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6-2. Maintenance
Head restraints• Do the head restraints movesmoothly and lock securely?
Indicators/buzzers• Do the indicators and buzzers func-tion properly?
Lights
• Do all the lights come on?
• Are the headlights aimed correctly? (→ P. 477)
Parking brake
• Moves smoothly?
• When parked on a slope and the
parking brake is on, is the vehicle
securely stopped?
Seat belts
• Do the seat belts operate smoothly?
• The seat belts should not be dam-aged.
Seats• Do the seat controls operate prop-erly?
Steering wheel
• Does the steering wheel rotatesmoothly?
• Does the steering wheel have the correct amount of free play?
• There should not be any strange sounds coming from the steering
wheel.
ItemsCheck points
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4376-3. Do-it-yourself maintenance
6
Maintenance and care
■Checking fluid level
The brake fluid level should be
between the “MAX” and “MIN”
lines on the tank.
■Adding fluid
Make sure to check the fluid type and prepare the necessary item.
■Brake fluid can absorb moisture from the air
Excess moisture in the brake fluid can cause a dangerous loss of braking efficiency.
Use only newly opened brake fluid.
Brake fluid
Fluid typeFMVSS No.116 DOT 3 or SAE J1703 brake fluid
Items Clean funnel
CAUTION
■When filling the reservoir
Take care as brake fluid can harm your hands and eyes and damage painted sur-
faces. If fluid gets on your hands or in your eyes, flush the affected area with clean
water immediately. If you still experience discomfort, see a doctor.
NOTICE
■If the fluid level is low or high
It is normal for the brake fluid level to go down slightly as the brake pads wear out
or when the fluid level in the accumulator is high.
If the reservoir needs frequent refilling, there may be a serious problem.
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4696-3. Do-it-yourself maintenance
6
Maintenance and care
*: Low beam and high beam are the same bulb. (vehicles with discharge headlights)
52ABS NO.130Motor relay
53ECU-B NO.27. 5No circuit
54DEICER25Windshield wiper de-icer
55ABS MAIN 310Brake system
56FILTER10Condenser
57A/C W/P7. 5Air conditioning system
58SPARE10Spare fuse
59SPARE30Spare fuse
60SPARE20Spare fuse
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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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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474
GS450h_OM_OM30F70U_(U)
6-3. Do-it-yourself maintenance
■Tr u n k
FuseAmpereCircuit
1PSB30Pre-collision seat belts
2PTL25Power trunk opener and closer
3RR J/B-B10Smart access system with push-button start
4RR S/HTR20Seat heaters (rear)
5FR S/HTR10Seat heaters/ventilators (front)
6RR FOG10No circuit
7DC/DC-S (HV)7. 5DC/DC converter
8BATT FAN (HV)20Hybrid battery (traction battery) cooling fan
system
9SECURITY7. 5SECURITY
10ECU-B NO.37. 5Pa r k i n g b r a ke
11TRK OPN7. 5Power trunk opener and closer, trunk open
motor
12DCM (HV)7. 5DCM
13AC INV (HV)20Po w e r o u t l e t ( 1 2 0 V AC )
14RR-IG15Radar sensor, Blind Spot Monitor
15RR ECU-IG10
Power trunk opener and closer, parking
brake, tension reducer (rear left-hand), RR
CTRL SW, tire pressure warning system
16EPS-IG5Electric power steering system
17BACK UP7. 5Back-up lights, Remote Touch screen
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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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7
When trouble arises
7-2. Steps to take in an emergency
If a warning light turns on or a warning buzzer
sounds
The following warning indicates a possible problem in the brake system.
Immediately stop the vehicle in a safe place and contact your Lexus
dealer.
Calmly perform the following actions if any of the warning lights comes
on or flashes. If a light comes on or flashes, but then goes off, this does
not necessarily indicate a malfunction in the system. However, if this
continues to occur, have the vehicle inspected by your Lexus dealer.
Stop the vehicle immediately. Continuing to drive the vehicle may
be dangerous.
Warning lightWarning light/Details
(U.S.A.)
(Canada)Brake system warning light (warning buzzer) • Low brake fluid
• Malfunction in the electronically controlled brake system
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