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4-3. Do-it-yourself maintenance
4
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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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
Maintenance and care
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
FuseAmpereCircuit
10ECU-IG LH10
VGRS, EPS, electronically con-
trolled brake system, yaw rate & G
sensor, dynamic radar cruise control
system, rear view monitor system,
moon roof
11PA N E L7. 5
Steering switches, distance control
switch, audio system, glove box light,
switch illumination, cigarette lighter,
shift lever light, touch screen, rear
personal lights
12S/ROOF25Moon roof
13FUEL OPEN10Fuel lid opener
14LH-B10Theft deterrent system
15TRK OPN10Tr u n k o p e n e r
16TV7. 5Touch screen, rear view monitor sys-
tem
17A/C7. 5Air conditioning system
18FR P/SEAT LH30Po w e r s e a t
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4
Maintenance and care
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
FuseAmpereCircuit
7AIR SUS20AV S
8PWR OUTLET15Po w e r o u t l e t
9CIG15Cigarette lighter
10ACC7. 5
Audio system, smart access system
with push-button start, touch screen,
rear view monitor system, Lexus Link
System ECU
11IGN10
Smart access system with push-but-
ton start, SRS airbag system, stop-
lights, hybrid system, steering lock
system, electronically controlled
brake system, Lexus Link System
ECU, front passenger occupant clas-
sification system ECU
12GAUGE7. 5Gauges and meters
13STR LOCK25Steering lock system
14SECURITY7. 5Smart access system with push-but-
ton start
15TI & TE20Tilt and telescopic steering
16AM17. 5
17STOP SW7. 5Stoplights, shift lock system
18OBD7. 5On-board diagnosis system
19FR P/SEAT RH30Po w e r s e a t
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April 27, 2009 10:09 am
5-2. Steps to take in an emergency
If a warning light turns on or a warning buzzer sounds...
Stop the vehicle immediately. Continuing to drive the vehicle may be
dangerous.
The following warning indicates a possible problem in the brake system.
Immediately stop the vehicle in a safe place and contact your Lexus
dealer.
*1: Parking brake engaged warning buzzer:
→ P. 5 2 5
Stop the vehicl e immediately.
The following warning indicates the possibility of damage to the vehicle
that may lead to an accident. Immediately stop the vehicle in a safe place
and contact your Lexus dealer.
Warning lightWarning light/Details
(U.S.A.)
(Canada)
Brake system warning light (warning buzzer) *1
•Low brake fluid
• Malfunction in the brake system
This light also comes on when the parking brake is not
released. If the light turns off after the parking brake is fully
released, the system is operating normally.
Warning lightWarning light/Details
Charging system warning lightMalfunction in the vehicle’s charging system.
Calmly perform the following actions if any of the warning lights turn on or
flash. If a light turns on or flashes, but then turns off, this does not necessar-
ily indicate a malfunction in the system.
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When trouble arises
511
5-2. Steps to take in an emergency
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
Have the vehicle inspected immediately.
Failure to investigate the cause of the following warnings may lead to the
system operating abnormally and possibly cause an accident. Have the
vehicle inspected by your Lexus dealer immediately.
Warning lightWarning light/Details
(U.S.A.)
(Canada)
Malfunction indicator lamp Malfunction in:
• The emission control system;
• The electronic engine control system;
• The hybrid system;
• The electronic throttle control system; or
• The transmission control system.
SRS warning light
Malfunction in:
• The SRS airbag system;
• The front passenger occupant classification system; or
• The seat belt pretensioner system.
(U.S.A.)
(Canada)
ABS warning lightMalfunction in:
•The ABS; or
• The brake assist system.
ECB (Electronically controlled brake system) warning light Malfunction in the electronically controlled brake system.
Electric power steering system warning light
Malfunction in the EPS.
“PCS” warning light (if equipped)Malfunction in the pre-collision system.
Slip indicatorMalfunction in the Enhanced VSC.
The indicator will blink when Enhanced VSC, TRAC or hill-
start assist control is operational. ( →P. 2 1 5 )
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5-2. Steps to take in an emergency
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
■If the tire pressure warning light comes on after blinking for 1 minute frequently
If the tire pressure warning light comes on after blinking for 1 minute frequently
when the “POWER” switch is turned to ON mode, have it checked by your Lexus
dealer.
CAUTION
■If the tire pressure warning light comes on
Be sure to observe the following precautions. Failure to do so could cause loss of
vehicle control and result in death or serious injury.
●Vehicles with standard tires:
• Stop your vehicle in a safe place as soon as possible. Adjust the tire inflationpressure immediately.
• If the tire pressure warning light comes on even after tire inflation pressure
adjustment, it is probable that you have a flat tire. Check the tires. If the tire is
flat, change to the spare tire and have the flat tire repaired by the nearest
Lexus dealer.
• Avoid abrupt maneuvering and braking. If the vehicle tires deteriorate, you could lose control of the steering wheel or the brakes.
●Vehicles with run-flat tires:
• Decelerate to the lowest appropriate speed as soon as possible. Do not drive
over 55 mph (90 km/h).
• Check and adjust the tire inflation pressure immediately.
• If the tire pressure warning light comes on even after tire inflation pressure adjustment, it is probable that you have a flat tire. Have the tire replaced by
the nearest Lexus dealer.
• Avoid abrupt maneuvering and braking. If the vehicle tires deteriorate, you
could lose control of the steering wheel or the brakes.
■If a blowout or sudden air leakage should occur
The tire pressure warning system may not activate immediately.
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Abbreviation list
Abbreviation/Acronym list
ABBREVIATIONSMEANING
A/CAir Conditioning
ABSAnti-Lock Brake System
AFSAdaptive Front-lighting System
ALRAutomatic Locking Retractor
CRSChild Restraint System
DISPDisplay
ECUElectronic Control Unit
EDREvent Data Recorder
ELREmergency Locking Retractor
Enhanced VSCEnhanced Vehicle Stability Control
EPSElectric Power Steering
GAWRGross Axle Weight Ratings
GPSGlobal Positioning System
I/MEmission inspection and maintenance
INFOInformation
LEDLight Emitting Diode
LATCHLower Anchors and Tethers for Children
MMTMethylcy clopentadienyl Manganese Tricarbonyl
M + SMud and Snow
MTBEMethyl Tertiary Butyl Ether
OBDOn Board Diagnostics
GS450h_HV_U.book Page 602 Monday, April 27, 2009 10:10 AM