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GS450h_OM_OM30F70U_(U)
4176-2. Maintenance
6
Maintenance and care
CAUTION
■If your vehicle is not properly maintained
Improper maintenance could result in serious damage to the vehicle and possible
death or serious injury.
■Handling of the 12-volt battery
●Engine exhaust, some of its constituents, and a wide variety of automobile com-
ponents contain or emit chemicals known to the State of California to cause can-
cer and birth defects and other reproductive harm. Work in a well ventilated area.
●Oils, fuels and fluids contained in vehicles as well as waste produced by compo-
nent wear contain or emit chemicals known to the State of California to cause
cancer and birth defects or other reproductive harm. Avoid exposure and wash
any affected area immediately.
●12-volt battery posts, terminals and related accessories contain lead and lead
compounds which are known to cause brain damage. Wash your hands after
handling. (→P. 4 3 9 )
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6-2. Maintenance
Emission inspection and maintenance (I/M)
programs
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.
●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 indicating a temporary mal-
function and your vehicle may not pass the I/M test.
The error code in the OBD system will not be cleared unless the vehicle is
driven 40 or more times.
Contact your Lexus dealer to prepare the vehicle for re-testing.
Some states have vehicle emission inspection programs which include
OBD (On Board Diagnostics) checks . The OBD system monitors the
operation of the emission control system.
If the malfunction indicator lamp comes on
Your vehicle may not pass the I/M test in the following situations:
When the malfunction indicator lamp still remains on after several
driving trips
If your vehicle does not pass the I/M test
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GS450h_OM_OM30F70U_(U)
4256-3. Do-it-yourself maintenance
6
Maintenance and care
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
●Make sure that the “POWER ON” on the multi-information display and the
“READY” indicator are both off.
●Keep hands, clothing and tools away from the moving fan and engine drive belt.
●Be careful not to touch the engine, power control unit, radiator, exhaust manifold,
etc. right after driving as they may be hot. Oil and other fluids may also be hot.
●Do not leave anything that may burn easily, such as paper and rags, in the engine
compartment.
●Do not smoke, cause sparks or expose an open flame to fuel. Fuel fumes are flam-
mable.
■When working near the electric cooling fans or radiator grille
Be sure the power switch is off.
With the power switch in ON mode, the electric cooling fans may automatically
start to run if the air conditioning is on and/or the coolant temperature is high.
(→ P. 4 3 6 )
■Safety glasses
Wear safety glasses to prevent flying or falling material, fluid spray, etc. from get-
ting in your 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.
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6-3. Do-it-yourself maintenance
Ti r e v a l v e
Tire pressure gauge
Remove the tire valve cap.
Press the tip of the tire pressure gauge onto the tire valve.
Read the pressure using the gauge gradations.
If the tire inflation pressure is not at the recommended level, adjust the
pressure.
If you add too much air, press the center of the valve to deflate.
After completing the tire inflation pressure measurement and adjust-
ment, apply soapy water to the valve and check for leakage.
Put the tire valve cap back on.
■Tire inflation pressure check interval
You should check tire inflation pressure every two weeks, or at least once a month.
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 economy
●Reduced driving comfort and poor handling
●Reduced tire life due to wear
●Reduced safety
●Damage to the drive train
If a tire needs frequent inflating, have it checked by your Lexus dealer.
Inspection and adjustment procedure
1
2
1
2
3
4
5
6
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466
GS450h_OM_OM30F70U_(U)
6-3. Do-it-yourself maintenance
■Engine compartment
Fuse layout and amperage ratings
FuseAmpereCircuit
1IGN10Starting system
2INJ10Multiport fuel injection system/sequential
multiport fuel injection system
3EFI NO.210Air intake system, exhaust system
4IG2 MAIN20IGN, GAUGE, INJ, AIR BAG, IG2 NO.1,
LH-IG2
5EFI MAIN25Multiport fuel injection system/sequential
multiport fuel injection system, EFI NO.2
6A/F15Air flow sensor
7EDU20Multiport fuel injection system/sequential
multiport fuel injection system
8F/ P M P25Multiport fuel injection system/sequential
multiport fuel injection system
9H-LP RH-LO20Right-hand headlight (low beam)*
10H-LP LH-LO20Left-hand headlight (low beam)*
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GS450h_OM_OM30F70U_(U)
4676-3. Do-it-yourself maintenance
6
Maintenance and care
11ABS MAIN 210Brake system
12ABS MAIN 110Brake system
13IGCT NO.130IGCT NO.2, IGCT NO.3, IGCT NO.4,
IGCT NO.5
14ECU-B7. 5VGRS, smart access system with push-but-
ton start
15INV W/P10Hybrid system
16ETCS10Multiport fuel injection system/sequential
multiport fuel injection system
17EPS-B10Electric power steering system
18D/C CUT30DOME, MPX-B
19HORN10Horn
20ODS5Occupant classification system
21TV7. 5Remote Touch screen
22P/ I - B N O. 280IG2 MAIN, EFI MAIN, EDU, F/PMP, A/F
23ABS NO.230Motor relay
24P/ I - B N O.150H-LP HI RH, H-LP HI LH, DRL
25H-LP LO30H-LP LO RH, H-LP LO LH
26LH J/B-B40Left-hand junction block
27RH J/B-B40Right-hand junction block
28VGRS40VGRS
29OIL PMP60Oil pump
30IGCT NO.57. 5Power management system, shift position
sensor
31WIP-S7. 5Windshield wipers, driver support system
32WA S H - S5Windshield washer, driver support system
33COMB SW5Windshield wipers
FuseAmpereCircuit
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GS450h_OM_OM30F70U_(U)
4716-3. Do-it-yourself maintenance
6
Maintenance and care
11DOOR FL30Outside rear view mirror defoggers, power
window (front left-hand)
12CAPACITOR
(HV)10Capacitor
13STRG LOCK15Steering lock system
14D/L NO.225Po w e r d o o r l o c k s y s t e m
15DOOR RL30Power window (rear left-hand)
16HAZ15Turn signal lights, emergency flashers
17LH-IG210
Multiport fuel injection system/sequential
multiport fuel injection system, stop lights,
smart access system with push-button start,
steering lock system, brake system, power
management system
18LH J/B-B7. 5Body ECU
19S/ROOF20Moon roof
20P/ S E AT 2 F/ L25Po w e r s e a t s
21TI & TE20Electric tilt and telescopic steering column
22A/C7. 5Air conditioning system
FuseAmpereCircuit
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5067-2. Steps to take in an emergency
GS450h_OM_OM30F70U_(U)After taking the specified steps to correct the suspected problem, check
that the warning light goes off.
Brake system warning light
Indicates a malfunction in:
• The electronically controlled brake system;
• The regenerative braking system; or
• The parking brake system
Follow the correction procedures.
Warning lightWarning light/Details
Warning lightWarning light/DetailsCorrection procedure
Open door warning light
(warning buzzer)
*1
Indicates that a door or the
trunk is not fully closed
Check that all the doors and
the trunk are closed.
Low fuel level warning lightIndicates remaining fuel is
approximately 2.6 gal. (10.0
L, 2.2 Imp.gal.) or less
Refuel the vehicle.
Seat belt reminder light (warn-
ing buzzer)
*2
Warns the driver and/or front
passenger to fasten their seat
belts
Fasten the seat belt.If the front passenger’s seat is
occupied, the front passen-
ger’s seat belt also needs to
be fastened to make the
warning light (warning
buzzer) off.
Master warning lightA buzzer sounds and the
warning light comes on and
flashes to indicate that the
master warning system has
detected a malfunction.
→ P. 5 1 3
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