2003 Lexus GX470 check engine

ENGINE
413
COOLING SYSTEM
Capacity
12.9 L (13.6 qt., 11.4 lmp.qt.)
Coolant type“Toyota Genuine Long Life Coolant” or equivalent
With ethylene− glycol type coolant for a proper corrosion
protection of aluminum components
Do not use alcohol type antifreeze or plain water alone.
NOTE:
“Toyota Genuine Long Life Coolant” is filled in your Lexus vehicle. In\
order to avoid technical problems, we strongly recommen d
using “Toyota Genuine Long Life Coolant” or equivalent. Please contact your \
Lexus dealer for further details.
FUEL
Fuel type
Only UNLEADED
Octane rating87 (Research octane number 91) or higher
IGNITION SYSTEMSpark plug − Make
DENSO
NGK
− Gap
SK20R11
IFR6A11
1.1 mm (0.043 in.)
ELECTRICAL SYSTEM
Battery Open voltage at 20C (68F):
Charging rates
12.6 − 12.8 V Fully charged
12.2 − 12.4 V Half charged
11.8 − 12.0 V Discharged
[Voltage that is checked 20 minutes after the key is removed
with all the lights turned off]
5A max.

ENGINE
418
Importance of engine oil level check
One of the most important points in proper vehicle
maintenance is to keep the engine oil at the optimum level so
that oil function will not be impaired. Therefore, it is essential
that the oil level be checked regularly. Lexus recommends that
the oil level be checked every time you refuel the vehicle.
NOTICE
Failure to check the oil level regularly could lead to
serious engine trouble due to insufficient oil.
For detailed information on oil level check, see “Checking the
engine oil level” described below.
USED ENGINE OIL
CAUTION
 Used engine oil contains potentially harmful
contaminants which may cause skin disorders such
as inflammation or skin cancer, so care should be
taken to avoid prolonged and repeated contact with
it. To remove used engine oil from your skin, wash
thoroughly with soap and water.
 Dispose of used oil and used oil filters only in a safe
and acceptable manner. Do not dispose of used oil
and used oil filters in household trash, in sewers or
onto the ground. Call your Lexus dealer or a service
station for information concerning recycling or
disposal.
 Do not leave used oil within the reach of children.

ENGINE
419
CHECKING THE ENGINE OIL LEVEL
With the engine at operating temperature and turned off,
check the oil level on the dipstick.
1. To get a true reading, the vehicle should be on a level spot.
After turning off the engine, wait a few minutes for the oil to
drain back into the bottom of the engine.
2. Pull the dipstick out, hold a rag under the end and wipe it
clean.
3. Reinsert the dipstick and push it in as far as it will go, or the
reading will not be correct.
 1 Add oil2 O.K.3 Too full
4. Pull the dips tick out and look at the oil level while holding a
rag under the end. If it is between the low level mark (
4
) and
the full level mark ( 5
), it is O.K.
NOTICE
Be careful not to drop the engine oil on the vehicle
components.

ENGINE
420
If the oil level is below or only slightly above the low line,
add engine oil of the same type as already in the engine.
Remove the oil filler cap and add engine oil a little at a time,
checking the dipstick. We recommend that you use a funnel
when adding oil. The approximate quantity of oil needed to fill
between the low line and the full line on the dipstick is indicated
below for reference.
When the level reaches within the correct range, return the filler
cap and turn the cap clockwise until you hear a click.
Oil quantity. L (qt., lmp. qt.) 1.5 (1.6, 1.3)
NOTICE
 Be careful not to spill the engine oil on the vehicle
components.
 Avoid overfilling, or the engine could be damaged.
 Check the oil level on the dipstick once again after
adding the oil.
Engine oil selection
“Toyota Genuine Motor Oil” is filled in your Lexus vehicle. Use
Lexus approved “Toyota Genuine Motor Oil” or equivalent to
satisfy the following grade and viscosity.
Oil grade: API grade SL “Energy −Conserving” or ILSAC
multigrade engine oil.
Recommended viscosity: SAE 5W −30
62Z002
Outside temperature
SAE 5W30 is the best choice, for good fuel economy and
good starting in cold weather.
If SAE 5W30 oil is not available, SAE 10W30 may be
used. However, it should be replaced with SAE 5W30 at
the next oil change.

ENGINE
422
CHECKING THE ENGINE COOLANTLEVEL
 1 Reservoir cap 2 “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 ethyleneglycol type coolant for a proper
corrosion protection of aluminum components.
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.
Always use ethylene −glycol type coolant for a proper corrosion
protection of aluminum components. See information in the
next column. 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.
Coolant type selection
Use of improper coolants may damage your engine cooling
system. Your coolant must contain ethylene −glycol type
coolant for a proper corrosion protection of your engine that
contains aluminum components. We have used “Toyota
Genuine Lo ng Life Coolant” in your Lexus vehicle. In order to
avoid technical problems, we strongly recommend using
“Toyota Genuine Long Life Coolant” or equivalent.
In addition to preventing freezing and subsequent damage to
the engine, this type of coolant will also prevent corrosion.
Further supplemental inhibitors or additives are neither
needed nor recommended.
Read the coolant container for information on freeze
protection. Follow the manufacturer’s directions for how much
to mix with plain water (preferably demineralized water or
distilled water). The total capacity of the cooling system is
given on page 413.

ENGINE
423
We recommend to use 50% solution for your Lexus, to provide
protection
down to about −35C (− 31F). When it is extremely
cold, to provide protection down to about −50C (−58F), 60%
solution is recommended. Do not use more than 70% solution
for better coolant performance.
NOTICE
Do not use alcohol type antifreeze or plain water alone.
The engine cooling system is integral to maximizing
performance of your Lexus vehicle. In line with this, it is
strongly recommended that you use “Toyota Genuine Long
Life Coolant” for protecting the system, as it is an
ethylene −glycol based premium antifreeze coolant with
excellent corrosion protection properties that has been
specifically formulated for use in Lexus vehicles.
Please contact your Lexus dealer for further details of the
“Toyota Genuine Long Life Coolant” range.
CHECKING THE RADIATOR AND CONDENSER
If either of the above parts are extremely dirty or you are not
sure of their condition, take your vehicle to Lexus dealer.
CAUTION
To prevent burning yourself, be careful not to touch the
radiator or condenser when the engine is hot.
NOTICE
To prevent damage to the radiator and condenser, do
not perform the work by yourself.

CHASSIS
431
CHECKING POWER STEERINGFLUID
The power steering fluid reservoir is located under the
right side engine compartment cover. Before checking
the power steering fluid, remove the cover. (For details,
see “Removing the engine compart covers” on page 405.)
Check the fluid level, simply look at the seethrough
reservoir. If necessary, add automatic transmission fluid
DEXRON
II or III .
If the vehicle has been driven around 80 km/h (50 mph) for 20
minutes (a little more in frigid temperatures), the fluid is hot
(60 C − 80C or 140F − 175F). You may also check the level
when the fluid is cold (about room temperature, 10 C − 30C
or 50F − 85F) if the engine has not been run for about five
hours.
 1 If cold O.K.2 If cold add3 If hot O.K.
4 If hot add
Clean all dirt off the reservoir and look at the fluid level. If the
fluid is cold, the level should be in the “COLD” range. Similarly,
if it is hot, the fluid level should be in the “HOT” range. If th\
e
level is at the low side of the appropriate range, add automatic
transmission fluid DEXRON
II or III to bring the level within
the range.
To remove the reservoir cap, turn it counterclockwise and lift
up. To reinstall it, turn it clockwise. After replacing the reservoir
cap, visually check the steering box case, vane pump and hose
connections for leaks or damage.

ELECTRICAL COMPONENTS
449
NOTICE
Make sure the engine and all accessories are turned
off before performing maintenance.
 When checking the battery, remove the ground cable
first and reinstall it last.
 Be careful not to cause a short circuit with tools.
 Take care no solution gets into the battery when
washing it.
If the battery is disconnected or run down
The power windows and moon roof may not operate
automatically and the jam protection function will not function
correctly after you reconnect, replace or recharge the battery.
In any of these cases, you should normalize the power
windows and moon roof. To normalize the power windows and
moon roof, see pages 35 and 88.
Checking battery condition
Check the battery condition by the indicator color.
1BLUE − Good condition.
2WHITE − Charging necessary. Have the battery checked
by your Lexus dealer.
3RED − Have the battery checked by your Lexus dealer.
NOTICE
Do not refill the battery with water.