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GS450h_OM_OM30F70U_(U)
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. 4 7 7 )
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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GS450h_OM_OM30F70U_(U)
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.410Po w e r c o n t r o l u n i t
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
46FAN NO.240Electric cooling fans
47LUG J/B DC/DC80Luggage compartment junction block
48FAN NO.180Electric cooling fans
49PTC NO.150PTC heater
50PTC NO.250PTC heater
51HTR50Air conditioning system
FuseAmpereCircuit
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GS450h_OM_OM30F70U_(U)
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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GS450h_OM_OM30F70U_(U)
6-3. Do-it-yourself maintenance
■Driver’s side instrument panel
FuseAmpereCircuit
1STOP7. 5Stop lights, high mounted stoplight
2P/ W- B5Po w e r w i n d o w m a s t e r s w i t c h
3P/ S E AT 1 F/ L30Po w e r s e a t s
4D/L NO.125Power door lock system
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)
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.225Power door lock system
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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GS450h_OM_OM30F70U_(U)
6-3. Do-it-yourself maintenance
■Trunk
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. 5Parking brake
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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6-3. Do-it-yourself maintenance
■After a fuse is replaced
●If the lights do not turn on even after the fuse has been replaced, a bulb may need
replacement. (P. 4 7 9 )
●If the replaced fuse blows again, have the vehicle inspected by your Lexus dealer.
■If there is an overload in a circuit
The fuses are designed to blow, protecting the wiring harness from damage.
■When replacing light bulbs
Lexus recommends that you use genuine Lexu s products designed for this vehicle.
Because certain bulbs are connected to circuits designed to prevent overload, non-
genuine parts or parts not designed for this vehicle may be unusable.
CAUTION
■To prevent system breakdowns and vehicle fire
Observe the following precautions.
Failure to do so may cause damage to the vehicle, and possibly a fire or injury.
●Never use a fuse of a higher amperage rating than that indicated, or use any
other object in place of a fuse.
●Always use a genuine Lexus fuse or equivalent.
Never replace a fuse with a wire, even as a temporary fix.
●Do not modify the fuses or fuse boxes.
NOTICE
■Before replacing fuses
Have the cause of electrical overload determined and repaired by your Lexus
dealer as soon as possible.
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GS450h_OM_OM30F70U_(U)6-3. Do-it-yourself maintenance
6
Maintenance and care
Headlight aim
Make sure the vehicle has a full ta nk of gasoline and the area around
the headlight is not deformed.
Park the vehicle on level ground.
Sit in the driver’s seat.
Bounce the vehicle several times.
Vertical movement adjusting bolts
Discharge headlightsLED headlights
Adjustment bolt A
Adjustment bolt B
Before checking the headlight aim
1
2
1
2
3
4