2019 LEXUS UX250H key battery

4087-2. Steps to take in an emergency
■Starting the hybrid system when the 12-
volt battery is discharged
The hybrid system cannot be started by
push-starting.
■To prevent 12-volt battery discharge
●Turn off the headlight s, the air condition-
ing system, the audio system, etc. while
the hybrid system 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.
■Charging the 12-volt battery
The electricity stored in the 12-volt battery
will discharge gradua lly even when the
vehicle is not in use, due to natural dis-
charge and the draining effects of certain
electrical appliances. If the vehicle is left for
a long time, the 12-volt battery may dis-
charge, and the hybrid system may be
unable to start. (The 12-volt battery
recharges automatically while the hybrid
system is operating.)
■When the 12-volt battery is removed or
discharged
●Information stored in the ECU is cleared.
When the 12-volt battery is depleted,
have the vehicle inspected at your Lexus
dealer.
●In some cases, it may not be possible to
unlock the doors using the smart access
system with push-button start when the
12-volt battery is discharged. Use the
wireless remote control or the mechani-
cal key to lock or unlock the doors.
●The hybrid system may not start on the
first attempt after the 12-volt battery has
recharged but will start normally after the
second attempt. This is not a malfunction.
●The power switch mode is memorized by
the vehicle. When the 12-volt battery is
reconnected, the system will return to the
mode it was in before the 12-volt battery
was discharged. Before disconnecting
the 12-volt battery, turn the power switch
off.
If you are unsure what mode the power
switch was in before the 12-volt battery discharged, be especially careful when
reconnecting the 12-volt battery.
●The power back door must be initialized.
(
 P.119)
■When replacing the 12-volt battery
●Use a Central Degassing type 12-volt
battery (European Regulations).
●Use a 12-volt battery that the case size is
same as the previous one (LN1), 20 hour
rate capacity (20HR) is equivalent
(45Ah) or greater, and performance rat-
ing (CCA) is equivalent (286A) or
greater.
• If the sizes differ, the 12-volt battery can- not be properly secured.
• If an improper 12-volt battery is used, bat-
tery performance may decrease and the
hybrid system may not be able to restart.
• If the 20 hour rate capacity is low, even if
the time period where the vehicle is not
used is a short time, the 12-volt battery
may discharge and hybrid system may
not be able to start.
●Use a 12-volt battery with a handle. If a
12-volt battery without a handle is used,
removal is more difficult.
●After exchanging, firmly attach the fol-
lowing items to the exhaust hole of the 12-
volt battery.
• Confirm that the elbow is securely attached to the exhaust hose and exhaust
hole.
• Confirm that the exhaust hole plug is securely attached to the exhaust hole that
the elbow is not attached to.
• Use the elbow/exhaust hole plug included with the 12-volt battery
exchanged or the on e installed on the
battery prior to the exchange. (Depend-
ing on the 12-volt battery to be
exchanged, the exhaust hole may be
plugged.)

460What 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.402)
 If you lose your electronic keys, the
risk of vehicle theft increases signifi-
cantly. Contact your Lexus dealer
immediately. ( P.402)
 Is the electronic key battery weak or
depleted? ( P.368)
 Is the power switch in ON?
When locking the doors, turn the
power switch off. ( P.162)
 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 prop-
erly due to the condition of the radio
wave. ( P.125) 
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.111)
 Did you press the power switch
while firmly depressing the brake
pedal? ( P.162)
 Is the shift lever in P? ( P.167)
 Is the electronic key anywhere
detectable inside the vehicle?
( P.124)
 Is the steering wheel unlocked?
( P.163)
 Is the electronic key battery weak or
depleted?
In this case, the hybrid system can
be started in a temporary way.
( P.404)
 Is the 12-volt battery discharged?
( P.405)
 Is the power switch in ON?
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 doors cannot be locked or
unlocked
The rear door cannot be opened
If you think something is wrong
The hybrid system does not start
The shift lever cannot be shifted
from P even if you depress the
brake pedal

464Alphabetical Index
C
Card key .......................................................... 104
CareAluminum wheels ...................................... 322
Exterior ........................................................... 322
Interior ............................................................. 325
Seat belts........................................................ 325
Cargo capacity............................................... 157
Cargo hooks ................................................. 296
Center Display ............................................. 270
Chains .............................................................. 264
Child-protectors...............................................111
Child restraint system................................... 44 Fixed with a LATCH system .................. 52
Fixed with a seat belt................................... 48
Front passenger occupant classification system ............................................................. 39
Points to remember .................................... 44
Riding with children ..................................... 44
Types of child restraint system installation method ........................................................... 46
Using an anchor bracket .......................... 54
Child safety ....................................................... 44 12-volt battery precautions ...... 343, 409
Airbag precautions...................................... 36
Back door precautions...............................112
Child restraint system................................. 44
Heated steering wheel and seat heater precautions................................................286
How your child should wear the seat belt ............................................................................ 28
Moon roof precautions ............................149
Power window lock switch.....................146
Power window precautions ...................146
Rear door child-protectors ....................... 111
Removed key battery precautions ...369
Seat belt extender precautions ............. 28
Seat belt precautions .................................. 52
Cleaning...............................................322, 325 Aluminum wheels ...................................... 322
Exterior ........................................................... 322 Interior .............................................................325
Radar sensor ...................................... 192, 227
Seat belts ........................................................325
Clock .................................................78, 82, 301
Coat hooks...................................................... 310
Compass ........................................................... 317
Condenser ..................................................... 340
Console box .................................................. 294
Consumption screen .....................................97
Coolant Capacity .......................................................... 419
Checking .......................................................339
Preparing and checking before winter..........................................................................263
Cooling system............................................. 339 Hybrid system overheating ................... 410
Cornering lights ............................................. 179 Replacing light bulbs ................................ 374
Cruise control Dynamic radar cruise control with full-
speed range ................................................216
Cup holders ................................................... 294
Current fuel consumption .......................... 89
Curtain shield airbags ....................................31
Customizable features .............................. 434
D
Daytime running light system ................... 177
Deck board .................................................... 297
Deck under tray ........................................... 296
Defogger Outside rear view mirrors..................... 277
Rear window ................................................ 277
Windshield .................................................... 277
Differential ........................................................ 421
Dimension ........................................................416
Dinghy towing.................................................. 161
Display BSM (Blind Spot Monitor).................... 226
Dynamic radar cruise control with full-
speed range ................................................216
Energy monitor .............................................. 97

Alphabetical Index465
Head-up display ........................................... 93
Intuitive parking assist.............................. 232
LTA (Lane-Tracing Assist) .....................210
Multi-information display .......................... 87
RCTA .............................................................. 239
Warning messages ..................................395
Distance until next engine oil change .. 80, 86
Do-it-yourself maintenance .................... 333
Door lock Doors................................................................ 108
Smart access system with push-button start .................................................................. 124
Wireless remote control......................... 106
Doors Automatic door lock ing and unlocking
system ............................................................... 111
Back door..........................................................112
Door glasses ..................................................145
Door lock........................................................ 108
Open door warning bu zzer .......... 109, 111
Outside rear view mirrors ...................... 142
Rear door child-protectors ....................... 111
Side doors ...................................................... 108
Drive distance .................................................. 89
Drive info 1/Drive info 2 .............................. 89
Driver’s seat position memory .................133
Drive-start control ........................................152
Driving................................................................152 Break-in tips ...................................................153
Correct driving posture ............................ 25
Driving mode select switch .................. 255
Hybrid vehicle driving tips ...................... 261
Procedures .....................................................152
Winter drive tips......................................... 263
Driving information display ........................ 88
Driving position memory............................133 Memory recall function ............................135
Driving range ................................................... 89
Driving support system information display ............................................................................. 90
Dynamic radar cruise control with full- speed range..................................................216
Warning message .........................224, 395
E
ECB (Electronically Controlled Brake Sys-
tem) ................................................................ 256
Eco drive mode ............................................ 255
EDR (Event data recorder) ........................... 8
E-Four .............................................................. 257
Elapsed time ..................................................... 89
Electric motor Location ............................................................. 62
Electric Power Steering (EPS) Function .......................................................... 257
Warning light .............................................. 388
Electronically Controlled Brake System (ECB) ............................................................ 256
Electronic key ................................................ 104 Battery-saving function............................ 125
If the electronic key does not operate properly ...................................................... 403
Replacing the battery .............................. 368
Emergency, in case of If a warning buzzer sounds.................. 386
If a warning light turns on...................... 386
If a warning message is displayed .... 395
If the 12-volt battery is discharged ... 405
If the electronic key does not operate properly ...................................................... 403
If the fuel filler do or cannot be opened
..........................................................................402
If the hybrid system will not start ....... 400
If the vehicle is trapped in rising water .......................................................................... 379
If you have a flat tire ................................. 399
If you lose your keys .................................402
If you think something is wrong......... 385
If your vehicle becomes stuck ...............413
If your vehicle has to be stopped in an emergency .................................................378
If your vehicle needs to be towed ...... 381
If your vehicle overheats ......................... 410

468Alphabetical Index
J
JackPositioning a floor jack............................ 336
Jam protection function Moon roof ...................................................... 148
Power back door opener and closer. 119
Power windows............................................145
K
Keyless entrySmart access system with push-button start .................................................................. 124
Wireless remote control......................... 106
Keys.................................................................... 104 Battery-saving function ............................125
Electronic key ............................................... 104
If the electronic key does not operate properly.......................................................403
If you lose your keys................................. 402
Key number plate ....................................... 104
Keyless entry .............................. 108, 113, 124
Mechanical key............................................ 104
Power switch ................................................. 162
Replacing the battery...............................368
Warning buzzer ........................................... 124
Wireless remote control key ................ 106
Knee airbags ...................................................... 31
L
Lane Tracing Assist (LTA) ....................... 205 Operation......................................................205
Warning messages .................................... 213
Language (multi-informa tion display) ..... 91
LATCH anchors ............................................. 52
Lever Auxiliary catch lever .................................335
Hood lock release lever.........................335
Shift lever.......................................................... 167
Turn signal lever .............................................171
Wiper lever......................................... 184, 188 Lexus climate concierge ...........................274
Lexus Enform Safety Connect.................. 56
Lexus Safety System+2.0 ..........................192
Automatic High Beam ............................. 180
Dynamic radar cruise control with full-
speed range ................................................216
LTA (Lane Tracing Assist) ................... 205
PCS (Pre-Collision System) ................. 198
RSA (Road Sign Assist)............................214
License plate lights Light switch ..................................................... 177
Replacing light bulbs ................................ 374
Light bulbs Replacing ....................................................... 374
Wattage .......................................................... 422
Lights Automatic High Beam system .............180
Cornering lights ...........................................179
Fog light switch ............................................ 183
Front interior lights ......................................291
Headlight switch........................................... 177
Illuminated entry system ........................ 290
Interior light list ........................................... 290
Luggage compartment light ................... 114
Personal lights ............................................. 292
Rear interior lights .......................................291
Replacing light bulbs ................................ 374
Turn signal lever ............................................ 171
Vanity lights ................................................... 301
Wattage .......................................................... 422
Welcome light illumination control ... 178
Lock steering column ..................................163
LTA (Lane Tracing Assist) ....................... 205 Operation ..................................................... 205
Warning messages.....................................213
Luggage cover ............................................. 298
M
Maintenance Do-it-yourself maintenance .................333
General maintenance .............................329
Maintenance data ....................................... 416

470Alphabetical Index
Parking brake engaged warning buzzer........................................................................... 174
Warning light ...............................................389
Warning message....................................... 174
Parking lights Light switch ..................................................... 177
Replacing light bulbs................................ 374
Parking Support Brake function (rear- crossing vehicles) .......................... 243, 252Function .......................................................... 252
Parking Support Brake function (static objects) .............................................. 243, 247Function .......................................................... 247
PCS (Pre-Collision System) .................... 198 Function ........................................................... 198
PCS OFF switch ........................................200
Warning light ............................................... 392
Personal lights............................................... 290
PKSA (Parking Support Alert) ................231
PKSB (Parking Support Brake)............. 243 Warning message..................................... 246
Power back door open er and closer ..... 115
Power control unit coolant ...................... 339 Capacity ...........................................................419
Checking ....................................................... 339
Preparing and checking before winter......................................................................... 263
Power easy access system ........................133
Power outlets ................................................ 302
Power steering (Electric Power Steering system).......................................................... 257Warning light .............................................. 388
Power switch ................................................... 162 Auto power off function ...........................164
Changing the power switch modes ..164
If your vehicle has to be stopped in an
emergency ................................................ 378
Starting the hybrid system....................... 162
Power windows ..............................................145 Door lock linked window operation..146
Jam protection function............................145
Operation........................................................145 Window lock switch.................................. 146
Pre-Collision System (PCS) .................... 198 Function ........................................................... 198
PCS OFF switch ....................................... 200
Warning light ...............................................392
R
Radar cruise control (dynamic radar cruise control with full-speed range)...............216
Radiator ........................................................... 340
RCTA (Rear Cross Traffic Alert) 231, 239
RCTA Function ..........................................................239
Warning message .....................................240
Rear Cross Traffic Alert (RCTA) 231, 239
Rear seat Folding down the rear seatbacks ........132
Rear side marker lights Light switch ..................................................... 177
Rear turn signal lights Replacing light bulbs ................................ 374
Turn signal lever ............................................ 171
Rear view mirror Inside rear view mirror ............................. 140
Outside rear view mirrors.......................142
Rear window defogger ..............................277
Rear window wiper...................................... 188
Refueling .......................................................... 190 Capacity ...........................................................417
Fuel types .........................................................417
Opening the fuel tank cap ..................... 190
When the fuel filler door cannot be
opened.........................................................402
Regenerative braking ................................... 63
Remote Touch .............................................. 270
Replacing Electronic key battery ............................. 368
Fuses.................................................................370
Light bulbs ..................................................... 374
Tires ................................................................. 355
Resetting the message indicating mainte- nance is required ...................................... 328

474Alphabetical Index
Engine ............................................................. 387
High coolant temperature .................... 387
Hybrid system overheat......................... 392
Hybrid system ............................................. 387
Intuitive parking assist................. 238, 389
Low engine oil pressure.........................386
LTA (Lane Tracing Assist)......... 205, 391
Open door.............................................. 109, 111
Open hood........................................................ 111
Open window ...............................................146
PKSA (Parking Support Alert) ............. 231
PKSB (Parking Support Brake) .........390
Pre-collision braking................................. 198
RCTA (Rear Cross Traffic Alert) ......389
Seat belt ............................................... 390, 391
Warning lights............................................... 386 ABS ................................................................. 388
Brake hold operated indicator ...........389
Brake Override System ...........................391
Brake system ...............................................386
Charging system .......................................386
Drive-Start Control ....................................391
Electric power steering ......................... 388
High coolant temperature .................... 387
Intuitive parking assist OFF indicator.........................................................................389
Low engine oil pressure.........................386
Low fuel level ...............................................390
LTA indicator .................................................391
Malfunction indicator lamp................... 387
Parking brake indicator ..........................389
PKSB OFF indicator ................................390
Pre-collision system ................................. 392
RCTA OFF indicator...............................389
Seat belt reminder light ............... 390, 391
Slip indicator ............................................... 388
SRS................................................................... 388
Tire pressure ................................................ 387
Warning messages ..................................... 395
Washer Checking ......................................................... 341
Preparing and checking before winter ..........................................................................263
Switch..................................................... 184, 188
Washing and waxing.................................. 322
Weights Cargo capacity .............................................157
Load limits ...................................................... 160
Weights ........................................................... 416
Wheels ............................................................. 363 Size .................................................................... 422
Window glasses .............................................145
Window lock switch .....................................146
Windows Power windows ........................................... 145
Rear window defogger........................... 277
Washer ................................................. 184, 188
Windshield wiper de-icer ..........................281
Windshield wipers Intermittent windshield wipers ............. 184
Position............................................................. 186
Rain-sensing windshield wipers .......... 184
Winter driving tips....................................... 263
Wireless remote control key ................... 106 Battery-saving function............................ 125
Locking/Unlocking ................................... 106
Panic mode .................................................... 106
Replacing the battery .............................. 368
For information regarding the equipment listed below, refer to
the “NAVIGATION AND MULTI-
MEDIA SYSTEM OWNER’S
MANUAL”.
· Audio/video system
· Navigation system
· Lexus parking assist monitor
· Lexus Enform