2005 BUICK CENTURY coolant temperature

Engine Coolant Heater
Your vehicle may be equipped with this feature. In very
cold weather, 0°F (−18°C) or colder, the engine coolant
heater can help. You will get easier starting and better
fuel economy during engine warm-up. Usually, the
coolant heater should be plugged in a minimum of four
hours prior to starting your vehicle. At temperatures
above 32°F (0°C), use of the coolant heater is
not required.
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord.
The cord is attached to the underside of the
diagonal brace, which is located above the engine
air cleaner/lter assembly.
3. Plug it into a normal, grounded 110-volt AC outlet.
{CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the
wrong kind of extension cord could overheat
and cause a re. You could be seriously
injured. Plug the cord into a properly grounded
three-prong 110-volt AC outlet. If the cord will
not reach, use a heavy-duty three-prong
extension cord rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and
store the cord as it was before to keep it away
from moving engine parts. If you do not, it could
be damaged.
How long should you keep the coolant heater plugged
in? The answer depends on the outside temperature, the
kind of oil you have, and some other things. Instead
of trying to list everything here, we ask that you contact
your dealer in the area where you will be parking
your vehicle. The dealer can give you the best advice
for that particular area.
2-20

Instrument Panel Overview...............................3-4
Hazard Warning Flashers................................3-6
Other Warning Devices...................................3-6
Horn.............................................................3-6
Tilt Wheel.....................................................3-6
Turn Signal/Multifunction Lever.........................3-7
Turn and Lane-Change Signals........................3-7
Headlamp High/Low-Beam Changer..................3-8
Flash-to-Pass.................................................3-8
Windshield Wipers..........................................3-8
Windshield Washer.........................................3-9
Cruise Control..............................................3-10
Exterior Lamps.............................................3-13
Headlamps on Reminder................................3-13
Delayed Headlamps......................................3-13
Daytime Running Lamps/Automatic
Headlamp System.....................................3-14
Cornering Lamps..........................................3-15
Interior Lamps..............................................3-15
Instrument Panel Brightness...........................3-15
Courtesy Lamps...........................................3-15
Dome Lamp.................................................3-16
Entry Lighting...............................................3-16
Delayed Entry Lighting...................................3-16Delayed Exit Lighting.....................................3-17
Reading Lamps............................................3-17
Battery Run-Down Protection..........................3-17
Ashtrays and Cigarette Lighter........................3-18
Climate Controls............................................3-18
Dual Climate Control System..........................3-18
Dual Automatic Climate Control System...........3-21
Outlet Adjustment.........................................3-26
Passenger Compartment Air Filter...................3-26
Warning Lights, Gages, and Indicators............3-28
Instrument Panel Cluster................................3-29
Speedometer and Odometer...........................3-30
Trip Odometer..............................................3-30
Safety Belt Reminder Light.............................3-30
Airbag Readiness Light..................................3-31
Charging System Light..................................3-32
Brake System Warning Light..........................3-32
Anti-Lock Brake System Warning Light.............3-33
Enhanced Traction System Warning Light.........3-34
Low Traction Light........................................3-34
Engine Coolant Temperature Warning Light......3-35
Engine Coolant Temperature Gage..................3-35
Tire Pressure Light.......................................3-36
Section 3 Instrument Panel
3-1

Engine Coolant Temperature
Warning Light
This light indicates that
the engine coolant has
overheated or the radiator
cooling fan is not working.
The light will come on briey when the ignition is turned
on to show that it is working.
If the vehicle has been operating under normal driving
conditions, pull off the road, stop the vehicle and turn off
the engine as soon as possible. SeeEngine Overheating
on page 5-25.
Engine Coolant Temperature Gage
The vehicle has a gage
that shows the engine
coolant temperature. If the
gage pointer moves into
the red area, the engine
is too hot.
This reading indicates the same thing as the warning
light. It means that the engine coolant has overheated.
If the vehicle has been operating under normal
driving conditions, pull off the road, stop the vehicle and
turn off the engine as soon as possible. SeeEngine
Overheating on page 5-25.
3-35

Engine Coolant
The cooling system in the vehicle is lled with
DEX-COOL®engine coolant. This coolant is designed
to remain in the vehicle for 5 years or 150,000 miles
(240 000 km), whichever occurs rst, if only
DEX-COOL
®extended life coolant is added.
The following explains the cooling system and how to
add coolant when it is low. If there is a problem
with engine overheating or if coolant needs to be added
to the radiator, seeEngine Overheating on page 5-25.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
Give freezing protection down to−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
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.
What to Use
Use a mixture of one-half clean, drinkable water and
one-half DEX-COOL®coolant which will not damage
aluminum parts. If this coolant mixture is used, nothing
else needs to be added.
{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.
5-22

Engine Overheating
The coolant temperature gage and the engine coolant
temperature warning light on the instrument panel
can indicate an overheated engine condition.
SeeEngine Coolant Temperature Gage on page 3-35
andEngine Coolant Temperature Warning Light on
page 3-35.
If Steam Is Coming From Your Engine
{CAUTION:
Steam from an overheated engine can burn
you badly, even if you just open the hood.
Stay away from the engine if you see or hear
steam coming from it. Just turn it off and get
everyone away from the vehicle until it cools
down. Wait until there is no sign of steam or
coolant before you open the hood.
CAUTION: (Continued)
CAUTION: (Continued)
If you keep driving when your engine is
overheated, the liquids in it can catch re.
You or others could be badly burned. Stop
your engine if it overheats, and get out of the
vehicle until the engine is cool.
See “Overheated Engine Protection Operating
Mode” underEngine Overheating on page 5-25
for information on driving to a safe place in
an emergency.
Notice:If your engine catches re because you
keep driving with no coolant, your vehicle can
be badly damaged. The costly repairs would not
be covered by your warranty. See “Overheated
Engine Protection Operating Mode” underEngine
Overheating on page 5-25for information on driving
to a safe place in an emergency.
5-25

If No Steam Is Coming From
Your Engine
An overheated engine warning can indicate a
serious problem.
If there is an overheated engine warning and you do not
see or hear any steam, the problem may not be too
serious. Sometimes the engine can get a little too hot
when the vehicle:
Climbs a long hill on a hot day.
Stops after high-speed driving.
Idles for long periods in traffic.
Tows a trailer.
If an overheated engine warning appears 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 is safe to do so, pull off the road,
shift to PARK (P) or NEUTRAL (N) and let the
engine idle.
2. Adjust the heater to the highest temperature and fan
speed settings and open the window as necessary.
If the overheated engine warnings no longer exist,
you can drive. Just to be safe, drive slower for about
10 minutes. If the warnings do not come back on,
you can drive normally.
If the warning continues, and you have not stopped,
pull over, stop, and park the vehicle right away.If there is still no sign of steam, idle the engine for
three minutes while you are parked. If the warning still
exists,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
The overheated engine protection operating mode allows
the vehicle to be driven to a safe place in an emergency
situation. If an overheated engine condition exists, this
protection mode alternates ring groups of cylinders to
help prevent engine damage. In this mode, there will be
a signicant loss in power and engine performance.
The engine coolant temperature gage indicator will move
to the red area, and the engine coolant temperature
warning light will come on, showing that an overheated
engine condition exists. Driving extended miles (km)
and/or towing a trailer in the overheated engine 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 5-13.
5-26

Windshield Washer Fluid
What to Use
When the vehicle needs windshield washer uid, be
sure to read the manufacturer’s instructions before use.
If the vehicle will be operating in an area where the
temperature may fall below freezing, use a uid that has
sufficient protection against freezing.
Adding Washer Fluid
Open the cap with the
washer symbol on it.
Add washer uid until the
reservoir is full.
SeeEngine Compartment Overview on page 5-12
for reservoir location.Notice:
When using concentrated washer uid, follow the
manufacturer’s instructions for adding water.
Do not mix water with ready-to-use washer uid.
Water can cause the solution to freeze and
damage your washer uid tank and other parts of
the washer system. Also, water does not clean as
well as washer uid.
Fill your washer uid tank only three-quarters full
when it is very cold. This allows for expansion if
freezing occurs, which could damage the tank if
it is completely full.
Do not use engine coolant (antifreeze) in your
windshield washer. It can damage your washer
system and paint.
5-35

(h)Change automatic transaxle uid and lter if
the vehicle is mainly driven under one or more of
these conditions:
In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or
delivery service.
(i)Drain, ush and rell cooling system. See Engine
Coolant on page 5-22for what to use. Inspect hoses.
Clean radiator, condenser, pressure cap and ller neck.
Pressure test the cooling system and pressure cap.
(j)Check throttle system for interference or binding
and for damaged or missing parts. Replace parts
as needed. Replace any components that have high
effort or excessive wear. Do not lubricate accelerator or
cruise control cables.
(k)A uid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired
and the uid level checked. Add uid if needed.Owner Checks and Services
These owner checks and services should be performed
at the intervals specied to help ensure the safety,
dependability and emission control performance of your
vehicle. Your GM Goodwrench dealer can assist you
with these checks and services.
Be sure any necessary repairs are completed at once.
Whenever any uids or lubricants are added to your
vehicle, make sure they are the proper ones, as shown
inRecommended Fluids and Lubricants on page 6-13.
At Each Fuel Fill
It is important to perform these underhood checks at
each fuel ll.
Engine Oil Level Check
Check the engine oil level and add the proper oil
if necessary. SeeEngine Oil on page 5-13for
further details.
Notice:It is important to check your oil regularly
and keep it at the proper level. Failure to keep your
engine oil at the proper level can cause damage
to your engine not covered by your warranty.
6-9