ..................................................449
Condenser.............................................. 480
Console box ............................................432
Cooling system ......................................478 Engine overheating .......................... 579
Cruise control Dynamic radar cruise control ..... 248
Cup holders............................................ 433
Current fuel consumption .................................. 112, 113
Curtain shield airbags ............................36
Customizable features ........................ 613

645Alphabetical index
IS350 AWD/IS350/IS300 AWD/IS300_U
E-mail.........................................................380
Eco drive mode ..................................... 297
Eco Driving Indicator........................... 109
EDR (Event data recorder) ...................10
Elapsed time .............................................. 112
Electric Power Steering (EPS) ....... 302Warning light .......................................526
Electronic key ........................................... 118 Battery-saving function .....................137
If the electronic key does not operate properly............................. 572
Replacing the battery ...................... 502
Emergency, in case of If a warning message is displayed ........................................532
If the electronic key does not operate properly ........ 572
If the engine will not start............... 570
If the vehicle battery is discharged .........................................575
If the vehicle is trapped in rising water ......................................... 516
If the warning buzzer sounds................................................. 525
If the warning light turns on.......... 525
If you have a flat tire ......................... 559
If you think something is wrong...............................................523
If your vehicle becomes stuck ..................................................... 583
If your vehicle has to be stopped in an emergency ........... 515
If your vehicle needs to be towed ........................................ 517
If your vehicle overheats ................579 Emergency flashers .............................. 514
Engine ....................................................... 589
ACCESSORY mode .......................187
Compartment ..................................... 473
Engine switch ....................................... 186
Hood........................................................ 470
How to start the engine................... 186
Identification number...................... 588
If the engine will not start ............... 570
Ignition switch (engine switch) .... 186
Overheating......................................... 579
Engine coolant .......................................478 Capacity................................................. 592
Checking ............................................... 478
Preparing and checking before winter ....................................306
Engine coolant temperature gauge ........................................................ 89
Engine immobilizer system .................. 76
Engine oil ..................................................475 Capacity................................................ 590
Checking ............................................... 475
Preparing and checking before winter ....................................306
Engine oil maintenance data ............ 477
Engine switch ...........................................186
Enhanced VSC .......................................301
EPS (Electronic Power Steering) ........ 302 Warning light ....................................... 526
Event data recorder (EDR)................... 10
E

648Alphabetical index
IS350 AWD/IS350/IS300 AWD/IS300_U
JackPositioning a floor jack ......................471
Vehicle-equipped jack .................. 560
Jack handle ............................................. 560
Jam protection function Moon roof ...............................................167
Power windows ................................... 163
Keyless entry Smart access system with push-button start ......... 124, 130
Wireless remote control ....... 124, 130
Keys............................................................... 118 Battery-saving function .....................137
Electronic key ......................................... 118
Engine switch ........................................ 186
If the electronic key does not operate properly ........ 572
Key number plate ................................. 118
Keyless entry ........................................... 118
Mechanical key ...................................... 119
Replacing the battery ...................... 502
Warning buzzer .................................. 125
Wireless remote control ................... 118
Knee airbags ............................................. 36 Lane Departure Alert with
steering control (LDA) ................... 240
Language (multi-information display)..............103
LATCH anchors ...................................... 58
LDA (Lane Departure Alert with steering control) ...................... 240
Lever Auxiliary catch lever ......................... 470
Hood lock release lever................. 470
Internal trunk release lever ............. 132
Shift lever .................................................. 191
Tilt and telescopic steering lock release lever ............................ 155
Turn signal lever .................................. 198
Wiper lever.............................................210
Lexus Display Audio controller ....... 314
Lexus Display Audio system ............. 312
Lexus Enform
*
Lexus Enform Remote*........................ 74
Lexus Enform Safety Connect ........... 75
Lexus parking assist monitor
*.........269
Lexus Safety System + ........................222 Automatic High Beam....................206
Dynamic radar cruise control ..... 248
LDA (Lane Departure Alert with steering control) ................... 240
PCS (Pre-Collision System) ....... 229
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