2007 Lexus GS450h cooling

404
4-3. Do-it-yourself maintenance
■Driver’s side instrument panel
FuseAmpereCircuit
1FR WIP30Windshield wipers
2RR-IG7. 5RR-IG1
3LH-IG10
Emergency flashers, seat belt preten-
sioners, headlight cleaners, exhaust
system, rear window defogger, elec-
tric cooling fans, front left door con-
trol system, rear left door control
system
4H-LP LVL7. 5Adaptive front lighting system
5A/C W/P7. 5Air conditioning system
6RAD No.310Audio system
7FR DOOR LH20Front left door control system
8RR DOOR LH20Rear left door control system
9FR S/HTR LH15Seat heaters, seat heaters and venti-
lators
10ECU-IG LH10
VGRS, EPS, electronically con-
trolled brake system, yaw rate & G
sensor, dynamic radar cruise control
system, rear view monitor system,
moon roof

474
5-2. Steps to take in an emergency
NOTICE
■To prevent damaging the vehicle
Hybrid vehicles cannot be push-started.
■When handling jumper cables
Be careful that the jumper cables do not become tangled in the cooling fan or any
of the belts when connecting or disconnecting them.

5
When trouble arises
475
5-2. Steps to take in an emergency
If your vehicle overheats
■Electric motor (traction motor) and inverter
If the message “HYBRID SYSTEM OVERHEAT” is displayed on the
multi-information display.
■ Ga
soline engine
If the needle of the engine co olant temper
ature gauge enters the
red zone, the gasoline engine has probably overheated.
Observe the following steps: Stop the vehicle in a safe place and turn of
f the automatic air
conditioning system.
Check to see if steam is coming out from under the hood.
If you see steam: 
Stop the hybrid system and carefully lift the hood.
If you do not see steam: Leave the hybrid system running and carefully lift the hood.
Remove the engine compartment cover. ( P. 362 )
Check to see if the cooling fan is operating.
If the fan is operating: 
Wait until the engine coolant temperature gauge begins to
fall and then stop the hybrid s
ystem.
If the fan is not operating: 
Stop the hybrid system immed iately and call y
our local
Lexus dealer.
After the hybrid system has
cooled do
wn sufficiently, check
the coolant level and inspect the
radiator core (radiator) for any
leaks.
STEP1
STEP2
STEP3
STEP4
STEP5

484
6-1. Specifications
Cooling system
Ignition system
Capacity
Gasoline engine
Inverter9.8 qt. (9.3 L, 8.1 lmp.qt.)
3.0 qt. (2.9 L, 2.5 lmp.qt.)
Coolant type
Use either of the following:• “Toyota Super Long Life Coolant”
• Similar high-quality ethylene glycol-based non-sili- cate, non-amine, non-nitrite, and non-borate cool-
ant with long-life organic acid technology
Do not use plain water alone.
Spark plug
Make DENSO 
NGK
GapFK20HBR11 
ILFR6D11T 
0.043 in. (1.1 mm)
NOTICE
■Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust gap when tuning engine.

511
Alphabetical index
Installing CRS with lower 
anchorages .......................................... 87
Installing CRS with seatbelts .......... 83
Installing CRS with top straps ........ 88
Child safety Airbag precautions .............................. 75
Child restraint system ........................ 80
Child-protectors.................................... 27
How your child should wear 
the seatbelt ........................................... 45
Installing child restraints .................... 83
Moon roof ................................................. 57
Power window lock switch .............. 52
Power window precautions............ 54
Removed electronic key battery 
precautions ....................................... 394
Seat belt comfort guide...................... 43
Seat belt precautions...........................46
Seat heater precautions ..... 324, 326
Trunk ............................................................ 33
Cigarette lighter .................................... 322
Cleaning Exterior ................................................... 344
Interior..................................................... 346
Seat belts ................................................ 347
Clock........................................................... 319
Coin holder .............................................. 314
Compass ................................................. 339
Condenser.............................................. 369
Console box ............................................. 312
Cooling system Engine overheating .......................... 475Cruise control
Cruise control........................................ 127
Dynamic radar cruise control....... 130
Cup holders ............................................. 315
Curtain shield airbags............................ 69
Customizable features ...................... 500
Daytime running light system ............. 121
Defogger Rear window ......................................... 199
Side mirror.............................................. 199
Dimension............................................... 480
Dinghy towing ......................................... 180
Display Energy flow ................................................. 6
Multi-informatio n display
..................117
Touch screen ........................................ 182
Trip information ..................................... 118
Warning message ............................. 436
Do-it-yourself maintenance ............. 355
Door courtesy lights ........................... 308
Door pocket............................................. 316
Doors
Door lock .................................................. 26
Rear door child protector ................ 27
Driver's seat belt reminder light ..... 433
Driving Correct posture..................................... 67
Procedures .............................................. 94
DVD player/changer.......................... 232
Electronic key Replacing battery ............................... 393
When the electronic key battery 
is discharged.................................... 469
D
E