2003 Lexus GS300 Electrical Components

SECTION 6 ± 4
SERVICE PROCEDURES AND
SPECIFICATIONS
Electrical components
Specifications 292. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Checking battery condition296 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Battery recharging precautions298 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Checking and replacing the blade type fuses299 . . . . . . . . . . . . . . . .
Checking the cartridge type fuses301 . . . . . . . . . . . . . . . . . . . . . . . . . .
Adding washer fluid303 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Checking the headlight aim303 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Replacing light bulbs309 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SPECIFICATIONS
± FUSE LOCATION
64G004b

1Engine compartment
2Passenger's side kick panel
3Driver's side kick panel
4Engine compartment
± FUSES
64G015b

Driver's side kick panel
64G014b

Passenger's side kick panel

64G013e

Engine compartment
64G026d

Engine compartment

No.FUSEAMPERECIRCUIT
1 WASHER20Windshield washer
2 FR FOG15Fog lights
3 TAIL10Tail lights, Side marker lights,
License plate lights,
Parking lights
4 GAUGE10Back±up lights, Gauges and
meters, service reminder
indicators and buzzers
5 FUEL OPN10Fuel filler door opener
6 PANEL7.5Emergency flashers,
Headlight cleaner
7 HEATER10Air conditioning
8 SRS±B5Gauges and meters, service
reminder indicators and
warning buzzers
9 D P/SEAT30Power seat system
10 RADIO
NO.215Audio, Shift lock system
11 WIPER25Windshield wipers
12 OBD7.5On±board diagnosis
13 STOP15Stop lights,
Anti±lock brake system,
Traction control system
No.FUSEAMPERECIRCUIT
14 CIG15Cigarette lighter, Power outlet
15 ECU±IG15Power window, Door lock
system, Wireless remote
control, Theft deterrent system
16 STARTER5Starting system
17 IGN5
Multiport fuel injection
system/sequential multiport fuel
injection system, SRS,
Anti±lock brake system,
Vehicle skid control system,
Cruise control system
18 D RR
DOOR20Power window system,
Door lock system,
Wireless remote control
19 RR FOG10No circuit
20 MIR HTR10Outside rear view mirror
21 S/ROOF25Moon roof
22 ECU±B320Power window system,
Door lock system,
Wireless remote control
23 P P/SEAT30Power seat system,
Tilt and telescopic steering
24 DOME10Interior lights, Personal lights,
Vanity lights, Trunk light, Clock
25 SEAT HTR20Seat heater

No.FUSEAMPERECIRCUIT
26 4WS25No circuit
27 TV15No circuit
28 ECU±B210Power seat system
29 P RR
DOOR20Power window system,
Door lock system,
Wireless remote control
30 ECU±B120
Power window system,
Door lock system,
Wireless remote control,
Theft deterrent system, Trunk
lid opener, Interior lights,
Personal lights, Clock,
Headlight cleaner
31 P FR
DOOR20Power window system,
Door lock system,
Wireless remote control
32 D FR
DOOR20Power window system, Door
lock system, Wireless remote
control
33 HORN10Horn
34 ETCS15Electronic throttle control
system
35 AM215Starting system, Multiport fuel
injection system/sequential
multiport fuel injection system
36 TEL15No circuit
37 TURN±HAZ10Turn signal lights
No.FUSEAMPERECIRCUIT
38 EFI25
Multiport fuel injection
system/sequential multiport fuel
injection system, Emission
control system
39 ALT±S5Charging system
40 RADIO
NO.130Audio
41 DRL NO.230Daytime running light system
42 DRL NO.130Daytime running light system
43 H±LP L
LW R15Left±hand headlight (low beam)
44 H±LP R
LW R15Right±hand headlight (low
beam)
45 H±LP R
UPR15Right±hand headlight (high
beam)
46 H±LP L
UPR15Left±hand headlight (high
beam)
SPARESpare fuse

CHECKING BATTERY CONDITION
Precautions
CAUTION
BATTERY PRECAUTIONS
The battery produces flammable and explosive
hydrogen gas.
Do not cause a spark by contacting the battery
terminals with tools.
Do not smoke or light a match near the battery.
The electrolyte contains poisonous and corrosive
sulfuric acid.
Avoid contact with eyes, skin or clothes.
Never inhale or swallow electrolyte.
Wear protective safety glasses when working near
the battery.
Keep children away from the battery.
EMERGENCY MEASURES
If electrolyte gets in your eyes, flush your eyes with
clean water for at least 15 minutes and get immediate
medical attention. If possible, continue to apply
water with a sponge or cloth while traveling to the
medical office.
If electrolyte gets on your skin, thoroughly wash the
contacted area. If you feel a pain or burn, get medical
attention immediately.
If electrolyte gets on your clothes, there is a
possibility of its soaking through to your skin, so
immediately take off the exposed clothing and follow
the procedure above, if necessary.
If you accidentally swallow electrolyte, drink a large
quantity of water or milk. Follow with milk of
magnesia, beaten raw egg or vegetable oil. Then go
immediately for emergency help.
Warning: Battery posts, terminals and related
accessories contain lead and lead compounds,
chemicals known to the State of California to cause
cancer and reproductive harm. Wash hands after
handling.

Checking battery exterior
64G001a

1Terminals 2Hold±down clamp
Check the battery for corroded or loose connections,
cracks, or loose hold±down clamps.
1. If the battery is corroded, wash it off with a solution of warm
water and baking soda. Coat the terminals with grease to
prevent further corrosion.
2. If the connections are loose, tighten the clamp bolts ± but do
not overtighten.
3. Tighten the hold±down clamp only enough to keep the
battery firmly in place. Overtightening may damage the battery
case.
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.

Checking battery condition
Checking by indicator
64G003a
Check the battery condition by the indicator color.
1
BLUE ± Good condition.
2
WHITE ± Charging necessary. Have the battery checked
by your Lexus dealer.
3
RED ± Have the battery checked by your Lexus dealer.
NOTICE
Do not refill the battery with water.
BATTERY RECHARGING
PRECAUTIONS
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, be sure all accessories are turned off.