2010 Lexus GS350 fuel

441
4-2. Maintenance
4
Maintenance and care
GS_G_U (OM30C80U)
June 29, 2011 10:30 am
Emission inspection and maintenance (I/M) programs
Some states have vehicle emission inspection programs which include
OBD (On Board Diagnostics) checks. The OBD system monitors the oper-
ation of the emission control system.
■If the malfunction indicator lamp comes on
The OBD system determines that a problem exists somewhere in
the emission control system. Your vehicle may not pass the I/M test
and may need to be repaired. Contact your Lexus dealer to service
the vehicle.
■Your vehicle may not pass the I/M test:
●When the 12 volt battery is disconnected or discharged
Readiness codes that are set during ordinary driving are erased.
Also, depending on your driving habits, the readiness codes may
not be completely set.
●When the fuel tank cap is loose
The malfunction indicator lamp comes on as a temporary mal-
function and your vehicle may not pass the I/M test.
■When the malfunction indicator lamp goes off after several driv-
ing trips
The error code in the OBD system will not be cleared unless the
vehicle is driven 40 or more times.
■If your vehicle does not pass the I/M test
Contact your Lexus dealer to prepare the vehicle for re-testing.

444
4-3. Do-it-yourself maintenance
GS_G_U (OM30C80U)
June 29, 2011 10:30 am
CAUTION
The engine compartment contains many mechanisms and fluids that may move sud-
denly, become hot, or become electrically energized. To avoid death or serious injury,
observe the following precautions.
■When working on the engine compartment
●Keep hands, clothing, and tools away from the moving fan and engine drive belt.
●Be careful not to touch the engine, radiator, exhaust manifold, etc. right after driv-
ing as they may be hot. Oil and other fluids may also be hot.
●Do not leave anything that may burn easily, such as paper or rags, in the engine
compartment.
●Do not smoke, cause sparks or expose an open flame to fuel or the 12 volt battery.
Fuel and 12 volt battery fumes are flammable.
●Be extremely cautious when working on the 12 volt battery. It contains poisonous
and corrosive sulfuric acid.
■When working near the electric cooling fan or radiator grille
Be sure the “ENGINE START STOP” switch is OFF.
With the “ENGINE START STOP” switch in IGNITION ON mode, the electric
cooling fan may automatically start to run if the air conditioning is on and/or the
coolant temperature is high. (P. 4 5 7 )
■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.

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4-3. Do-it-yourself maintenance
4
Maintenance and care
GS_G_U (OM30C80U)
June 29, 2011 10:30 am
.
■Tire inflation pressure check interval
You should check tire inflation pressure every 2 weeks, or at least once a month.
If equipped, do not forget to check the spare.
■Effects of incorrect tire inflation pressure
Driving with incorrect tire inflation pressure may result in the following:
●Reduced fuel efficiency
●Reduced driving comfort and tire life
●Reduced safety
●Damage to the drive train
If a tire needs frequent refilling, have it checked by your Lexus dealer.
■Instructions for checking tire inflation pressure
When checking tire inflation pressure, observe the following:
●Check only when the tires are cold.
If your vehicle has been parked for at least 3 hours and has not been driven for
more than 1 mile or 1.5 km, you will get an accurate cold tire inflation pressure
reading.
●Always use a tire pressure gauge.
The appearance of the tire can be misleading. In addition, tire inflation pressures
that are even just a few pounds off can degrade ride and handling.
●Do not bleed or reduce tire inflation pressure after driving. It is normal for the
tire inflation pressure to be higher after driving.
●Never exceed the vehicle capacity weight.
Passengers and luggage weight should be placed so that the vehicle is bal-
anced.

491
4-3. Do-it-yourself maintenance
4
Maintenance and care
GS_G_U (OM30C80U)
June 29, 2011 10:30 am
FuseAmpereCircuit
18VGRS40VGRS
19MAIN30H-LP R LWR and H-LP L LWR
20STARTER30Starting system
21LH J/B-B30FL DOOR, RL DOOR and RAD
NO.3
22VVT40Electronic engine control system
23EPS80EPS
24ALT180
RH J/B-AM, LH J/B-AM, E/G-AM,
RR JB, HEATER, DEFOG, FAN1,
FAN2, ABS2, ABS MOTOR, 
ABS MAIN1, and ABS MAIN2
25RH J/B-AM80
AM1, OBD, STOP SW, TI & TE, 
PWR OUTLET, FR P/SEAT RH, 
STR LOCK, ECU-IG RH, RH-IG, 
ACC, CIG, SECURITY, 
FR S/HTR RH and AIR SUS
26FA N 380Electric cooling fans
27LH J/B-AM80
S/ROOF, P/SEAT, TV, FL S-HTR,
ECU-IG L, WIP, H-LP LVL, LH-IG,
FUEL OPN, A/C, PANEL, LH-B and
TRK OPN
28ABS230ABS
29DEFFOG50Rear window defogger, noise filter
30CDS40CDS

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4-3. Do-it-yourself maintenance
4
Maintenance and care
GS_G_U (OM30C80U)
June 29, 2011 10:30 am
FuseAmpereCircuit
24RR J/B80
STOP LP R, STOP LP L, RR-B, 
RR TAIL, RR FOG, RR-IG1, PSB, 
and RR S/SHADE
25GLW PLG150Starting system
26RH J/B-AM80
AM1, OBD, STOP SW, TI & TE, 
PWR OUTLET, FR P/SEAT RH, 
STR LOCK, ECU-IG RH, RH-IG, 
ACC, CIG, SECURITY, 
FR S/HTR RH and AIR SUS
27ABS230ABS
28DEFFOG50Rear window defogger, noise filter
29CDS40CDS
30FA N 140Electric cooling fans
31HEATER50Air conditioning system
32GLW PLG250Starting system
33E/G-AM60H-LP CLN, FR CTRL ALT, A/C
COMP and STB-AM
34LH J/B-AM80
S/ROOF, P/SEAT, TV, FL S-HTR,
ECU-IG L, WIP, H-LP LVL, LH-IG,
FUEL OPN, A/C, PANEL, LH-B and
TRK OPN
35FA N 260Electric cooling fans

496
4-3. Do-it-yourself maintenance
GS_G_U (OM30C80U)
June 29, 2011 10:30 am
■Engine compartment (Type B)
GS460
FuseAmpereCircuit
1FR CTRL-B25H-LP UPR and HORN
2A/F15Exhaust system
3ETCS10Electronic throttle control system
4ALT-S7. 5 Charging system
5INJ225
Multiport fuel injection system/
sequential multiport fuel injection
system
6H-LP CLN30Headlight cleaner
7STB-AM30
8DEICER25
9FR CTRL-AM30FR TAIL, FR FOG and WASHER

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4-3. Do-it-yourself maintenance
4
Maintenance and care
GS_G_U (OM30C80U)
June 29, 2011 10:30 am
FuseAmpereCircuit
10IG210Ignition system, noise filter and ECT
ECU
11EFI NO.210
Fuel system, exhaust system, multi-
port fuel injection system/sequential
multiport fuel injection system, elec-
tronic engine control system, leak
detection pump
12H-LP R LWR15Headlight low beam (right)
13H-LP L LWR15Headlight low beam (left)
14F/ P M P25Fuel system
15EFI25
Multiport fuel injection system/
sequential multiport fuel injection
system, ECT ECU
16INJ25
Multiport fuel injection system/
sequential multiport fuel injection
system
17H-LP UPR15Headlight high beams
18HORN10Horns
19WA S H E R20Windshield wipers and washer
20FR TAIL10Parking lights, side marker light
21FR FOG15Front fog lights

498
4-3. Do-it-yourself maintenance
GS_G_U (OM30C80U)
June 29, 2011 10:30 am
GS350
FuseAmpereCircuit
1FR CTRL-B25H-LP UPR and HORN
2A/F15Exhaust system
3ETCS10Electronic throttle control system
4ALT-S7. 5 Charging system
5H-LP CLN30Headlight cleaner
6A/C COMP7. 5 Air conditioning system
7DEICER25
8FR CTRL-AM30FR TAIL, FR FOG and WASHER
9IG210Ignition system and noise filter
10EFI NO.210Fuel system and exhaust system