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479
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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481
4-3. Do-it-yourself maintenance
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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483
4-3. Do-it-yourself maintenance
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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485
4-3. Do-it-yourself maintenance
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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5
When trouble arises
501
5-1. Essential information
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
If your vehicle needs to be towed
Before towingThe following may indicate a problem with your transmission. Contact
your Lexus dealer before towing.
● The hybrid system is operating, but the vehicle will not move.
● The vehicle makes an abnormal sound.
Emergency towing
If a tow truck is not available, in an emergency your vehicle may be tem-
porarily towed using a cable or chain secured to the emergency towing
eyelet. This should only be attempted on hard, surfaced roads for short
distances below 18 mph (30 km/h).
A driver must be in the vehicle to steer and operate the brakes. The vehi-
cle’s wheels, drive train, axles, steering and brakes must be in good condi-
tion.
If towing is necessary, we recommend having your vehicle towed by your
Lexus dealer or a commercial towing se rvice, using a lift-type truck or a flat
bed truck.
Use a safety chain system for all towing, and abide by all state/provincial
and local laws.
If towing from the rear, the wheels and axle on the ground must be in good
condition.
If they are damaged, use a towing dolly or flat bed truck.
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5-1. Essential information
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
Towing eyelet
■Emergency towing procedureRelease the parking brake.
Put the shift lever in “N”.
The “POWER” switch must be in the ACCESSORY mode (hybrid system
off) or the ON mode (hybrid system on).
CAUTION
■While towing
●Use extreme caution when towing the vehicle.
Avoid sudden starts or erratic driving maneuvers which place excessive stress on
the emergency towing eyelet and the cable or chain.
●If the hybrid system is off, the power assist for the brakes and steering will not
function, making steering and braking more difficult.
NOTICE
■To prevent causing serious da mage to the transmission
Never tow this vehicle from the front with the rear wheels on the ground.
This may cause serious damage to the transmission.
STEP1
STEP2
STEP3
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5
When trouble arises
507
5-1. Essential information
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably needs
adjustment or repair. Contact your Lexus dealer as soon as possible.
■Visible symptoms
● Fluid leaks under the vehicle
(Water dripping from the air conditioning after use is normal.)
● Flat-looking tires or uneven tire wear
● Engine coolant temperature gauge needle continually points
higher than normal
■ Audible symptoms
● Changes in exhaust sound
● Excessive tire squeal when cornering
● Strange noises related to the suspension system
● Pinging or other noises related to the hybrid system
■ Operational symptoms
● Engine missing, stumbling or running rough
● Appreciable loss of power
● Vehicle pulls heavily to one side when braking
● Vehicle pulls heavily to one side when driving on a level road
● Loss of brake effectiveness, sp ongy feeling, pedal almost touches
the floor
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508
5-1. Essential information
GS_HV_U (OM30B44U)
April 27, 2009 10:09 am
Event data recorder
In a crash or a near car crash eventThe SRS airbag sensor assembly contains the EDR. In a crash or a near
car crash event, this device may record some or all of the following infor-
mation:
● Gasoline engine speed
● Whether the brake pedal was applied or not
● Ve h i c l e s p e e d
● To what extent the accelerator pedal was depressed
● Position of the transmission shift lever
● Whether the driver and front passenger wore seat belts or not
● Driver’s seat position
● SRS airbag deployment data
● SRS airbag system diagnostic data
● Front passenger’s occupant classification
Your vehicle has computers that monitor and control certain aspects of
your vehicle. These computers assist in driving and maintaining optimal
vehicle performance.
Besides storing data useful for troubleshooting, there is a system to record
data in a crash or a near car crash event. This is called an Event Data
Recorder (EDR).
GS450h_HV_U.book Page 508 Monday, April 27, 2009 10:10 AM