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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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472
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6-3. Do-it-yourself maintenance
■Passenger’s side instrument panel
FuseAmpereCircuit
1P/ S E AT 1 F/ R30Po w e r s e a t s
2FR P/OUTLET15Po w e r o u t l e t ( f r o n t )
3RR P/OUTLET15Po w e r o u t l e t ( r e a r )
4P/ S E AT 2 F/ R25Po w e r s e a t s
5AV S20AV S
6STRG HTR15Heated steering wheel
7WA S H20Windshield washer
8RH ECU-IG10
Navigation system, VGRS, pre-collision seat
belts, air conditioning system, brake system,
Lexus night view, yaw rate and G sensor,
capacitor, Dynamic rear steering
9RH-IG10
Tension reducer, seat heater/ventilator
switches, front right-hand door ECU, CAN
gateway ECU, tire pressure warning system,
power seats
10DOOR FR30
Front right-hand door control system (out-
side rear view mirror defoggers, power win-
dow)
11DOOR RR30Power window (rear right-hand)
12RAD NO.230Audio system
13AM27. 5Po w e r m a n a g e m e n t s y s t e m
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7-2. Steps to take in an emergency
If you think something is wrong
●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.
●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
●Engine missing, stumbling or running roughly
●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, spongy feeling, pedal almost touches the
floor
If you notice any of the following symptoms, your vehicle probably
needs adjustment or repair. Contact your Lexus dealer as soon as pos-
sible.
Visible symptoms
Audible symptoms
Operational symptoms
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5097-2. Steps to take in an emergency
GS450h_OM_OM30F70U_(U)
7
When trouble arises
■The tire pressure warning light may come on due to natural causes
The tire pressure warning light may come on due to natural causes such as natural
air leaks and tire inflation pressure changes caused by temperature. In this case,
adjusting the tire inflation pressure will turn off the warning light (after a few minutes).
■When a tire is replaced with a spare tire
The compact spare tire is not equipped with a tire pressure warning valve and trans-
mitter. If a tire goes flat, the tire pressure warning light will not turn off even though
the flat tire has been replaced with the spare tire.
■Conditions that the tire pressure warning system may not function properly
→P. 4 4 9
■If the tire pressure warning light freque ntly comes on after blinking for 1 minute
If the tire pressure warning light frequently comes on after blinking for 1 minute when
the power switch is turned to ON mode, have it checked by your Lexus dealer.
■Warning buzzer
In some cases, the buzzer may not be heard because of noisy place or an audio
sound.
■Customization
The vehicle speed linked seat belt reminder buzzer can be disabled.
(Customizable features: → P. 599)
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5337-2. Steps to take in an emergency
GS450h_OM_OM30F70U_(U)
7
When trouble arises
Carrying out the corresponding action turns the messages off.
*: For the EV drive mode operating conditions: →P. 2 0 0
Other displayed messages
Displayed messageDetailsCorrection procedure
Maintenance of the
hybrid system (traction
battery) cooling compo-
nent is required
The filter may be
clogged, the air vent
may be blocked or
there may be a gap in
the duct.
Have maintenance per-
formed on the hybrid sys-
tem (traction battery)
cooling component at
your Lexus dealer.
Indicates that the EV
drive mode is not avail-
able
*
The reason the EV
drive mode is not avail-
able (the vehicle is
idling, battery charge is
low, speed is higher
than the EV drive
mode operating speed
range, accelerator
pedal is depressed too
much) may be dis-
played.
Use the EV drive mode
when it becomes avail-
able.
Indicates that the EV
drive mode has been
automatically canceled
*
The reason the EV
drive mode is not avail-
able (the battery
charge is low, speed is
higher than the EV
drive mode operating
speed range, accelera-
tor pedal is depressed
too much) may be dis-
played.
Drive the vehicle for a
while.
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566
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7-2. Steps to take in an emergency
If your vehicle overheats
■If the needle of the engine coolant temperature gauge enters the red
zone
Stop the vehicle in a safe place and turn off the air conditioning sys-
tem, and then stop the hybrid system.
If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
After the hybrid system has cooled down sufficiently, inspect the
hoses and cooling system for leaks.
Radiator
Cooling fans
If a large amount of coolant
leaks, immediately contact your
Lexus dealer.
The following may indicate that your vehicle is overheating.
●The needle of the engine coolant temperature gauge ( →P. 91) enters
the red zone or a loss of hybrid system power is experienced. (For
example, the vehicle speed does not increase.)
●“Hybrid System Overheat” ( →P. 527) is shown on the multi-informa-
tion display.
●Steam comes out from under the hood.
Correction procedures
1
2
3
1
2
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5677-2. Steps to take in an emergency
GS450h_OM_OM30F70U_(U)
7
When trouble arises
The coolant level is satisfactory if it is between the “FULL” and
“LOW” lines on the reservoir.Reservoir
“FULL”
“LOW”
Coolant inlet cap
Add coolant if necessary.
(→ P. 569)
Water can be used in an emer-
gency if engine coolant is unavail-
able.
Start the hybrid system and turn the air conditioning system on to
check that the radiator cooling fans operate and to check for coolant
leaks from the radiator or hoses.
The fans operate when the air conditioning system is turned on immediately
after a cold start. Confirm that the fans are operating by checking the fan
sound and air flow. If it is difficult to check these, turn the air conditioning sys-
tem on and off repeatedly. (The fans may not operate in freezing tempera-
tures.)
If the fans are not operating:
Stop the hybrid system immediatel y and contact your Lexus dealer.
If the fans are operating:
Have the vehicle inspected at the nearest Lexus dealer.
4
1
2
3
4
5
6
7
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GS450h_OM_OM30F70U_(U)
8-1. Specifications
Glossary of tire terminology
Tire related termMeaning
Cold tire inflation pres-
sureTire pressure when the vehicle has been parked for
three hours or more, or has not been driven more
than 1 mile or 1.5 km under that condition
Maximum inflation pres-
sureThe maximum cold inflated pressure to which a tire
may be inflated, shown on the sidewall of the tire
Recommended inflation
pressureCold tire inflation pressure recommended by a man-
ufacturer
Accessory weight
The combined weight (in excess of those standard
items which may be replaced) of hybrid transmission,
power steering, power brakes, power windows,
power seats, radio and heater, to the extent that these
items are available as factory-installed equipment
(whether installed or not)
Curb weight
The weight of a motor vehicle with standard equip-
ment, including the maximum capacity of fuel, oil and
coolant, and if so equipped, air conditioning and
additional weight optional engine
Maximum loaded vehicle
weight
The sum of:
(a) Curb weight
(b) Accessory weight
(c) Vehicle capacity weight
(d) Production options weight
Normal occupant weight150 lb. (68 kg) times the number of occupants speci-
fied in the second column of Table 1
* that follows
Occupant distributionDistribution of occupants in a vehicle as specified in
the third column of Table 1
* below
Production options weight
The combined weight of installed regular production
options weighing over 5 lb. (2.3 kg) in excess of the
standard items which they replace, not previously
considered in curb weight or accessory weight,
including heavy duty brakes, ride levelers, roof rack,
heavy duty 12-volt battery, and special trim
RimA metal support for a tire or a tire and tube assembly
upon which the tire beads are seated
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