2003 CADILLAC DEVILLE engine coolant

ENGINE COOLANT HOT, IDLE ENGINE ± 44:This
message will appear when the engine coolant
temperature is over 262ÉF (128ÉC). Stop and allow your
vehicle to idle in PARK (P) until it cools down and the
message is removed. Do not increase engine speed
above a normal idle. If it does not cool down, turn off the
engine and have it serviced before driving it again.
Severe engine damage can result from an overheated
engine. See
Engine Overheating on page 5-27.
ENGINE HOT±AC OFF ± 16:This message displays
when the engine coolant becomes hotter than the normal
operating temperature. To avoid added strain on a hot
engine, the air conditioning compressor is automatically
turned off. When the coolant temperature returns to
normal, the A/C operation will automatically resume. You
can continue to drive your vehicle. If this message
continues to appear, have the system repaired as soon
as possible to avoid compressor damage.
ENGINE OVERHEATED, STOP ENGINE ± 42:This
message will appear when the engine has overheated.
Stop and turn the engine off immediately to avoid severe
engine damage. See
Engine Overheating on page 5-27.
A multiple chime will also sound when this message is
displayed.
ENGINE POWER REDUCED ± 41:This message
informs you that the vehicle is reducing engine power
because the transaxle is being placed in gear under
conditions that may cause damage to the vehicle's
engine, transaxle or ability to accelerate.FUEL LEVEL LOW ± 11:This message serves as a
warning that the fuel level in the tank is critically
low. Stop for fuel soon. A single chime will sound when
this message is displayed.
HEADLAMPS SUGGESTED ± 23:If it's dark enough
outside and the headlamps and Twilight Sentinel
ž
controls are off, this message will display on the DIC.
This message informs the driver that turning on the
exterior lamps is recommended even though the DRL
are still illuminated. It has become dark enough outside
to require the headlamps and/or other exterior lamps.
This message will also appear if the optional
RainsenseŸ wiping feature is on and the Twilight
Sentinel
žis off.
ICE POSSIBLE ± 13:This message appears when the
outside air temperature is cold enough to create icy
road conditions.
LEFT REAR DOOR AJAR ± 142:The left rear door is
open or ajar when this message appears. The ignition
must be in ON and the transaxle not in PARK (P) for this
message to display. A chime will sound if the vehicle's
speed is greater than 3 mph (5 km/h).
OIL PRESSURE LOW STOP ENGINE ± 35:If this
message appears while the engine is running, stop the
engine and do not operate it until the cause of low oil
pressure is corrected. Severe damage to the engine can
result. A multiple chime will sound when this message is
displayed.
3-63

Service............................................................5-3
Doing Your Own Service Work.........................5-3
Adding Equipment to the Outside of Your
Vehicle......................................................5-4
Fuel................................................................5-4
Gasoline Octane............................................5-4
Gasoline Speci®cations....................................5-5
California Fuel...............................................5-5
Additives.......................................................5-6
Fuels in Foreign Countries...............................5-6
Filling Your Tank............................................5-7
Filling a Portable Fuel Container.......................5-9
Checking Things Under
the Hood....................................................5-10
Hood Release..............................................5-11
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-13
Engine Air Cleaner/Filter................................5-19
Automatic Transaxle Fluid..............................5-21
Engine Coolant.............................................5-24
Coolant Surge Tank Pressure Cap..................5-27
Engine Overheating.......................................5-27
Cooling System............................................5-30Power Steering Fluid.....................................5-36
Windshield Washer Fluid................................5-37
Brakes........................................................5-38
Battery........................................................5-41
Jump Starting...............................................5-43
Headlamp Aiming...........................................5-49
Headlamp Horizontal Aiming...........................5-50
Headlamp Vertical Aiming..............................5-50
Bulb Replacement..........................................5-53
Halogen Bulbs..............................................5-53
Headlamps..................................................5-53
Front Turn Signal, Sidemarker, Parking and
Cornering Lamps.......................................5-57
Center High-Mounted Stoplamp (CHMSL).........5-58
Taillamps, Turn Signal, and Stoplamps............5-58
Replacement Bulbs.......................................5-58
Windshield Wiper Blade Replacement..............5-59
Tires..............................................................5-60
In¯ation Ð Tire Pressure...............................5-61
Tire Pressure Monitor System.........................5-62
Tire Inspection and Rotation...........................5-64
When It Is Time for New Tires.......................5-65
Buying New Tires.........................................5-66
Section 5 Service and Appearance Care
5-1

Checking Things Under
the Hood
{CAUTION:
An electric fan under the hood can start up
and injure you even when the engine is not
running. Keep hands, clothing and tools away
from any underhood electric fan.
{CAUTION:
Things that burn can get on hot engine parts
and start a ®re. These include liquids like fuel,
oil, coolant, brake ¯uid, windshield washer and
other ¯uids, and plastic or rubber. You or
others could be burned. Be careful not to drop
or spill things that will burn onto a hot engine.
5-10

A. Windshield Washer Fluid Reservoir. SeeWindshield
Washer Fluid on page 5-37.
B. Underhood Fuse Block. See ªUnderhood Fuse
Blockº under
Fuses and Circuit Breakers on
page 5-94.
C. Engine Coolant Surge Tank and Pressure Cap. See
Coolant Surge Tank Pressure Cap on page 5-27andCooling System on page 5-30.
D. Power Steering Fluid. See
Power Steering Fluid on
page 5-36.
E. Engine Oil Fill Cap. See
Engine Oil on page 5-13.
F. Engine Oil Dipstick. See
Engine Oil on page 5-13.
G. Brake Master Cylinder. See
Brakes on page 5-38.
H. Transaxle Fluid Cap and Dipstick. See
Automatic
Transaxle Fluid on page 5-21.
I. Engine Air Cleaner/Filter. See
Engine Air
Cleaner/Filter on page 5-19.
Engine Oil
If the CHECK OIL LEVEL message appears on the
instrument cluster, it means you need to check
your engine oil level right away. For more information,
see ªCHECK OIL LEVELº under
DIC Warnings and
Messages on page 3-60.
You should check your engine oil level regularly; this is
an added reminder.
5-13

Engine Coolant
The cooling system in your vehicle is ®lled with
DEX-COOLžengine coolant. This coolant is designed
to remain in your vehicle for 5 years or 150,000 miles
(240 000 km), whichever occurs ®rst, if you add
only DEX-COOL
žextended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem
with engine overheating, see
Engine Overheating on
page 5-27.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
žcoolant will:
·Giving freezing protection down to-34É F-37É C.
·Give boiling protection up to 265É F (129É C).
·Protect against rust and corrosion.
·Help keep the proper engine temperature.
·Let the warning lights and gages work as they
should.
Notice:When adding coolant, it is important that
you use only DEX-COOLž(silicate-free) coolant.
If coolant other than DEX-COOLžis added to
the system, premature engine, heater core or
radiator corrosion may result. In addition, the engine
coolant will require change sooner Ð at 30,000 miles
(50,000 km) or 24 months, whichever occurs ®rst.
Damage caused by the use of coolant other
than DEX-COOL
žis not covered by your new vehicle
warranty.
What to Use
Use a mixture of one-halfclean, drinkable waterand
one-half DEX-COOLžcoolant which won't damage
aluminum parts. If you use this coolant mixture,
you don't need to add anything else.
5-24

{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle's coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you wouldn't get the overheat warning.
Your engine could catch ®re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
žcoolant.
Notice:If you use an improper coolant mixture, your
engine could overheat and be badly damaged. The
repair cost wouldn't be covered by your warranty.
Too much water in the mixture can freeze and crack
the engine, radiator, heater core and other parts.
If you have to add coolant more than four times a year,
have your dealer check your cooling system.
Notice:If you use the proper coolant, you don't
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.
5-25

Checking Coolant
The engine coolant surge tank is located toward the
rear of the engine compartment on the passenger's side
of the vehicle. For more information on location, see
Engine Compartment Overview on page 5-12.
{CAUTION:
Turning the surge tank pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. Never turn the surge tank pressure
cap Ð even a little Ð when the engine and
radiator are hot.
The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at the FULL
COLD mark, located on the side of the surge tank
that faces the engine.
If the CHECK COOLANT LEVEL message comes on
and stays on, it means you're low on engine coolant.
For more information see
DIC Warnings and Messages
on page 3-60.
5-26

Adding Coolant
If you need more coolant, add the proper DEX-COOLž
coolant mixtureat the surge tank,but only when the
engine is cool.
{CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol,
and it will burn if the engine parts are hot
enough. Don't spill coolant on a hot engine.
When replacing the pressure cap, make sure the arrow
lines up with the tube.
Coolant Surge Tank Pressure Cap
Notice:Your pressure cap is a pressure-type
cap and must be tightly installed to prevent coolant
loss and possible engine damage from overheating.
See ªCapacities and Speci®cationsº for more
information.
Engine Overheating
You will ®nd an ENGINE COOLANT HOT, IDLE
ENGINE message or an ENGINE OVERHEATED,
STOP ENGINE message displayed in the Driver
Information Center (DIC). You will also hear a chime.
There is also an engine temperature warning light and/or
gage on the instrument panel cluster. See
Engine
Coolant Temperature Warning Light on page 3-49andEngine Coolant Temperature Gage on page 3-50.
Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
message ENGINE OVERHEATED, STOP ENGINE is
displayed, an overheat protection mode which alternates
®ring groups of cylinders helps prevent engine damage.
In this mode, you will notice a loss in power and
engine performance. This operating mode allows your
vehicle to be driven to a safe place in an emergency;
you may drive up to 50 miles (80 km). Driving extended
miles (km) and/or towing a trailer in the overheat
protection mode should be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any repair.
The engine oil will be severely degraded. Repair the
cause of coolant loss, change the oil and reset the oil
life system. See ªEngine Oilº in the Index.
5-27