air condition Lexus IS250C 2010 Service Manual

5
When trouble arises
459
5-1. Essential information
10_IS250C/350C_U
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably needs
adjustment or repair. Contact your Lexus dealer as soon as possible.
■Visible symptoms
●Fluid leaks under the vehicle
(Water dripping from the air conditioning after use is normal.)
● Flat-looking tires or uneven tire wear
● Engine coolant temperature gauge needle continually points
higher than normal
■ Audible symptoms
●Changes in exhaust sound
● Excessive tire squeal when cornering
● Strange noises related to the suspension system
● Pinging or other noises related to the engine
■ Operational symptoms
●Engine missing, stumbling or running rough
● Appreciable loss of power
● Vehicle pulls heavily to one side when braking
● Vehicle pulls heavily to one side when driving on a level road
● Loss of brake effectiveness, sp ongy feeling, pedal almost touches
the floor

468
5-2. Steps to take in an emergency
10_IS250C/350C_U
■The tire pressure warning light may turn on due to natural causes
The tire pressure warning light may turn on due to natural causes such as natural air
leaks or tire inflation pressure changes caused by temperature. In this case, adjust-
ing the tire inflation pressure will turn off the warning light (after a few minutes).
■When a tires is replaced with a spare tire (vehicles with a spare tire)
The compact spare tire is not equipped with the tire pressure warning valve and
transmitter. If a tire goes flat, the tire pressure warning light will not turn off even
though the flat tire is replaced with the spare tire. Replace the spare tire with the
repaired tire and adjust the proper tire inflation pressure. The tire pressure warning
light will turn off after a few minutes.
■If the tire pressure warning system is inoperative
The tire pressure warning system will be disabled in the following conditions:
(When the condition becomes normal, the system will work properly.)
●If tires not equipped with tire pressure warning valves and transmitters are used
●If the ID code on the tire pressure warning valves and transmitters is not regis-
tered in the tire pressure warning computer
●If a different set of tires has been selected using the satellite switch.
●If the tire inflation pressure is 73 psi (500 kPa, 5.1 kgf/cm2 or bar) or higher
The tire pressure warning system may be disabled in the following conditions:
(When the condition becomes normal, the system will work properly.)
●If electronic devices or facilities using similar radio wave frequencies are nearby
●If a radio set at similar frequencies is in use in the vehicle
●If there is a lot of snow or ice on the vehicle, in particular around the wheels or
wheel housings
●If non-genuine Lexus wheels are used (Even if you use Lexus wheels, the tire
pressure warning system may not work properly with some types of tires.)
●If tire chains are used
■If the tire pressure warning light comes on after blinking for 1 minute frequently
If the tire pressure warning light comes on after blinking for 1 minute frequently
when the “ENGINE START STOP” switch is turned to IGNITION ON mode, have
it checked by your Lexus dealer.

5
When trouble arises
509
5-2. Steps to take in an emergency
10_IS250C/350C_U
If your vehicle overheats
If your engine overheats:
Stop the vehicle in a safe place and turn off the automatic air
conditioning system.
Check to see if steam is coming out from under the hood.
If you see steam: Stop the engine. Carefully lift the hood after the steam sub-
sides and then restart the engine.
If you do not see steam: Leave the engine running and carefully lift the hood.
Remove the engine compartment cover. ( →P. 394)
Check to see if the cooling fan is operating.
If the fan is operating: Wait until the temperature of the engine (shown on the
instrument cluster) begins to fall and then stop the engine.
If the fan is not operating: Stop the engine immediately and call your local Lexus
dealer.
After the engine has cooled
down sufficiently, check the
engine coolant level and inspect
the radiator core (radiator) for
any leaks.STEP1
STEP2
STEP3
STEP4
STEP5

550
6-1. Specifications
10_IS250C/350C_U■
Temperature A, B, C
The temperature grades are A (the highest), B, and C, representing
the tire's resistance to the generation of heat and its ability to dissipate
heat when tested under controlled conditions on a specified indoor
laboratory test wheel.
Sustained high temperature can cause the material of the tire to degenerate
and reduce tire life, and excessive temperature can lead to sudden tire fail-
ure.
The grade C corresponds to a level of performance which all passenger car
tires must meet under the Federal Motor Vehicle Safety Standard No. 139.
Grades B and A represent higher levels of performance on the laboratory
test wheel than the minimum required by law.
Warning: The temperature grades for this tire are established for a tire that
is properly inflated and not overloaded.
Excessive speed, underinflation, or excessive loading, either separately or in
combination, can cause heat buildup and possible tire failure.
Glossary of tire terminology
Tire related termMeaning
Accessory weight
The combined weight (in excess of those standard
items which may be replaced) of automatic transmis-
sion, power steering, power brakes, power windows,
power seats, radio and heater, to the extent that these
items are available as factory-installed equipment
(whether installed or not)
Cold tire inflation pres-
sureTire pressure when the vehicle has been parked for
three hours or more, or has not been driven more
than 1 mile or 1.5 km under that condition
Curb weight
The weight of a motor vehicle with standard equip-
ment, including the maximum capacity of fuel, oil and
coolant, and if so equipped, air conditioning and
additional weight optional engine

572
10_IS250C/350C_U
Alphabetical index
Alphabetical index
A/C ............................................................230
ABS.............................................................204
AFS ...............................................................174
Adaptive front lighting system ..........174
Air conditioning filter .......................... 422
Air conditioning systemAir conditioning filter ....................... 422
Automatic air conditioning system .................................................. 230
Airbags
Airbag operating conditions..........102
Airbag precautions for your child........................................................ 106
Airbag warning light ........................ 464
Front passenger occupant classification system........................... 111
General airbag pr ecautions ......... 106
Locations of airbags.......................... 100
Modification and disposal of airbags .................................................... 110
Proper driving posture ........... 98, 106
Side airbag operating conditions............................................ 103
Side airbag precautions .................. 106
SRS airbags ........................................... 100
Alarm ............................................................95
Antenna .................................................... 247
Anti-lock brake system ......................204
Ashtrays ....................................................352
Audio input ..............................................284 Audio system
Antenna................................................... 247
AUX adapter ...................................... 284
Bluetooth
® audio ............................. 289
CD player/changer ......................... 250
iPod
® player ....................................... 265
MP3/WMA disc................................257
Optimal use ......................................... 282
Portable music player ..................... 284
Radio ........................................................ 242
Steering wheel audio switch........ 286
USB memory player ........................ 273
Automatic air conditioning system .................................................... 230
Automatic headlight leveling system ......................................................175
Automatic light control system......... 173
Automatic transmission Automatic transmission ................... 147
If the shift lever cannot be shifted from P................................... 499
S mode ....................................................... 151
AUX adapter ......................................... 284
A