air conditioning Lexus GS450h 2007 Using the hands-free system (for cellular phone) / LEXUS 2007 GS450H THROUGH JUNE 2006 PROD. (OM30727U) Owner's Guide

357
4-3. Do-it-yourself maintenance
4
Maintenance and care
CAUTION
■When working near the electric cooling fan or radiator grille
Be sure the power switch is “OFF”.
With the power switch in “IG-ON” mode, the electric cooling fan may automati-
cally start to run if the air conditioning is on and/or the coolant temperature is high. 
(  P. 3 6 9 )
■Safety glasses
Wear safety glasses to prevent flying or falling material, fluid spray, etc. from getting
in the eyes.
NOTICE
■If you remove the air cleaner filter
Driving with the air cleaner filter removed may cause excessive engine wear due to
dirt in the air. Also a backfire could cause a fire in the engine compartment.

391
4-3. Do-it-yourself maintenance
4
Maintenance and care
Air conditioning filter
The air conditioning filter must be changed regularly to maintain air condi-
tioning efficiency.
Set the air conditio ning system to recirculated mode.
The air conditioning filter case cannot be removed with the system in
the outside air mode.
Turn the power switch to “OFF” mode.
Open the glove box and
r
emove the partition.
Remove the filter cover.
Push the tabs and remove the
filter case.
STEP1
STEP2
STEP3
STEP4
STEP5

392
4-3. Do-it-yourself maintenance
■Changing interval
Inspect and replace the air conditioning filter according to the maintenance sched-
ule. In dusty areas or areas with heavy traffic flow, early replacement may be
r
equired. (For scheduled maintenance information, refer to the “Warranty and Ser -
vices Guide/Owner's Manual Supp le
ment/Scheduled Maintenance”.)
■If air flow from the vents decreases dramatically
The filter may be clogged. Check the filter and replace if necessary.
NOTICE
■When using the air conditioning system
Make sure that a filter is always installed. 
Using the air conditioning system without a filter may cause damage to the system.
Remove the air conditioning fil-
ter from the filter case and
r

eplace it with a new one.
The “ UP” marks shown on the
filter and the filter case should
be pointing up.
STEP6

402
4-3. Do-it-yourself maintenance
FuseAmpereCircuit
23A/F15Fuel system
24INV W/P10Hybrid system
25IGCT No.120Hybrid system, IGCT No.2, 
IGCT No.3
26FR FOG15Fog light
27FR TAIL10Tail light, rear side marker light
28WA S H20Windshield washer
29HORN10Horn
30H-LP HI20Headlight high beam
31DC/DC140Charging system
32RAD FAN60Electric cooling fans
33LH J/B AM80
S/ROOF, FR P/SEAT LH, TV, A/C,
FUEL OPN, FR WIP, H-LP LVL, 
FR S/HTR LH, A/C W/P
34E/G AM60H-LP CLN, FR CTRL-AM, DEICER,
STB AM
35HEATER50Air conditioning system
36DEFOG50Rear window defogger
37ABS230VSC, ABS
38RH J/B-AM80
AM1, OBD, STOP SW, TI & TE, 
FR P/SEAT RH, STR LOCK, 
SECURITY, ECU-IG R, RH-IG, 
F S/HTR RH, CIG, PWR OUTLET, 
AIR SUS

404
4-3. Do-it-yourself maintenance
■Driver’s side instrument panel
FuseAmpereCircuit
1FR WIP30Windshield wipers
2RR-IG7. 5RR-IG1
3LH-IG10
Emergency flashers, seat belt preten-
sioners, headlight cleaners, exhaust
system, rear window defogger, elec-
tric cooling fans, front left door con-
trol system, rear left door control
system
4H-LP LVL7. 5Adaptive front lighting system
5A/C W/P7. 5Air conditioning system
6RAD No.310Audio system
7FR DOOR LH20Front left door control system
8RR DOOR LH20Rear left door control system
9FR S/HTR LH15Seat heaters, seat heaters and venti-
lators
10ECU-IG LH10
VGRS, EPS, electronically con-
trolled brake system, yaw rate & G
sensor, dynamic radar cruise control
system, rear view monitor system,
moon roof

405
4-3. Do-it-yourself maintenance
4
Maintenance and care
FuseAmpereCircuit
11PA N E L7. 5
Steering switches, distance control
switch, audio system, glove box light,
switch illumination, cigarette lighter,
shift lever light, touch screen, rear
personal lights
12S/ROOF25
13FUEL OPEN10Fuel lid opener, trunk opener
14LH-B10Anti-theft system
15TRK OPN10Trunk opener
16TV7. 5Touch screen, rear view monitor sys-
tem
17A/C7. 5Air conditioning system
18FR P/SEAT LH30Po w e r s e a t

406
4-3. Do-it-yourself maintenance
■Passenger’s side instrument panel
FuseAmpereCircuit
1ECU-IG RH10
Electric tilt and telescopic steering,
combination switch, power seat,
smart access system with push-but-
ton start, air conditioning system,
touch screen, shift lock system, tire
pressure warning system, front/rear
stabilizer system
2FR S/HTR RH15Seat heaters, seat heaters and venti-
lators
3RH-IG7. 5
Front right door control system, rear
right door control system, seat belt
pretensioners, transmission, seat
heaters, seat heaters and ventilators
4AM215Starting system
5FR DOOR RH20Front right door control system
6RR DOOR RH20Rear right door control system
7AIR SUS20AV S
8PWR OUTLET15Po w e r o u t l e t
9CIG15Cigarette lighter

5
When trouble arises
427
5-1. Essential information
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 v
ehicle
(Water dripping from the air conditioning after use is normal.)
● Flat
-looking tires or uneven tire wear
●Engine coolant temper atur
e gauge needle continually points
higher than normal
■ A
udible symptoms
●Changes in e
xhaust sound
● Ex
cessive tire squeal when cornering
●Str
ange noises related to the suspension system
●P
inging or other noises related to the hybrid system
■ Oper
ational symptoms
●Engine mis
sing, stumbling or running rough
●A
ppreciable loss of power
●V
ehicle pulls heavily to one side when braking
●V
ehicle pulls heavily to one side when driving on a level road
● L
oss of brake effectiveness, sp ongy feeling, pedal almost touches
the floor

5
When trouble arises
475
5-2. Steps to take in an emergency
If your vehicle overheats
■Electric motor (traction motor) and inverter
If the message “HYBRID SYSTEM OVERHEAT” is displayed on the
multi-information display.
■ Ga
soline engine
If the needle of the engine co olant temper
ature gauge enters the
red zone, the gasoline engine has probably overheated.
Observe the following steps: Stop the vehicle in a safe place and turn of
f the automatic air
conditioning system.
Check to see if steam is coming out from under the hood.
If you see steam: 
Stop the hybrid system and carefully lift the hood.
If you do not see steam: Leave the hybrid system running and carefully lift the hood.
Remove the engine compartment cover. ( P. 362 )
Check to see if the cooling fan is operating.
If the fan is operating: 
Wait until the engine coolant temperature gauge begins to
fall and then stop the hybrid s
ystem.
If the fan is not operating: 
Stop the hybrid system immed iately and call y
our local
Lexus dealer.
After the hybrid system has
cooled do
wn sufficiently, check
the coolant level and inspect the
radiator core (radiator) for any
leaks.
STEP1
STEP2
STEP3
STEP4
STEP5

497
6-1. Specifications
6
Vehicle specifications
Warning: The temperature grades for this tire are established for a tire that
is properly inflated and not overloaded.
Excessive speed, underinflation, or excess iv
e loading, either separately or in
combination, can cause heat build up 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
Maximum inflation pres-
sureThe maximum cold inflated pressure to which a tire
may be inflated, shown on the sidewall of the tire
Maximum loaded vehicle
weight
The sum of: 
(a) Curb weight 
(b) Accessory weight 
(c) Vehicle capacity weight 
(d) Production options weight
Normal occupant weight150 lb. (68 kg) times the number of occupants speci-
fied in the second column of Table 1
* that follows