2006 Lexus GX470 radiator cap

IN CASE OF AN EMERGENCY
431
IF YOUR VEHICLE OVERHEATS
If your engine coolant temperature gauge indicates
overheating, if you experience a loss of power, or if you
hear a loud knocking or pinging noise, the engine has
probably overheated.
When the engine overheats
Pull safely off the road, stop the vehicle and turn on your
emergency flashers. Put the transmission in “P” and apply the
parking brake.
A: If steam is coming from your engine:
Turn off the engine. Leave the hood closed until there is no sign
of steam or coolant. Your engine could have been seriously
damaged already. Call your Lexus dealer for assistance.
CAUTION
To help avoid personal injury, keep the hood closed until
there is no steam. Escaping steam or coolant is sign of
very high pressure.
B: If no steam is coming from your engine:
Leave the engine running and turn off the air conditioning.
Check the following.
 Is the cooling fan operating?
 Is the coolant in the acceptable range?
 Is the engine drive belt O.K.?
CAUTION
When the engine is running, keep hands and clothing
away from the moving fan and engine drive belt.
 Do not attempt to remove the radiator cap when the
engine and radiator are hot. Serious injury could
result from scalding hot fluid and steam blown out
under pressure.
If the cooling fan is not operating or the coolant is not in the
acceptable range, turn off the engine and call your Lexus
dealer.
If both conditions are O.K., after the engine coolant
temperature has cooled to normal, continue driving your
vehicle.
If the engine coolant temperature does not cool down, or your
vehicle overheats again, have it checked as soon as possible
by your Lexus dealer.

61PY009
INTRODUCTION
494
ENGINE COMPARTMENT OVERVIEW
1Engine oil level
dipstick
2Engine oil filler cap
3Brake fluid reservoir
4Fuse box
5Battery
6Condenser
7Electric cooling fan
8Radiator
9Engine coolant
reservoir
10Washer fluid tank
11Power steering fluid
reservoir

INTRODUCTION
496
DOITYOURSELF SERVICEPRECAUTIONS
If you perform maintenance yourself, be sure to follow the
correct procedure given in this Section.
You should be aware that improper or incomplete servicing
may result in operating problems.
Performing do −it−yourself maintenance during the warranty
period may affect your warranty coverage. Read the separate
Lexus Warranty statement for details and suggestions.
This Section gives instructions only for those items that are
relatively easy for an owner to perform. As explained in
Section 5, there are still a number of items that must be
performed by a qualified technician with special tools.
For information on tools and parts for do−it−yourself
maintenance, see “Parts and tools” on page 498.
Utmost care should be taken when working on your vehicle to
prevent accidental injury. Here are a few precautions that you
should be especially careful to observe:
CAUTION
 When the engine is running, keep hands, clothing,
and tools away from the moving fan and engine drive
belt. (Removing rings, watches, and ties is
advisable.)
 Right after driving, the engine compartment — the
engine, radiator, exhaust manifold and power
steering fluid reservoir, etc. — will be hot. So be
careful not to touch them. Oil, other fluids and spark
plugs may also be hot.
 If the engine is hot, do not remove the radiator cap or
loosen the drain plugs to prevent burning yourself.
 Do not leave anything that may burn easily, such as
paper or rags, in the engine compartment.
 Do not smoke, cause sparks or allow open flames
around fuel or the battery. Their fumes are
flammable.
 Do not get under your vehicle with just the body jack
supporting it. Always use automotive jack stands or
other solid supports.
 Be sure that the ignition is off if you work near the
electric cooling fan or radiator grille. With the
ignition on, the electric cooling fan will automatically
start to run if the air conditioning is on.

ENGINE
514
CHECKING THE ENGINE COOLANTLEVEL
1Reservoir cap2“F” (upper) line
3“L” (lower) line
Look at the seethrough coolant reservoir when the
engine is cold. The coolant level is satisfactory if it is
between the “F” and “L” lines on the reservoir. If the level
is low, add the coolant. (For the coolant type, see “Coolant
type selection” described below.)
The coolant level in the reservoir will vary with engine
temperature. However, if the level is on or below the “L” line,
add coolant. Bring the level up to the “F” line. If the coolant level drops within a short time after replenishing,
there
may be a leak in the system. Visually check the radiator,
hoses, engine coolant filler cap, radiator cap and drain cock
and water pump.
If you can find no leak, have your Lexus dealer test the radiator
cap pressure and check for leaks in the cooling system.
CAUTION
To prevent burning yourself, do not remove the radiator
cap when the engine is hot.