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473
4-3. Do-it-yourself maintenance
4
Maintenance and care
HS250h_U_75050U
10P CON MAIN7. 5 A
P position control system, hybrid sys-
tem, smart access system with push-
button start
11AM27. 5 A
Smart access system with push-button
start, hybrid system, multiport fuel
injection system/sequential multiport
fuel injection system, P position con-
trol system, cruise control system,
dynamic radar cruise control system
12ECU-B27. 5 A
Smart access system with push-button
start, multiport fuel injection system/
sequential multiport fuel injection sys-
tem, trunk opener switch
13MAYDAY10 AMAYDAY
14ECU-B310 AAir conditioning system, rear window
defogger, mirror heater
15TURN & HAZ10 ATurn signal lights, emergency flashers
16ETCS10 A
Multiport fuel injection system/
sequential multiport fuel injection sys-
tem
17ABS MAIN NO.120 AElectronically controlled brake system
18P/ I 240 A
P position control system, hybrid sys-
tem, transmission, smart access sys-
tem with push-button start, horn,
headlights (low beam), back-up lights
19ABS MTR 130 AElectronically controlled brake system
20ABS MTR 230 AElectronically controlled brake system
21H-LP HI MAIN20 AHeadlights (high beam)
22AMP NO.230 AAudio system, navigation system
FuseAmpereCircuit
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4-3. Do-it-yourself maintenance
HS250h_U_75050U
23DOOR NO.225 APower door lock system
24P/ I 160 AIG2, EFI MAIN, BATT FAN
25EPS60 AElectric power steering system
26PCU10 AHybrid system
27IGCT NO.210 A
Smart access system with push-button
start, hybrid system, P position control
system, multiport fuel injection sys-
tem/sequential multiport fuel injection
system
28MIR HTR10 ARear window defogger, mirror heater
29RAD NO.115 AAudio system, navigation system
30DOME10 A
Interior lights, antiglare inside rear
view mirror, audio system, navigation
system, garage door opener
31ECU-B7. 5 A
Smart access system with push-button
start, air conditioning system, gauges
and meters, outside rear view mirror,
clock, seats position memory, electric
tilt & telescopic steering wheel
32H-LP LH HI10 ALeft-hand headlight (high beam)
33H-LP RH HI10 ARight-hand headlight (high beam)
34EFI NO. 210 A
Multiport fuel injection system/
sequential multiport fuel injection sys-
tem
35IGCT NO.310 AHybrid system
FuseAmpereCircuit
Page 477 of 630
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
FuseAmpereCircuit
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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
FuseAmpereCircuit
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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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5-2. Steps to take in an emergency
HS250h_U_75050U
■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 min-
utes).
■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. Replace the spare tire with the
repaired tire and adjust the tire inflation pressure. The tire pressure warning light
will go off after a few minutes.
■If the tire pressure warning system is not functioning
The tire pressure warning system will be disabled in the following conditions:
(When the condition becomes normal, the system will work properly.)
●If tires not equipped with tire pressure warning valves and transmitters are used.
●If the ID code on the tire pressure warning valves and transmitters is not regis-
tered in the tire pressure warning computer.
●If the tire inflation pressure is 73 psi (500 kPa, 5.1 kgf/cm2 or bar) or higher.
The tire pressure warning system may be disabled in the following conditions:
(When the condition becomes normal, the system will work properly.)
●If electronic devices or facilities using similar radio wave frequencies are nearby.
●If a radio set at similar frequency is in use in the vehicle.
●If a window tint that affects the radio wave signals is installed.
●If there is a lot of snow or ice on the vehicle, particularly around the wheels or
wheel housings.
●If non-genuine Lexus wheels are used (Even if you use Lexus wheels, the tire
pressure warning system may not work properly with some types of tires.)
●If tire chains are used.