cooling Lexus IS300 2003 Basic Functions / LEXUS 2003 IS300 OWNER'S MANUAL (OM53439U)

GAUGES, METERS AND SERVICE REMINDER INDICATORS
41
ENGINE COOLANT TEMPERATUREGAUGE
SV13012

Normal range
The gauge indicates the engine coolant temperature when
the ignition switch is on. The engine operating
temperature will vary with changes in weather and engine
load.
If the needle points to the red zone or higher, stop your vehicle
and allow the engine to cool.
Your vehicle may overheat during severe operating conditions,
such as:
 Driving up a long hill on a hot day.
 Reducing speed or stopping after high speed driving.
 Idling for a long period with the air conditioning on in
stop±and±go traffic.
NOTICE
Do not remove the thermostat in the engine cooling
system as this may cause the engine to overheat. Thethermostat is designed to control the flow of coolantto keep the temperature of the engine within thespecified operating range.
Do not continue driving with an overheated engine.See ºIf your vehicle overheatsº on page 271.
2003 IS300 from Aug. '02 Prod. (OM53439U)

AIR CONDITIONING
183
(a) Climate control
SETTING OPERATION ± automatic control
SV21018
1. Set the air flow control dial and the fan speed control
dial to ºAUTOº positions.
An indicator light will illuminate to show that the automatic
operation mode has been selected.
Air flow quantity and switching of the diffusers are
automatically adjusted.
When one of the manual control dials is turned while operating
in automatic mode, the operation corresponding to the dial
turned is set. Other conditions continue to be adjusted
automatically.
When the fan speed control dial is turned to ºOFFº, the fan is
turned off. If the ºA/Cº button indicator flashes, there is a problem in the
air conditioning system and the air conditioning automatically
shuts off. If this happens, take your vehicle to your Lexus
dealer for service.
SV21021a
2. Turn the temperature control dial to set the desired
temperature.
The temperature control dial is used to set the desired
passenger compartment temperature.
The temperature of air
delivered to the passenger compartment will be controlled
automatically according to the setting. The figures on the
panel indicate degrees Fahrenheit.
When you adjust the temperature control dial to maximum
cooling, the air intake mode will be automatically changed to
RECIRCULATED AIR.
2003 IS300 from Aug. '02 Prod. (OM53439U)

AIR CONDITIONING
184SETTING OPERATION ± manual control
If manual air flow selection is desired ±
SV21017
The outlets from which air is delivered can be selected
manually by pushing the button. The function of each mode is
as follows:
1Panel
± Air flows mainly from the instrument panel vents.
2Bi±level ± Air flows from both the floor vents and the
instrument panel vents.
3Floor ± Air flows mainly from the floor vents.
4Floor/Windshield ± Air flows mainly from the floor vents
and windshield vents.
Set the air flow control dial to the floor/windshield position
turns on the defogging function with the purpose of
clearing the front view.
Use with the air intake control positioned in fresh. Press the ºA/Cº button for dehumidified heating or
cooling. This setting clears the front view more quickly.
5Windshield
± Air flows mainly from the windshield vents.
Set the air flow control dial to the windshield position turns
on the defogging function with the purpose of clearing the
front view.
This position allows the air intake to select FRESH
automatically. This is to clean up the front view more
quickly.
If you want to return the setting to RECIRCULATE mode,
press the air intake selector button one again.
Press ºA/Cº button for dehumidified heating or cooling.
This setting clears the front view more quickly.
2003 IS300 from Aug. '02 Prod. (OM53439U)

AIR CONDITIONING
186However, once selecting ºRECIRCULATED AIRº of the air
intake manually will make this function inoperable. In order to
make this function operable again, first select ºOUTSIDE AIRº
of the air intake, turn off the ignition switch, and start the engine
again. Then this function return to be operable.
If manual on±off of the air conditioning is desired ±
Push the ºA/Cº button to turn the air conditioning on and push
it again to turn the air conditioning off.
The air conditioning does not work if the outside temperature
is lowered down to around 0C (32F).
If the system is used for ventilation, heating in dry weather or
removing frost or exterior fog on the windshield, turn the air
conditioning off once it is no longer required. This will improve
fuel economy. The air conditioning can be used for year±round
automatic temperature control including cooling and
dehumidifying operation.
If the air conditioning compressor does not operate, the
indicator of the ºA/Cº button will blink. If the indicator of the
ºA/Cº button blinks even when the ºA/Cº button is pushed
again, have the compressor checked by your nearest Lexus
dealer.
(b) Windshield defogging and defrosting
SV21016
To remove interior fog on the windshield ±
1. Turn the air flow control dial to ºWINDSHIELDº.
2. Set the ºOUTSIDE AIRº mode.
To remove frost or exterior fog on the windshield ±
1. Turn the temperature control dial to the maximum
temperature.
2. Turn the air flow control dial to ºWINDSHIELDº.
3. Turn the fan speed control dial to ºHIº.
4. Leave the air conditioning on±off button off.
2003 IS300 from Aug. '02 Prod. (OM53439U)

AIR CONDITIONING
189
Heating
For best results, set controls to:
For automatic operation ±
Set the air flow control dial and the fan speed control
dial to ºAUTOº position.
Temperature ± To the desired temperature
Air intake ± OUTSIDE AIR
For manual operation ±Fan speed ± To the desired fan speed
Temperature ± Towards WARM (to the right)
Air intake ± OUTSIDE AIR
Air flow ± FLOOR
 For quick heating, select RECIRCULATED AIR for a few
minutes. To keep the windows from fogging, select
OUTSIDE AIR after the vehicle interior has been warmed.
 Push the ºA/Cº button on for dehumidified heating.
 Choose floor/windshield air flow to heat the vehicle interior
while defrosting or defogging the windshield. Air conditioning
For best results, set controls to:
For automatic operation ±
Set the air flow control dial and the fan speed control
dial to ºAUTOº position.
Temperature ± To the desired temperature
Air intake ± OUTSIDE AIR
For manual operation ±Fan speed ± To the desired fan speed
Temperature ± Towards COLD (to the left)
Air intake ± OUTSIDE AIR
Air flow ± PANEL
 For quick cooling, select RECIRCULATED AIR for a few
minutes.
Ventilation
For best results, set controls to:
For automatic operation ±
Set the air flow control dial and the fan speed control
dial to ºAUTOº position.
Temperature ± Towards low temperature
Air intake ± OUTSIDE AIR
2003 IS300 from Aug. '02 Prod. (OM53439U)

AIR CONDITIONING
190For manual operation ±
Fan speed ± To the desired fan speed
Temperature ± Towards COLD (to the left)
Air intake ± OUTSIDE AIR
Air flow ± PANEL
Defogging and defrosting
± The inside of the windshield
For best results, set controls to:
For automatic operation ±
Temperature ± Towards high temperature to heat; low temperature to cool
Air intake ± OUTSIDE AIR
AIR FLOW ± WINDSHIELD
For manual operation ±
Fan speed ± To the desired fan speed
Temperature ± Towards WARM (to the right) to heat;
COLD (to the left) to cool
Air intake ± OUTSIDE AIR
Air flow ± WINDSHIELD
Set the air flow control dial to the windshield or floor/windshield
position turns on the defogging function with the purpose of
clearing the front view. When turning the air flow selector to windshield position, the
air intake selects FRESH automatically.
This is to clean up the
front view more quickly.
If you want to return the setting to RECIRCULATE mode, press
the air intake selector button once again.
Press the ºA/Cº button for dehumidified heating or cooling. This
setting clears the front view more quickly.
 On humid days, do not blow cold air on the windshield ± the
difference between the outside and inside temperatures
could make the fogging worse.
± The outside of the windshield
For best results, set controls to:
For automatic operation ±
Temperature ± Towards high temperature
Air intake ± OUTSIDE AIR
Air flow ± WINDSHIELD
2003 IS300 from Aug. '02 Prod. (OM53439U)

AIR CONDITIONING
191
For manual operation ±
Fan speed ± To the desired fan speed
Temperature ± Towards WARM (to the right)
Air intake ± OUTSIDE AIR
Air flow ± WINDSHIELD
Set the air flow control dial to the windshield or floor/windshield
position turns on the defrosting function with the purpose of
clearing the front view.
When turning the air flow selector to windshield position, the
air intake selects FRESH automatically. This is to clean up the
front view more quickly.
If you want to return the setting to RECIRCULATE mode, press
the air intake selector button once again.
Press the ºA/Cº button for dehumidified heating or cooling. This
setting clears the front view more quickly.
 To heat the vehicle interior while defrosting the windshield,
choose floor/windshield air flow.
Center vents
SV21026
The center vents may be opened or closed as shown.
Side vents
SS21019
The side vents may be opened or closed as shown.
2003 IS300 from Aug. '02 Prod. (OM53439U)

STARTING AND DRIVING
225

To ensure that the three±way catalytic converter and
the entire emission control system operate properly,your vehicle must receive the periodic inspectionsrequired by the Lexus Maintenance Schedule . Forscheduled maintenance information, refer to theºOwner's Manual Supplement/ScheduledMaintenance º.ENGINE EXHAUST CAUTION
CAUTION
 Avoid inhaling the engine exhaust. It contains
carbon monoxide, which is a colorless and odorless
gas. It can cause unconsciousness or even death.
 Make sure the exhaust system has no holes or loose
connections. The system should be checked from
time to time. If you hit something, or notice a change
in the sound of the exhaust, have the system checked
immediately.
 Do not run the engine in a garage or enclosed area
except for the time needed to drive the vehicle in or
out. The exhaust gases cannot escape, making this
a particularly dangerous situation.
 Do not remain for a long time in a parked vehicle with
the engine running. If it is unavoidable, however, do
so only in an unconfined area and adjust the heating
or cooling system to force outside air into the vehicle.
 Keep the trunk lid or back door closed while driving.
An open or unsealed trunk lid or back door may
cause exhaust gases to be drawn into the vehicle.
2003 IS300 from Aug. '02 Prod. (OM53439U)

IN CASE OF AN EMERGENCY
271
IF YOUR VEHICLE OVERHEATS
If your engine coolant temperature gauge indicates
overheating, if you experience a loss of power, or if you
hear a loud knocking or pinging noise, the engine has
probably overheated.
When the engine overheats
Pull safely off the road, stop the vehicle and turn on your
emergency flashers. Put the transmission in ºPº (automatic)
or neutral (manual) and apply the parking brake.
A: If steam is coming from your engine:
Turn off the engine. Leave the hood closed until there is no sign
of steam or coolant. Your engine could have been seriously
damaged already. Call your Lexus dealer for assistance.
CAUTION
To help avoid personal injury, keep the hood closed until
there is no steam. Escaping steam or coolant is sign of
very high pressure.
B: If no steam is coming from your engine:
Leave the engine running and turn off the air conditioning.
Check the following.
Is the cooling fan operating?
 Is the coolant in the acceptable range?
 Is the engine drive belt O.K.?
CAUTION
When the eng ine is running, keep hands and clothing
away from the moving fan and engine drive belt.
 Do not attempt to remove the radiator cap when the
engine and radiator are hot. Serious injury could
result from scalding hot fluid and steam blown out
under pressure.
If the cooling fan is not operating or the coolant is not in the
acceptable range, turn off the engine and call your Lexus
dealer.
If both conditions are O.K., after the engine coolant
temperature has cooled to normal, continue driving your
vehicle.
If the engine coolant temperature does not cool down, or your
vehicle overheats again, have it checked as soon as possible
by your Lexus dealer.
2003 IS300 from Aug. '02 Prod. (OM53439U)

INTRODUCTION
301
ENGINE COMPARTMENT OVERVIEW
1Battery
2Fuse box
3Engine oil filler cap
4Engine oil leveldipstick
5Brake fluid reservoir
6Washer fluid tank
7Power steering fluidreservoir
8Engine coolantreservoir
9Electric cooling fans
10Condenser
11Radiator
2003 IS300 from Aug. '02 Prod. (OM53439U)
SV61007a