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4516-3. Do-it-yourself maintenance
6
Maintenance and care
CAUTION
■When inspecting or replacing tires
Observe the following precautions to prevent accidents.
Failure to do so may cause damage to parts of the drive train as well as dangerous
handling characteristics, which may lead to an accident resulting in death or seri-
ous injury.
●Do not mix tires of different makes, models or tread patterns.
Also, do not mix tires of remarkably different treadwear.
●Do not use tire sizes other than those recommended by Lexus.
●Do not mix differently constructed tires (radial, bias-belted or bias-ply tires).
●Do not mix summer, all season and snow tires.
●Do not use tires that have been used on another vehicle.
Do not use tires if you do not know how they were used previously.
■When initializing the tire pressure warning system
Do not operate the tire pressure warning reset switch without first adjusting the tire
inflation pressure to the specified level. Otherwise, the tire pressure warning light
may not come on even if the tire inflation pressure is low, or it may come on when
the tire inflation pressure is actually normal.
■Caution regarding interference with electronic devices (vehicles with the tire
inflation pressure display function)
●Users of any electrical medical device other than implantable cardiac pacemak-
ers, cardiac resynchronization therapy-pacemakers or implantable cardioverter
defibrillators should consult the manufacturer of the device for information about
its operation under the influence of radio waves.
Radio waves could have unexpected effects on the operation of such medical
devices.
●People with implantable cardiac pacemak-
ers, cardiac resynchronization therapy-
pacemakers or implantable cardioverter
defibrillators should not come within 17.7 in.
(450 mm) of the tire pressure warning sys-
tem initiators. The radio waves may affect
the operation of such devices.
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6-3. Do-it-yourself maintenance
34DOME7. 5
Personal lights, ornament lights, trunk light,
footwell lights, door courtesy lights, vanity
lights, rear door inside handle illuminations,
power trunk opener and closer
35MPX-B10
Body ECU, smart access system with push-
button start, electric tilt and telescopic steer-
ing column, power seats, head-up display,
front door ECU, gauges and meters, steer-
ing sensor, yaw rate and G sensor, overhead
module, RR CTRL SW, power trunk opener
and closer, clock, CAN gateway ECU
36IGCT NO.410Power control unit
37IGCT NO.37. 5Hybrid battery (traction battery), DC/DC
converter
38IGCT NO.25Hybrid system
39IG2 NO.15DCM, CAN gateway ECU
40GAUGE5Gauges and meters
41DC/DC150RH-J/B DC/DC, P/I DC/DC,
LH-J/B DC/DC, LUG-J/B DC/DC
42P/ I D C / D C100RR S/SHADE, DEFOG, FOG, TAIL,
PA N E L
43RH J/B DC/DC80Right-hand junction block
44LH J/B DC/DC50Left-hand junction block
45H-LP CLN30No circuit
46FA N N O. 240Electric cooling fans
47LUG J/B DC/DC80Luggage compartment junction block
48FA N N O.180Electric cooling fans
49PTC NO.150PTC heater
50PTC NO.250PTC heater
51HTR50Air conditioning system
FuseAmpereCircuit
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6-3. Do-it-yourself maintenance
■Driver’s side instrument panel
FuseAmpereCircuit
1STOP7. 5Stop lights, high mounted stoplight
2P/ W- B5Power window master switch
3P/ S E AT 1 F/ L30Po w e r s e a t s
4D/L NO.125Po w e r d o o r l o c k s y s t e m
5NV-IR10Lexus night view
6FL S/HTR10Seat heaters/ventilators
7WIPER30Windshield wipers
8WIPER-IG5Windshield wipers
9LH-IG10
Seat belts, body ECU, AFS, overhead mod-
ule, raindrop sensor, inside rear view mirror,
lane camera sensor (LKA), head-up display,
shift lock system, intuitive parking assist, front
left-hand door ECU, driver monitor system,
Remote Touch screen, electric tilt and tele-
scopic steering column, power seats, moon
roof, windshield wiper de-icer, intuitive park-
ing assist switch, PTC heater, Blind Spot
Monitor buzzer
10LH ECU-IG10
VDIM, brake system, D-SW MODULE
(Blind Spot Monitor, heated steering wheel),
driver support system, AFS, electric cooling
fans, EPB, air conditioning system, steering
sensor
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GS450h_OM_OM30F70U_(U)
4736-3. Do-it-yourself maintenance
6
Maintenance and care
14MULTIMEDIA10Navigation system, Remote Touch
15RAD NO.130Audio system
16AIR BAG10SRS airbag system, occupant classification
system
17OBD7. 5On-board diagnosis system
18ACC7. 5
Body ECU, DCM, head-up display, RR
CTRL, Remote Touch screen, navigation sys-
tem, clock, transmission
FuseAmpereCircuit
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7When trouble arises
7-1. Essential information Emergency flashers................... 494
If your vehicle has to be stopped in an emergency ....495 7-2. Steps to take in an emergency
If your vehicle needs to be towed ................................ 496
If you think something is wrong ................502
If a warning light turns on or a warning buzzer sounds .....503
If a warning message is displayed ................................. 513
If you have a flat tire.................... 541
If the hybrid system will not start................................ 554
If the shift lever cannot be shifted from P ..................... 556
If the parking brake cannot be released ................................ 557
If the electronic key does not operate properly ..................... 559
If the 12-volt battery is discharged ............................. 562
If your vehicle overheats ......... 566
If the vehicle becomes stuck ...............................................571
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496
GS450h_OM_OM30F70U_(U)
7-2. Steps to take in an emergency
If your vehicle needs to be towed
The following may indicate a problem with your transmission. Contact
your Lexus dealer or commercial towing service before towing.
●The hybrid warning message shows on the multi-information display
and the vehicle does not move.
●The vehicle makes an abnormal sound.
If towing is necessary, we recommend having your vehicle towed by
your Lexus dealer or commercial towing service, using a wheel-lift type
truck or flatbed truck.
Use a safety chain system for all towing, and abide by all state/provin-
cial and local laws.
Situations when it is necessary to contact dealers before towing
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7
When trouble arises
7-2. Steps to take in an emergency
If a warning message is displayed
Master warning light
The master warning light also comes
on or flashes in order to indicate that a
message is currently being displayed
on the multi-information display.
Multi-information display
If any of the warning light comes on again after the following actions have
been performed, contact your Lexus dealer.
The following warning indicates a possible problem in the brake system.
Immediately stop the vehicle in a safe place and contact your Lexus
dealer.
If a warning is shown on the multi-information display, stay calm and
perform the following actions:
1
2
Stop the vehicle immediately. Continuing to drive the vehicle may
be dangerous.
Warning messageDetails
Indicates the following: • The brake fluid level is low; or,
• The brake system is malfunctioning.A buzzer also sounds.
(U.S.A.)
(Canada)
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5147-2. Steps to take in an emergency
GS450h_OM_OM30F70U_(U)A buzzer sounds and a warning message is shown on the multi-informa-
tion display. The following warning indicates the possibility of damage to
the vehicle that may lead to an accide
nt. Immediately stop the vehicle in a
safe place and contact your Lexus dealer.
Indicates a malfunction in: • The regenerative brake system;
• The electronically controlled brake system; or
• The electric parking brakeA buzzer also sounds.
Stop the vehicle immediately.
Warning messageDetails
Warning messageDetails
Indicates abnormal engine oil pressureThe warning light may come on if the engine oil
pressure is too low.
Indicates a malfunction in the hybrid system
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