2008 Lexus GX470 cooling

319
4-3. Do-it-yourself maintenance
4
Maintenance and care
CAUTION
The engine compartment contains many mechanisms and fluids that may move sud-
denly, become hot, or become electrically energized. To avoid death or serious injury.
■When working on the engine compartment
●Keep hands, clothing, and tools away from the moving fan and engine drive belt.
●Be careful not to touch the engine, inverter, radiator, exhaust manifold, etc. right
after driving as they may be hot. Oil and other fluids may also be hot.
●Do not leave anything that may burn easily, such as paper or rags, in the engine
compartment.
●Do not smoke, cause sparks or expose an open flame to fuel or the battery. Fuel
and battery fumes are flammable.
●Be extremely cautious when working on the battery. It contains poisonous and
corrosive sulfuric acid.
■When working near the electric cooling fan or radiator grille
Be sure the engine switch is in “LOCK”.
With the engine switch is in the “ACC” or “ON” position, the electric cooling fan
may automatically start to run if the air conditioning is on and/or the coolant tem-
perature is high. (→P. 3 2 9 )
■Safety glasses
Wear safety glasses to prevent flying or falling 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.

321
4-3. Do-it-yourself maintenance
4
Maintenance and care
Engine compartment
Engine oil level dipstick(→P. 323)
Engine oil filler cap (→P. 324)
Brake fluid reservoir (→P. 3 3 0 )
Fuse box ( →P. 355)
Battery ( →P. 333)Condenser ( →P. 329)
Electric cooling fan
Engine coolant reservoir (→P. 328)
Radiator ( →P. 329)
Washer fluid tank ( →P. 335)
Power steering fluid reservoir (→P. 3 3 1 )

328
4-3. Do-it-yourself maintenance
Engine coolantThe coolant level is satisfactory if it is between the “F” and “L” lines on the
reservoir when the engine is cold. Reservoir cap
Full
Low
If the level is on or below the “L”
line, add coolant up to the “F” line.
■If the coolant level drops within a short time after replenishing
Visually check the radiator, hoses, reservoir 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
leaks in the cooling system.
■Coolant selection
Only use “Toyota Super Long Life Coolant” or similar high 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% deionized water. (Enabled: -44 °F [-42 °C])
For more details about engine coolant, contact your Lexus dealer.

329
4-3. Do-it-yourself maintenance
4
Maintenance and care
Radiator and condenserCheck 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, have 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 nor straight antifreeze. The correct mixture of water
and antifreeze 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
■The radiator and condenser may be hot after driving
To prevent burns, do not touch the radiator or condenser after driving.

358
4-3. Do-it-yourself maintenance
FuseAmpereCircuit
8TOW I NG40Tr a i l e r l i g h t s
9CDS FAN20Electric cooling fan
10RR A/C30Rear air conditioning system
11MIR HEATER10Outside rear view mirror defogger
12STOP10
Stop lights, high mounted stoplight,
shift lock control system, vehicle sta-
bility control system, electronic mod-
ulated suspension, rear height control
air suspension, multiport fuel injec-
tion system/sequential multiport fuel
injection system
13AC INV15Power outlet (115V AC)
14FR FOG15Front fog lights
15OBD7. 5On-board diagnosis system
16HEAD (LO RH)10Right hand headlight (low beam)
17HEAD (LO LH)10Left hand headlight (low beam)
18HEAD (HI RH)10Right hand headlight (high beam)
19HEAD (HI LH)10Left hand headlight (high beam)
20EFI NO.210
Multiport fuel injection system/
sequential multiport fuel injection
system
21HEATER No.27. 5Air conditioning system
22DEFOG30Rear window defogger
23AIRSUS NO.210Rear height control air suspension
24S E AT H E AT E R20Seat heaters

5
When trouble arises
407
5-2. Steps to take in an emergency
CAUTION
■Battery precautions
The battery contains poisonous and corrosive acidic electrolyte, while related parts
contain lead and lead compounds. Observe the following precautions when han-
dling the battery:
●When working with the battery, always wear safety glasses and take care not to
allow any battery fluids (acid) to come into contact with skin, clothing or the vehi-
cle body.
●Do not lean over the battery.
●If the battery fluid comes into contact with the skin or eyes, immediately wash the
affected area with water and seek medical attention.
Place a wet sponge or cloth over the affected area until medical attention can be
received.
●Always wash your hands after handling the battery support, terminals, and other
battery-related parts.
●Do not allow children near the battery.
NOTICE
■To avoid damaging the vehicle
Do not pull or push-start the vehicle, as the three-way catalytic converter may over-
heat 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.

408
5-2. Steps to take in an emergency
If your vehicle overheats
If the engine overheats:
Stop the vehicle in a safe place and turn off the automatic air
conditioning system.
Check to see if steam is coming out from under the hood.
If you see steam: Turn off the engine and carefully lift the hood.
If you do not see steam: Leave the engine running and carefully lift the hood.
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 engine.
If the fan is not operating: Stop the engine immediately and call your local Lexus
dealer.
After the engine has cooled
down sufficiently, check the
coolant level and inspect the
radiator for any leaks.STEP1
STEP2
STEP3
STEP4

416
6-1. Specifications
Cooling system
Ignition system
Capacity13.6 qt. (12.9 L, 11.4 Imp.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 hybrid organic acid technology
Do not use plain water alone.
Spark plug
Make DENSO
NGKSK20R11
IFR6A11
Gap0.043 in. (1.1 mm)
NOTICE
■Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust the gap when tuning the engine.