2007 Lexus GS350 cooling

371
4-3. Do-it-yourself maintenance
4
Maintenance and care
CAUTION
■When working near the electric cooling fan or radiator grille
Be sure the engine switch is “OFF”.
With the engine switch in “IG-ON” mode, the electric cooling fan may automati-
cally start to run if the air conditioning is on and/or the coolant temperature is high. 
(  P. 3 8 5 )
■Safety glasses
Wear safety glasses to prevent flying or fall ing material, fluid spray, etc. from getting
in the eyes.
NOTICE
■If you remove the air cleaner filter
Driving with the air cleaner filter removed may cause excessive engine wear due to
dirt in the air. Also a backfire could cause a fire in the engine compartment.

375
4-3. Do-it-yourself maintenance
4
Maintenance and care
Engine compartment
Engine oil filler cap
( P. 3 7 9 )
Engine oil level dipstick 
( P. 380)
Brake fluid reservoir (P. 386)
Fuse box ( P. 413)
Washer fluid tank 
( P. 390)Engine coolant reservoir 
( P. 384)
Electric cooling fans
Condenser ( P. 385)
Radiator ( P. 385)
Fuse box ( P. 413)
Battery ( P. 387)
GS430

376
4-3. Do-it-yourself maintenance
Engine oil level dipstick
( P. 3 7 9 )
Engine oil filler cap 
( P. 380)
Brake fluid reservoir 
( P. 386)
Fuse box ( P. 413)
Washer fluid tank 
( P. 390)Engine coolant reservoir 
( P. 384)
Electric cooling fans
Condenser ( P. 385)
Radiator ( P. 385)
Fuse box ( P. 413)
Battery ( P. 387)
GS350

383
4-3. Do-it-yourself maintenance
4
Maintenance and care
Engine coolant
The coolant level is satisfactory if it is between the “FULL” and “LOW”
lines on the reservoir when the engine is cold.
Reservoir cap
FULL
LOW
If the level is on or below the
“LOW” line, add coolant up to the
“FULL” line.
■If the coolant level drops within a short time after replenishing
Visually check the radiator, hoses, engine c ool
ant filler cap, radiator cap, drain cock
and water pump. 
If you cannot find a leak, have your Lexus dealer pressure test the cap and check for
le
aks in the cooling system.
■Coolant selection
Only use “Toyota Super Long Life Coolant” or similar hig
h quality ethylene glycol
based non-silicate, non-amine, non-nitrite, and non-borate coolant with long-life
hybrid organic acid technology.
U.S.A.: “Toyota Super Long Life Coolant” is a
mixture of 50% coolant and 50%
deionized water. (Enabled: -31 F [-35C])
Canada: “Toyota Super Long Life Coolant” is a mixture of 55% coolant and 45% de
ionized water. (Enabled: -44F [-42 C])
For more details about engine coolant, contact your Lexus dealer.

384
4-3. Do-it-yourself maintenance
Radiator and condenser
Check the radiator and condenser and clear any foreign objects. 
If either of the above parts are extremely dirty or you are not sure of their
condition, ha
ve your vehicle checked by your Lexus dealer.
CAUTION
■When the engine is hot
Do not remove the radiator cap. 
The cooling system may be under pressure and may spray hot coolant if the cap is
removed, causing burns or other injuries.
NOTICE
■When adding the coolant
Coolant is neither plain water not straight antifreeze. The correct mixture of water
and anti freeze must be used to provide proper lubrication, corrosion protection
and cooling. Be sure to read the antifreeze or coolant label.
■If you spill coolant
Be sure to wash it off with water to prevent it damage to parts or paint.
CAUTION
■When the engine is hot
Do not remove the radiator cap. The cooling system may be under pressure and
may spray hot coolant if the cap is removed, causing burns or other injuries.

418
4-3. Do-it-yourself maintenance
FuseAmpereCircuit
24RR J/B80
STOP LP R, STOP LP L, RR-B, 
RR TAIL, RR FOG, RR-IG1, PSB, 
and RR S/SHADE
25GLW PLG150Glow plug heater
26RH J/B-AM80
AM1, OBD, STOP SW, TI&TE, 
PWR OUTLET, FR P/SEAT RH, 
STR LOCK, ECU-IG RH, RH-IG, 
ACC, CIG, SECURITY, 
FR S/HER RH and AIR SUS
27ABS230VSC, ABS
28DEFOG50Rear window defogger, Noise filter
29CDS40F: CDS
30FA N 140Electric cooling fans
31HEATER50Air conditioning system
32GLW PLG250Glow plug heater
33E/G-AM60H-LMP CLN, FR CTRL-AM and 
A/C COMP
34LH J/B-AM80
S/ROOF, FR P/SEAT LH, TV, 
FR S/HTR LH, FR WIP, H-LP LVL,
LH-IG, FUEL OPEN, A/C, PANEL
and LH-B
35FA N 260

422
4-3. Do-it-yourself maintenance
FuseAmpereCircuit
9ECU-IG LH10
VSC system, ECB system, Yaw rate
and G sensor, Steering sensor,
Cruise control system, Dynamic
radar cruise control system, EPS sys-
tem, VGRS system, Rear view moni-
tor system, Four-wheel drive system,
Front controller, Moon roof, Rain sen-
sor
10FR S/HTR LH15Seat heater or Heated and ventilated
seats
11RR DOOR LH20
Rear left door control system (Power
door lock system, Door courtesy
light, Power window)
12FR DOOR LH20
Front left door control system (Power
door lock system, Power rear view
mirror control system, Door courtesy
light, Outside rear view mirror heater,
Po w e r w i n d o w )
13RAD NO.310Audio system
14H-LP LVL7. 5AFS, Automatic headlight leveling
control system
15LH-IG10
Charging system, Headlight clean-
ers, Exhaust gas sensor, Rear window
defogger, Electric cooling fans, Rear
left door control system, Front left
door control system, Emergency
flashers, Automatic transmission,
Seat belt pretensioners, Intuitive
parking assist
16FR WIP30Windshield wipers and washer

5
When trouble arises
491
5-2. Steps to take in an emergency
NOTICE
■To prevent damaging the vehicle
Do not pull- or push-start the vehicle, because the three-way catalytic converter
may overheat and become a fire hazard.
■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.