turn Lexus GX470 2003 Electrical Components / LEXUS 2003 GX470 OWNER'S MANUAL (OM60979U)

CHASSIS
430
CHECKING BRAKE FLUID
To check the fluid level, simply look at the seethrough
reservoir. The level should be between the “MAX” and
“MIN” lines on the tank.
It is normal for the brake fluid level to go down slightly as the
brake pads wear or when the fluid level in the accumulator is
high.
If the reservoir needs frequent refilling, it may indicate a serious
mechanical problem.
If the level is low, add FMVSS No.116 DOT 3 or SAE J1703
brake fluid to the brake reservoir. Refilling brake fluid:
1. Turn the ignition switch off.
2. Depress the brake pedal more than 40 times.
3. Remove the reservoir cap by hand. Add brake fluid up to
the “MAX” line.
If you do not follow the procedure above, the reservoir may
overflow.
Use only newly opened brake fluid. Once opened, brake fluid
absorbs
moisture from the air, and excess moisture can cause
a dangerous loss of braking efficiency.CAUTION
Take care when filling the reservoir because brake fluid
can harm your hands or eyes and damage painted
surfaces. If fluid gets in your eyes, flush them with clean
water immediately. If you still feel uncomfortable with
your eyes, go to the doctor.
NOTICE
If you spill some of the fluid, be sure to wipe it off to
prevent it from damaging the parts or paintwork.

CHASSIS
431
CHECKING POWER STEERINGFLUID
The power steering fluid reservoir is located under the
right side engine compartment cover. Before checking
the power steering fluid, remove the cover. (For details,
see “Removing the engine compart covers” on page 405.)
Check the fluid level, simply look at the seethrough
reservoir. If necessary, add automatic transmission fluid
DEXRON
II or III .
If the vehicle has been driven around 80 km/h (50 mph) for 20
minutes (a little more in frigid temperatures), the fluid is hot
(60 C − 80C or 140F − 175F). You may also check the level
when the fluid is cold (about room temperature, 10 C − 30C
or 50F − 85F) if the engine has not been run for about five
hours.
 1 If cold O.K.2 If cold add3 If hot O.K.
4 If hot add
Clean all dirt off the reservoir and look at the fluid level. If the
fluid is cold, the level should be in the “COLD” range. Similarly,
if it is hot, the fluid level should be in the “HOT” range. If th\
e
level is at the low side of the appropriate range, add automatic
transmission fluid DEXRON
II or III to bring the level within
the range.
To remove the reservoir cap, turn it counterclockwise and lift
up. To reinstall it, turn it clockwise. After replacing the reservoir
cap, visually check the steering box case, vane pump and hose
connections for leaks or damage.

CHASSIS
436Warning: The traction grade assigned to this tire is based on
braking (straight ahead) traction tests and does not include
cornering (turning) traction.
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 failure. The grade C
corresponds to a level of performance which all passenger car
tires must meet under the Federal Motor Vehicle Safety
Standard No. 109. 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.
Tire selection
When replacing a tire, use a tire of the same size and
construction, and the same or greater load capacity as the
originally installed tires. Also, all the tires must be the
same brand and have the same tread patterns.
Using any other size or type of tire may seriously affect
handling, ride, speedometer/odometer calibration, ground
clearance, and clearance between the body and tires or snow
chains.
CAUTION
Observe the following instructions. Otherwise, an
accident may occur resulting in death or serious
injuries.
 Do not mix radial, bias belted, or biasply tires on
your vehicle, as this may cause dangerous handling
characteristics resulting in loss of control.
 Do not use tires other than the manufacturer’s
recommended size, as this may cause dangerous
handling characteristics resulting in loss of control.
 Do not use tires of different brands, sizes,
construction or tread patterns, as this may cause
dangerous handling characteristics result ing in loss
of control.

CHASSIS
439
Chain installation
Install the chains on the rear tires as tightly as possible.
Do not use tire chains on the front tires. Retighten chains
after driving 0.5 1.0 km (1/4 1/2 mile).
When installing chains on your tires, carefully follow the
instructions of the chain manufacturer.
CAUTION
Do not exceed 50 km/h (30 mph) or the chain
manufacturer’s recommended speed limit,
whichever is lower.
 Drive carefully avoiding bumps, holes, and sharp
turns, which may cause the vehicle to bounce.
 Avoid sharp turns or lockedwheel braking, as use of
chains may adversely affect vehicle handling.
 When driving with chains installed, be sure to drive
carefully. Slow down before entering the curves to
avoid losing control of the vehicle. Otherwise an
accident may occur.
NOTICE
When jacking up or installing tire chains, be sure to turn
off the rear height control air suspension with the
“HEIGHT CONTROL OFF” switch and stop the engine.
Otherwise, the vehicle height may change because of
the automatic leveling function resulting in accident.
REPLACING WHEELS
When to replace your wheels
If you have wheel damage such as bending, cracks or
heavy corrosion, the wheel should be replaced.
If you fail to replace damaged wheels, the tire may slip off the
wheel or cause loss of handling control.
Replacement with used wheels is not recommended as they
may have been subjected to rough treatment or high mileage
and could fail without warning. Also, bent wheels which have
been straightened may have hidden structural damage and
therefore should not be used. Never use an inner tube in a
leaking wheel which is designed for a tubeless tire.
Wheel selection
When replacing wheels, care should be taken to ensure
that they are equivalent to those removed in load capacity,
diameter, rim width, and offset.
Correct replacement wheels are available at your Lexus
dealer.
A wheel of a different size or type may adversely affect
handling, wheel and bearing life, brake cooling,
speedometer/odometer calibration, stopping ability, headlight
aim, bumper height, vehicle ground clearance, and tire or snow
chain clearance to the body and chassis.

ELECTRICAL COMPONENTS
446
No.FUSEAMPERECIRCUIT
33 ABSSOL50
Anti −lock brake system,
vehicle skid control system,
active traction control system,
brake assist system
34 ALTS7.5Charging system
35 MAYDAY7.5Lexus link system
36 HORN10Horns
37 TRNHAZ15Turn signal lights
38 ETCS10Electronic throttle control system
39 EFI20Multiport fuel injection
system/sequential multiport fuel
injection system
40 D FR P/W20Power window
41 DR/LCK25Power door lock
42 TOWING30Towing converter
43 RADIO
NO.230Car audio system, navigation
system
44 IGN10
Multiport fuel injection
system/sequential multiport fuel
injection system, vehicle skid
control system
45 SRS10SRS airbag system
46 GAUGE7.5Gauges and meters
47 ST27.5Multiport fuel injection
system/sequential multiport fuel
injection system
No.FUSEAMPERECIRCUIT
48 FR
WIPWSH30Windshield wipers, windshield
washer
49 TEMS20Electronic modulated suspen-
sion
50 DIFF20Four−wheel drive system
51 RR WIP15Rear window wiper
52 D P/SEAT30Driver’s power seats
53 P P/SEAT30Front passenger’s power seats
54 PWR
OUTLET15Power outlet (12 VDC)
55 IG1 NO.210Rear air conditioning system, in-
side rear view mirror
56 RR WSH15Rear window washer
57 ECUIG10
Shift lock control system, power
windows, outside rear view
mirror defogger, anti −lock brake
system, active traction control
system, vehicle skid control
system, air conditioning system,
navigation system, power
windows, moon roof, Lexus link
system, tilt and telescopic
steering, multi −information
display, driving position
memory system
58 IG110
Air conditioning system, back −up
lights, rear window defogger,
seat heaters, vehicle skid control
system

ELECTRICAL COMPONENTS
449
NOTICE
Make sure the engine and all accessories are turned
off before performing maintenance.
 When checking the battery, remove the ground cable
first and reinstall it last.
 Be careful not to cause a short circuit with tools.
 Take care no solution gets into the battery when
washing it.
If the battery is disconnected or run down
The power windows and moon roof may not operate
automatically and the jam protection function will not function
correctly after you reconnect, replace or recharge the battery.
In any of these cases, you should normalize the power
windows and moon roof. To normalize the power windows and
moon roof, see pages 35 and 88.
Checking battery condition
Check the battery condition by the indicator color.
1BLUE − Good condition.
2WHITE − Charging necessary. Have the battery checked
by your Lexus dealer.
3RED − Have the battery checked by your Lexus dealer.
NOTICE
Do not refill the battery with water.

ELECTRICAL COMPONENTS
450
BATTERY RECHARGINGPRECAUTIONS
During recharging, the battery is producing hydrogen
gas.
Therefore, before recharging:
1. If recharging with the battery installed on the vehicle, be
sure to disconnect the ground cable.
2. Make sure the power switch on the recharger is off when
connecting the charger cables to the battery and when
disconnecting them.
CAUTION
Always charge the battery in an unconfined area. Do
not charge the battery in a garage or closed room
where there is not sufficient ventilation.
 Only do a slow charge (5 A or less). Charging at a
quicker rate is dangerous. The battery may explode
causing personal injuries.
NOTICE
Never recharge the battery while the engine is running.
Also, make sure all accessories are turned off.
CHECKING AND REPLACING THE BLADE TYPE FUSES
The engine compartment fuse box is located under the left
side engine compartment cover. Before checking the
engine compartment fuses, remove the cover. (For
details, see “Removing the engine compartment covers”
on page 405.)
Engine compartment
1
Pullout tool 2
Spare fuses

ELECTRICAL COMPONENTS
451
 Driver’s side instrument panel
1. Turn the ignition switch off and open the fuse box lid.
Determine which fuse may be causing the problem. The lid of
the fuse box shows the name of the circuit for each fuse.2. Make sure the inoperative component is turned off. Pull
the suspected fuse straight out with the pullout tool and
check it. If it has blown, push a new fuse into the clips.

ELECTRICAL COMPONENTS
452
 Good  Blown
a. Look carefully at the fuse. If the thin wire is broken, the fuse
has blown. If you are not sure or if it is too dark to see, try
replacing the suspected fuse with one of the same value that
you know is good.
b. Only install a fuse with the amperage rating designated on
the fuse box lid.
If you do not have a spare fuse, in an emergency you can pull
out the “CIG”, “RADIO NO.1” or “SEAT HEATER” fuse, which
may be dispensable for normal driving, and use it if its
amperage rating is the same.
If you cannot use one of the same amperage, use one lower
than, but as close as possible to, the amperage. If the
amperage is lower than that specified, the fuse might blow out
again but this does not indicate anything wrong. Be sure to get
the correct fuse as soon as possible and return the substitute
to its original clips. It is a good idea to purchase a set of spare fuses and keep them
in your vehicle for emergencies.
If the new fuse immediately blows out, there is a problem with
the electrical system. Have your Lexus dealer correct it as
soon as possible.
CAUTION
Never use a fuse with a higher amperage rating, or any
other object, in place of a fuse. This may cause
extensive damage and possibly a fire.

ELECTRICAL COMPONENTS
455
REPLACING LIGHT BULBS
The illustrations on the following pages show the locations of
light bulbs. If it is necessary to replace a bulb, take your vehicle
to your Lexus dealer as soon as possible. Use bulbs with the
bulb numbers and wattage ratings given in the table.
CAUTION
 To prevent burning yourself, do not replace the light
bulbs while they are hot.
 Halogen bulbs have pressurized gas inside and
require special handling. They can burst or shatter if
scratched or dropped. Hold a bulb only by its plastic
or metal case. Do not touch the glass part of a bulb
with bare hands.
NOTICE
Only use a bulb of the listed type.
The inside of the lens of exterior lights such as headlights may
temporarily fog up when the lens becomes wet in the rain or in
a car wash. This is not a problem because the fogging is
caused by the temperature dif ference between the outside and
inside of the lens, just like the windshield fogged up in the rain.
However, if there is a large drop of water on the inside of the
lens, or if there is water pooled inside the light, contact your
Lexus dealer. LIGHT LOCATION
Light Bulbs Bulb No. W Type
1Headlights (High beam) 9005 60 A
2Headlights (Low beam)
−−55 B
3Front side marker lights 168 5 C
4Front turn signal lights 4157NAK 27/8 D
5Parking lights 168 5 C
6Fog lights −−55 E