2005 CADILLAC DEVILLE engine overheat

If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. In heavy traffic, let the engine idle in NEUTRAL (N)
while stopped. If it safe to do so, pull off the road,
shift to PARK (P) or NEUTRAL (N) and let the
engine idle.
2. Set the climate controls to the highest heat setting
and fan speed and open the windows as necessary.
If you no longer have the overheat warning, you
can drive. Just to be safe, drive slower for about
10 minutes. If the warning does not come back on, you
can drive normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there is still no sign of steam, idle the engine for three
minutes while you are parked. If you still have the
warning,turn off the engine and get everyone out of the
vehicleuntil it cools down. Also, see “Overheated
Engine Protection Operating Mode” later in this section.
You may decide not to lift the hood but to get service
help right away.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.
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. SeeEngine Oil on
page 5-14.
5-29

{CAUTION:
Heater and radiator hoses, and other engine
parts, can be very hot. Do not touch them. If
you do, you can be burned.
Do not run the engine if there is a leak. If you
run the engine, it could lose all coolant. That
could cause an engine re, and you could be
burned. Get any leak xed before you drive the
vehicle.
If there seems to be no leak, with the engine on, check
to see if the electric engine cooling fans are running.
If the engine is overheating, both fans should be
running. If they are not, your vehicle needs service.Notice:Engine damage from running your engine
without coolant is not covered by your warranty. See
Overheated Engine Protection Operating Mode on
page 5-29for information on driving to a safe place
in an emergency.
Notice:Using coolant other than DEX-COOL®may
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
5-31

{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 would not 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
®coolant.Notice:In cold weather, water can freeze and crack
the engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.
{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. Do not spill coolant on a hot engine.
5-33

Electrical System (cont.)
Headlamp Wiring.........................................5-97
Power Windows and Other Power Options.........5-97
Rear Underseat Fuse Block.........................5-101
Underhood Fuse Block.................................5-98
Windshield Wiper Fuses...............................5-97
Engine
Air Cleaner/Filter.........................................5-19
Battery.......................................................5-40
Check and Service Engine Soon Light............3-50
Coolant......................................................5-24
Coolant Heater............................................2-27
Coolant Temperature Gage...........................3-49
Coolant Temperature Warning Light................3-49
Engine Compartment Overview......................5-12
Exhaust.....................................................2-35
Oil .............................................................5-14
Oil Life System...........................................5-17
Overheated Protection Operating Mode...........5-29
Overheating................................................5-27
Speed Limiter.............................................3-44
Starting......................................................2-26
Entry Lighting.................................................3-21
Event Data Recorders (EDR)............................. 7-9
Extender, Safety Belt.......................................1-27
Exterior Lamps...............................................3-15
Exterior Lighting Battery Saver..........................3-20F
Filter
Engine Air Cleaner......................................5-19
Finish Damage...............................................5-94
Flash-to-Pass................................................... 3-9
Flat Tire........................................................5-76
Flat Tire, Changing.........................................5-77
Flat Tire, Storing.............................................5-85
Fluid
Automatic Transaxle.....................................5-21
Power Steering...........................................5-35
Windshield Washer......................................5-36
Fog Lamp Light..............................................3-54
Fog Lamps....................................................3-18
Front Storage Area.........................................2-49
Fuel............................................................... 5-5
Additives...................................................... 5-6
California Fuel.............................................. 5-5
Data Display...............................................3-56
Filling a Portable Fuel Container....................5-10
Filling Your Tank........................................... 5-7
Fuels in Foreign Countries.............................. 5-6
Gage.........................................................3-55
Gasoline Octane........................................... 5-5
Gasoline Specications.................................. 5-5
Full Floor Console Storage Area.......................2-49
5

N
Navigation/Radio System, see Navigation
Manual......................................................3-99
New Vehicle Break-In......................................2-24
Night Vision System........................................3-22
Normal Maintenance Replacement Parts............6-13
O
Odometer......................................................3-43
Odometer, Trip...............................................3-43
Off-Road Recovery..........................................4-12
Oil
Engine.......................................................5-14
Life Indicator...............................................3-79
Pressure Light.............................................3-53
Oil, Engine Oil Life System..............................5-17
Older Children, Restraints................................1-28
Online Owner Center........................................ 7-3
OnStar
®System, see OnStar®Manual...............2-42
Other Warning Devices...................................... 3-6
Outlet Adjustment............................................3-34
Outside
Automatic Dimming Mirror.............................2-41
Convex Mirror.............................................2-41
Curb View Assist Mirror................................2-41
Heated Mirrors............................................2-41
Power Mirrors.............................................2-40Overheated Engine Protection
Operating Mode..........................................5-29
Owner Checks and Services.............................. 6-9
Owners, Canadian............................................... ii
P
Parade Dimming.............................................3-21
Park Aid........................................................3-26
Park (P)
Shifting Into................................................2-32
Shifting Out of............................................2-34
Parking
Assist........................................................3-26
Brake........................................................2-31
Brake Indicator Light....................................3-47
Over Things That Burn.................................2-35
Passenger Compartment Air Filter.....................3-36
Passing.........................................................4-13
PASS-Key
®III ................................................2-21
PASS-Key®III Operation..................................2-22
Performance Shifting.......................................2-31
Personalization, Climate Controls......................3-39
Power
Accessory Outlets........................................3-28
Door Locks.................................................2-10
Electrical System.........................................5-97
Inadvertent Battery Saver.............................3-22
9