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476
4-3. Do-it-yourself maintenance
HS250h_U_75050UDriver’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 seat belt reminder light,
power window switch, VSC-OFF
switch, HUD switch, AFS-OFF switch,
POWER ·ECO MODE switch, EV
mode switch, view select switch, trunk
opener switch, fuel lid opener switch,
glove box light, rear sunshade switch,
remote touch, rear view mirror switch
Page 478 of 630
477
4-3. Do-it-yourself maintenance
4
Maintenance and care
HS250h_U_75050U
3IGN10 A
Electronically controlled brake sys-
tem, multiport fuel injection system/
sequential multiport fuel injection sys-
tem, 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
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478
4-3. Do-it-yourself maintenance
HS250h_U_75050U
11ECU-IG NO.110 A
Rear view mirror, electronically con-
trolled brake system, electric power
steering system, moon roof, rain-sens-
ing windshield wiper, emergency
flashers switch, air conditioning sys-
tem, electric head restraints, driver
monitor, steering switch, seat heaters/
ventilators, electric tilt & telescopic
steering wheel, rear sunshade, AFS
12S/ROOF30 AElectric moon roof
13DOOR RL25 ARear power window (left-side)
14DOOR RR25 ARear power window (right-side)
15SHADE RR10 ARear sunshade
16D FR DOOR25 ADriver’s side power window, outside
rear view mirror
17P FR DOOR25 APassenger’s side power window, out-
side rear view mirror
18TI & TE30 AElectric tilt & telescopic steering
wheel
19STOP10 AStop lights, electronically controlled
brake system
20A/C NO.210 ANo circuit
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479
4-3. Do-it-yourself maintenance
4
Maintenance and care
HS250h_U_75050U
21RR FOG7. 5 ANo circuit
22FUEL OPN7. 5 ATrunk opener switch, fuel filler door
opener switch
23OBD7. 5 AOn-board diagnosis
24PWR SEAT FL30 ADriver’s side power seat
25FR FOG15 AFront fog lights
26PWR SEAT FR30 APassenger’s side power seat
27PSB30 APre-collision seat belts system
28WELCAB30 ANo circuit
29DOOR NO.125 APower door lock system
30SEAT HTR FL10 ADriver’s side seat heater
31SEAT HTR FR10 APassenger’s side seat heater
32RAD NO.27. 5 A
Navigation system, audio system, air
conditioning system, HUD, remote
touch
33PWR OUTLET15 APo w e r o u t l e t
34ECU-ACC10 ARear view mirror, air conditioning sys-
tem, audio system, navigation system
FuseAmpereCircuit
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5
When trouble arises
501
5-1. Essential information
HS250h_U_75050U
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
● High engine coolant temperature warning light flashes or comes
on
■ 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, spongy feeling, pedal almost touches
the floor
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552
5-2. Steps to take in an emergency
HS250h_U_75050U
If your vehicle overheats
Correction procedures■ If the engine coolant temperature warning light comes on or flashes
Stop the vehicle in a safe place and turn off the air conditioning
system.
Check to see if steam is coming out from the engine area.
If you see steam:
Stop the hybrid system. Carefully lift the hood after the steam
subsides and then restart the hybrid system.
If you do not see steam:
Leave the hybrid system operating and carefully lift the hood.
Check to see if the cooling fans are operating.
If the fans are operating:
Wait until the high engine coolant temperature warning light goes
off and then stop the hybrid system.
If the fans are not operating:
Stop the hybrid system immediat ely and call your Lexus dealer.
The following may indicate that your vehicle is overheating:
●The high engine coolant temperature warning light comes on or
flashes:
The engine may be overheating.
● “HYBRID SYSTEM OVERHEAT” is shown on the multi-information
display:
The power control unit may be overheating.
Follow the correction procedure as described below.
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578
6-1. Specifications
HS250h_U_75050U
Warning: The temperature grades of a tire assume that it is properly inflated
and not overloaded.
Excessive speed, underinflation, or excessive loading, either separately or in
combination, can cause heat buildup and possible tire failure.
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 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
Page 612 of 630
Index
611
For vehicles with a navigation system, refer to the
“Navigation System Owner’s Manual” for information
regarding the equipment listed below.
• Navigation system
• Audio/video system
• Air conditioning
• Rear window and outside rear view mirror defogging
• Windshield wiper de-icer
•Climate control
• Rear view monitor system
• Wide view front monitor system
• Intuitive parking assist
HS250h_U_75050U
Abbreviation list ..................... 612
Alphabetical index .................. 614
What to do if... ....................... 625