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■When to replace your vehicle’s tires
Tires should be replaced if:
●You have tire damage such as cuts, splits, cracks deep enough to expose the
fabric or bulges indicating internal damage
●A tire goes flat repeatedly or cannot be properly repaired due to the size or
location of a cut or other damage
If you are not sure, consult with your Lexus dealer.
■Replacing tires and wheels
If the ID code of the tire pressure warning valve and transmitter is not registered,
the tire pressure warning system will not work properly. After driving for about 20
minutes, the tire pressure warning light come s on after blinking for 1 minute to indi-
cate a system malfunction.
■Tire lif e
Any tire over 6 years old must be checked by a qualified technician even if they
have seldom or never been used or damage is not obvious.
■If the tread wears down below 0.16 in. (4 mm) on snow tires
The effectiveness of snow tires is lost.
■Low profile tires (245/40R18, P245/40R18 and 245/40ZR18 tires)
Generally, low profile tires will wear more rapidly and tire grip performance will be
reduced on snowy and/or icy roads when compared to standard tires. Be sure to
use snow tires or snow chains on snowy and/or icy roads and drive carefully at a
speed appropriate for road and weather conditions.
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■Initializing the tire pressure warning system
Initialize the tires with the tire inflation pressure adjusted to the specified level.
■If you push the tire pressure warning reset switch accidentally
If initialization is performed, adjust the tire inflation pressure to the specified level
and initialize the system again.
■When the initialization of the tire pressure warning system has failed
Initialization can be completed in a few minutes. However, in the following cases,
the settings have not been recorded and the system will not operate properly. If
repeated attempts to record tire inflation pressure settings are unsuccessful, have
the vehicle inspected by your Lexus dealer.
●When operating the tire pressure warning reset switch, the tire pressure warn-
ing light does not flash 3 times and the setting message does not appear on the
multi-information display.
●After carrying out the initialization procedure, the tire pressure warning light
blinks for 1 minute then stays on after driving for 20 minutes.
■Routine tire inflation pressure checks
The tire pressure warning system does not replace routine tire inflation pressure
checks. Make sure to check tire inflation pressure as part of your routine of daily
vehicle checks.
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CAUTION
■Tire pressure warning system operation
The tire pressure warning system may not provide warning immediately if a tire
bursts or if sudden air leakage occurs.
■When inspecting or replacing tires
Observe the following precautions to prevent accidents. Failure to do so may cause
damage to parts of the drive train, as well as dangerous handling characteristics,
which may lead to an accident resulting in death or serious injury.
●Do not mix tires of different makes, models or tread patterns.
Also, do not mix tires of remarkably different treadwear.
●Do not use tire sizes other than those recommended by Lexus.
●Do not mix differently constructed tires (radial, bias-belted or bias-ply tires).
●Do not mix summer, all season and winter tires.
●Do not use tires that have been used on another vehicle.
Do not use tires if you do not know how they were used previously.
■When initializing the tire pressure warning system
Do not push the tire pressure warning reset switch without first adjusting the tire
inflation pressure to the specified level. Otherwise, the tire pressure warning light
may not come on even if the tire inflation pressure is low, or it may come on when
the tire inflation pressure is actually normal.
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4-3. Do-it-yourself maintenance
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
Fuse layout and amperage ratings■ Engine compartment
FuseAmpereCircuit
1FR CTRL-B25H-LP HI, HORN
2RELIEF VLV10Fuel system
3ETCS10
Multiport fuel injection system/
sequential multiport fuel injection
system
4H-LP CLN30Headlight cleaner
5STB-AM30Active stabilizer suspension system
6DEICER25
7FR CTRL-AM30FR TAIL, FR FOG, WASH
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Maintenance and care
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
FuseAmpereCircuit
8IG210
Multiport fuel injection system/
sequential multiport fuel injection
system, noise filter
9EFI No.210Fuel system, exhaust system
10H-LP R LWR15Headlight low beam (right)
11H-LP L LWR15Headlight low beam (left)
12D/C CUT30DOME, MPX-B
13IGCT No.37. 5Hybrid battery (traction battery)
14IGCT No.27. 5Hybrid system
15MPX-B7. 5
Power windows, door control system,
power seat, electronically controlled
brake system, combination switch, tilt
and telescopic steering, gauges and
meters
16DOME7. 5Interior lights, foot lights, vanity light,
gauges and meters
17ABS MAIN110Electronically controlled brake sys-
tem
18ABS MOTOR30ABS
19ABS MAIN210Electronically controlled brake sys-
tem
20F/ P M P25Fuel system
21EFI25
EFI2, multiport fuel injection system/
sequential multiport fuel injection
system
22INJ20
Multiport fuel injection system/
sequential multiport fuel injection
system
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FuseAmpereCircuit
23A/F15Fuel system
24INV W/P10Hybrid system
25IGCT No.120Hybrid system, IGCT No.2,
IGCT No.3
26FR FOG15Fog light
27FR TAIL10Tail light, rear side marker light
28WA S H20Windshield wipers and washer
29HORN10Horn
30H-LP UPR20Headlight high beam
31DC/DC140Charging system
32RAD FAN60Electric cooling fans
33LH J/B AM80
S/ROOF, FR P/SEAT LH, TV, A/C,
FUEL OPN, FR WIP, H-LP LVL,
FR S/HTR LH, A/C W/P
34E/G AM60H-LP CLN, FR CTRL-AM, DEICER,
STB AM
35HEATER50Air conditioning system
36DEFOG50Rear window defogger
37ABS230Enhanced VSC, ABS
38RH J/B-AM80
AM1, OBD, STOP SW, TI & TE,
FR P/SEAT RH, STR LOCK,
SECURITY, ECU-IG R, RH-IG,
F S/HTR RH, CIG, PWR OUTLET,
AIR SUS
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4
Maintenance and care
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
FuseAmpereCircuit
39RR J/B80STOP LP R, STOP LP L, RR TAIL,
PSB, RR FOG, RR-IG1
40OIL PMP60Transmission
41EPS80EPS
42P/ I - B 160EFI, F/PMP, INJ
43E/G-B30EM-VLV, FR CTRL-B, ETCS
44MAIN30H-LP R LWR, H-LP L LWR
45VGRS40VGRS
46ABS150ABS MOTOR, ABS MAIN1,
ABS MAIN2
47P/ I - B 260A/F, BATT FAN, IGCT, INV W/P
48BATT FAN20Electric cooling fans
49RAD No.130Audio system
50RAD No.230Audio system
51IG2 MAIN20IG2, GAUGE, IGN
52TURN-HAZ15Front turn signal lights, rear turn
signal lights
53ABS MAIN310Electronically controlled brake sys-
tem
54ECU-B10VGRS, EPS, Lexus Link System ECU
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4-3. Do-it-yourself maintenance
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
■Left side instrument panel
FuseAmpereCircuit
1FR WIP30Windshield wipers and washers
2RR-IG7. 5RR-IG1
3LH-IG10
Emergency flashers, seat belt preten-
sioners, headlight cleaners, exhaust
system, rear window defogger, elec-
tric cooling fans, front left door con-
trol system, rear left door control
system
4H-LP LVL7. 5Adaptive front lighting system
5A/C W/P7. 5Air conditioning system
6RAD No.310Audio system
7FR DOOR LH20Front left door control system
8RR DOOR LH20Rear left door control system
9FR S/HTR LH15Seat heaters, seat heaters and venti-
lators
GS450h_HV_U.book Page 482 Monday, April 27, 2009 10:10 AM