2010 Lexus HS250h fuel

415
4-2. Maintenance
4
Maintenance and care
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 pr
oblem 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.
■ Y
our vehicle may not pass the I/M test in the following situations:
●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 r
eadiness codes may
not be completely set.
● When the fuel tank cap is loose
The malfunction indicator lamp comes on indicating a temporary
malfunction and y

our vehicle may not pass the I/M test.
■ When the malfunction indicator la mp still r
emains on after several
driving trips
The error code in the OBD system will not be clear
ed unless the
vehicle is driven 40 or more times.
■ If y
our vehicle does not pass the I/M test
Contact your Lexus dealer to prep ar
e the vehicle for re-testing.

418
4-3. Do-it-yourself maintenance
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 indicator on the “POWER” switch and the “READY” indicator
are both off.
●Keep hands, clothing and tools away from the moving fans 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 automati-
cally start to run if the air conditioning is on and/or the coolant temperature is high. 
(  P. 4 3 0 )
■Safety glasses
Wear safety glasses to prevent flying or falling material, fluid spray, etc. from getting
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. Also, a backfire could cause a fire in the engine compartment.

446
4-3. Do-it-yourself maintenance
■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 efficiency
●Reduced driving comfort and tire life
●Reduced safety
●Damage to the drive train
If a tire needs frequent inflating, 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 or has not been driven for
mor
e 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 misleadi ng. In
addition, tire inflation pressure
that is even just a few pounds off can affect ride quality and handling.
●Do not reduce tire inflation pressure after driving. It is normal for tire inflation
pressure to be higher after driving.
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
adjustment, apply soapy water to the v
alve and check for leak-
age.
Put the tire valve cap back on.

459
4-3. Do-it-yourself maintenance
4
Maintenance and care
10AM27. 5 A
Smart access system with push-button
start, hybrid system, multiport fuel
injection system/sequential multiport
fuel injection system, P position con-
trol system, cruise control system,
dynamic radar cruise control system
11ECU-B27. 5 A
Smart access system with push-button
start, multiport fuel injection system/
sequential multiport fuel injection sys-
tem, trunk opener switch
12MAYDAY10 ALexus link system
13ECU-B310 AAir conditioning system, rear window
defogger, mirror heater
14TURN & HAZ10 ATurn signal lights, emergency flashers
15ETCS10 A
Multiport fuel injection system/
sequential multiport fuel injection sys-
tem
16ABS MAIN NO.120 AElectronically controlled brake system
17P/I 240 A
P position control system, hybrid sys-
tem, transmission, smart access sys-
tem with push-button start, horn,
headlights (low beam), back-up lights
18ABS MTR 130 AElectronically controlled brake system
19ABS MTR 230 AElectronically controlled brake system
20H-LP HI MAIN20 AHeadlights (high beam)
21AMP NO.230 AAudio system, navigation system
22DOOR NO.225 ANo circuit
FuseAmpereCircuit

460
4-3. Do-it-yourself maintenance
23P/I 160 AIG2, EFI MAIN, BATT FAN
24EPS60 AElectric power steering system
25PCU10 AHybrid system
26IGCT NO.210 A
Smart access system with push-button
start, hybrid system, P position control
system, multiport fuel injection sys-
tem/sequential multiport fuel injection
system
27MIR HTR10 ARear window defogger, mirror heater
28RAD NO.115 AAudio system, navigation system
29DOME10 A
Interior lights, antiglare inside rear
view mirror, audio system, navigation
system, garage door opener
30ECU-B7. 5 A
Smart access system with push-button
start, air conditioning system, gauges
and meters, outside rear view mirror,
clock, seats position memory, electric
tilt & telescopic steering wheel
31H-LP LH HI10 ALeft-hand headlight (high beam)
32H-LP RH HI10 ARight-hand headlight (high beam)
33EFI NO. 210 A
Multiport fuel injection system/
sequential multiport fuel injection sys-
tem
34IGCT NO.310 AHybrid system
FuseAmpereCircuit

461
4-3. Do-it-yourself maintenance
4
Maintenance and care
35SPARE30 ASpare fuse
36SPARE10 ASpare fuse
37SPARE7. 5 ASpare fuse
38EFI MAIN20 AEFI NO.2, fuel system
39BATT FAN10 ABattery cooling fan
40IG220 A
Hybrid system, multiport fuel injec-
tion system/sequential multiport fuel
injection system, MET, IGN
FuseAmpereCircuit

462
4-3. Do-it-yourself maintenance
Driver’s side instrument panel
FuseAmpereCircuit
1TA I L10 AParking lights, tail lights, license plate
lights, side maker lights, front fog lights
2PA N E L10 A
Navigation system, audio system, air
conditioning system, emergency
flashers switch, wiper de-icer switch,
seat heater switch, P position switch,
headlight cleaner switch, front pas-
senger’s seatbelt reminder light,
power window switch, VSC-OFF
switch, HUD switch, AFS-OFF switch,
POWER ·ECO· EV mode switch,
view select switch, trunk opener
switch, fuel lid opener switch, glove
box light, rear sun shade switch,
remote touch, rear view mirror switch

463
4-3. Do-it-yourself maintenance
4
Maintenance and care
3IGN10 A
Electronically controlled brake sys-
tem, multiport fuel injection system/
sequential multiport fuel injection sys-
tem, Lexus link system, smart access
system with push-button start, stop
lights
4MET7. 5 AMeters
5WIP30 AWindshield wipers
6WA S H E R15 AWindshield washer
7A/C10 AAir conditioning system
8GAUGE10 AAFS, turn signal lights, emergency
flasher lights
9AFS10 AAdaptive front-lighting system
10ECU-IG NO.210 A
Pre-collision system, LKA, dynamic
radar cruise control, air conditioning
system, outside rear view mirror,
HUD, navigation system, tire inflation
pressure warning system
FuseAmpereCircuit