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5
When trouble arises
533
5-2. Steps to take in an emergency
IS250C/350C_U
■Avoiding a discharged battery
●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, etc.
■Charging the battery
The electricity stored in the battery will discharge gradually even when the vehi-
cle is not in use, due to natural discharge and the draining effects of certain
electrical appliances. If the vehicle is left for a long time, the battery may dis-
charge, and the engine may be unable to start. (The battery recharges automat-
ically during driving.)
■When the battery is removed or discharged
Make sure that the key is not inside the vehicle when recharging or replacing the
battery. The key may be locked in the vehicle if the alarm is activated. (→P. 1 0 1 )
Maintain the engine speed of the second vehicle and turn the
“ENGINE START STOP” switch to IGNITION ON mode,
then start the vehicle’s engine.
Once the vehicle’s engine has started, remove the jumper
cables in the exact reverse order in which they were con-
nected.
Once the engine starts, have the vehicle checked at your Lexus dealer
as soon as possible.STEP5
STEP6
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560
6-1. Specifications
IS250C/350C_U
Ignition system
Electrical system
Spark plug
Make
GapDENSO FK20HBR11
0.043 in. (1.1 mm)
NOTICE
■Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust gap when tuning engine.
Battery
Open voltage* at
68 °F (20 °C):12.6 12.8 V Fully charged
12.2
12.4 V Half charged
11.8
12.0 V Discharged
(*: Voltage checked 20 minutes after
the engine and all the lights are turned
off)
Charging rates5 A max.
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621
Alphabetical index
IS250C/350C_U
Warning buzzersBrake system ......................................... 491
Open door .......................................... 493
Seat belt reminder ............................ 493
Warning lights Anti-lock brake system .................. 492
Brake assist system .......................... 492
Brake system ......................................... 491
Charging system ................................. 491
Electric power steering system
warning light ..................................... 492
Low fuel level....................................... 493
Malfunction indicator lamp .......... 492
Master warning light ........................ 493
Open door ........................................... 493
Pre-collision system ......................... 492
Pretensioners ...................................... 492
Seat belt reminder light .................. 493
SRS airbags .......................................... 492
Tire pressure warning
light........................................................ 493
Warning messages
Dynamic radar cruise control ........................501, 503
Engine oil level ....................................503
Engine oil maintenance..................503
Engine oil pressure.......................... 500
Hood .......................................................503
Intuitive parking assist ..........501, 503
Open door ...........................................503
Parking brake ......................................503
Pre-collision system ..............501, 503
Retractable hardtop ..............501, 503 Smart access system with
push-button start ............................. 510
Steering lock.......................................... 501
Trunk ....................................................... 503
Washer fluid ........................................ 503
Washer
Checking .............................................. 430
Preparing and checking before winter ....................................233
Switch........................................................ 182
Washing and waxing ........................... 396
Weight Cargo capacity ................................... 229
Load limits ............................................. 232
Weight.....................................................552
Wheels ...................................................... 445
Window glasses ...................................... 82
Window lock switch ...............................83
Windows Power windows ..................................... 82
Rear window defogger.................... 251
Washer .................................................... 182
Windshield wiper de-icer.................. 252
Windshield wipers................................. 182
Wireless remote control key Replacing the battery.......................449
WMA disc* ...............................................271W
*: For vehicles with a navigation system, refer to the “Navigation System Owner’s Manual”.
Page 624 of 626
623
What to do if...
IS250C/350C_U
A warning light or indicator
light comes onP. 4 9 1If a warning light turns on or a warning
buzzer sounds...
■Warning lights
or or
P. 4 9 1P. 4 9 2
P. 4 9 3
or
P. 4 9 2P. 4 9 3
P. 4 9 3P. 4 9 3
P. 4 9 2P. 4 9 2
P. 4 9 3P. 4 9 2
P. 4 9 1P. 4 9 3
P. 4 9 2
Brake system warning lightMalfunction indicator lamp
“ABS” warning lightDriver’s seat belt reminder
light
Front passenger’s seat belt
reminder light
Low fuel level warning lightMaster warning light
SRS warning lightElectric power steering system
warning light
Open door warning lightPre-collision system warn-
ing light
Charging system warning
lightTire pressure warning light
Slip indicator