2007 BUICK LUCERNE warning

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 is safe to do
so, pull off the road, shift to PARK (P) or
NEUTRAL (N) and let the engine idle.
2. Turn on your heater to full hot at the highest
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 and you have not
stopped, pull over, stop, and park your vehicle
right away.
If there is still no sign of steam, you can 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.
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 337.
353

How to Add Coolant to the Coolant
Recovery Tank
{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.
If you have not found a problem yet, but the
coolant level is not at the FULL COLD mark, add
a 50/50 mixture ofclean, drinkable waterand
DEX-COOL
®engine coolant at the coolant
recovery tank. SeeEngine Coolant on page 347
for more information.
{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.
When the coolant in the coolant recovery tank is
at the FULL COLD mark, start your vehicle.
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If the overheat warning continues, there is one
more thing you can try. You can add the proper
coolant mixture directly to the radiator, but be sure
the cooling system is cool before you do it.
{CAUTION:
Steam and scalding liquids from a hot
cooling system can blow out and burn
you badly. They are under pressure, and if
you turn the radiator pressure cap — even
a little — they can come out at high
speed. Never turn the cap when the
cooling system, including the radiator
pressure cap, is hot. Wait for the cooling
system and radiator pressure cap to cool
if you ever have to turn the pressure cap.
How to Add Coolant to the Radiator
1. You can remove the radiator pressure cap
when the cooling system, including the
radiator pressure cap and upper radiator hose,
is no longer hot. Turn the pressure cap
slowly counterclockwise.
If you hear a hiss, wait for that to stop. A hiss
means there is still some pressure left.
2. Then keep turning the pressure cap. Remove
the pressure cap.
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If no coolant is visible in the surge tank, add
coolant as follows:
{CAUTION:
Steam and scalding liquids from a hot
cooling system can blow out and burn
you badly. They are under pressure, and if
you turn the coolant surge tank pressure
cap — even a little — they can come out at
high speed. Never turn the cap when the
cooling system, including the coolant
surge tank pressure cap, is hot. Wait for
the cooling system and coolant surge
tank pressure cap to cool if you ever have
to turn the pressure cap.
{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.
362

Brakes
Brake Fluid
Your brake master
cylinder reservoir is
lled with DOT-3 brake
uid. SeeEngine
Compartment Overview
on page 334for the
location of the reservoir.
There are only two reasons why the brake uid
level in the reservoir might go down. The rst
is that the brake uid goes down to an acceptable
level during normal brake lining wear. When
new linings are put in, the uid level goes back
up. The other reason is that uid is leaking out of
the brake system. If it is, you should have your
brake system xed, since a leak means that
sooner or later your brakes will not work well, or
will not work at all.So, it is not a good idea to top off your brake uid.
Adding brake uid will not correct a leak. If you
add uid when your linings are worn, then you will
have too much uid when you get new brake
linings. You should add or remove brake uid, as
necessary, only when work is done on the
brake hydraulic system.
{CAUTION:
If your vehicle has too much brake uid, it
can spill on the engine. The uid will burn
if the engine is hot enough. You or others
could be burned, and your vehicle could
be damaged. Add brake uid only when
work is done on the brake hydraulic
system.
When your brake uid falls to a low level, your
brake warning light will come on. SeeBrake
System Warning Light on page 201.
367

Brake Wear
Your vehicle has four-wheel disc brakes.
Disc brake pads have built-in wear indicators that
make a high-pitched warning sound when the
brake pads are worn and new pads are needed.
The sound may come and go or be heard all
the time your vehicle is moving, except when you
are pushing on the brake pedal rmly.
{CAUTION:
The brake wear warning sound means that
soon the brakes will not work well. That
could lead to an accident. When you hear
the brake wear warning sound, have your
vehicle serviced.Notice:Continuing to drive with worn-out
brake pads could result in costly brake repair.
Some driving conditions or climates may cause
a brake squeal when the brakes are rst applied or
lightly applied. This does not mean something is
wrong with your brakes.
Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated,
inspect brake pads for wear and evenly tighten
wheel nuts in the proper sequence to GM torque
specications.
Brake linings should always be replaced as
complete axle sets.
Brake Pedal Travel
See your dealer if the brake pedal does not return
to normal height, or if there is a rapid increase in
pedal travel. This could be a sign of brake trouble.
Brake Adjustment
Every time you apply the brakes, with or without
the vehicle moving, your brakes adjust for wear.
369

Replacing Brake System Parts
The braking system on a vehicle is complex. Its
many parts have to be of top quality and work well
together if the vehicle is to have really good
braking. Your vehicle was designed and tested
with top-quality GM brake parts. When you replace
parts of your braking system — for example,
when your brake linings wear down and you need
new ones put in — be sure you get new
approved GM replacement parts. If you do not,
your brakes may no longer work properly.
For example, if someone puts in brake linings that
are wrong for your vehicle, the balance between
your front and rear brakes can change — for
the worse. The braking performance you have
come to expect can change in many other ways
if someone puts in the wrong replacement
brake parts.
Battery
Your vehicle has a maintenance free battery.
When it is time for a new battery, get one that has
the replacement number shown on the original
battery’s label. We recommend an ACDelco
®
replacement battery.
Warning:Battery posts, terminals, and related
accessories contain lead and lead compounds,
chemicals known to the State of California
to cause cancer and reproductive harm. Wash
hands after handling.
The battery is located under the rear seat cushion.
To access the battery, see “Removing the Rear
Seat Cushion” underRear Underseat Fuse
Block on page 431. You do not need to access
the battery to jump start your vehicle. See
Jump Starting on page 372.
370

The TPMS is designed to alert the driver, if a low
tire pressure condition exists. If your vehicle
has the Driver Information Center (DIC), the driver
may also check tire pressure levels using the
DIC buttons located on the instrument panel.
When a low tire pressure condition is detected,
the TPMS will illuminate the low tire pressure
warning symbol, located on the instrument panel
cluster, and at the same time a message to check
the pressure in a specic tire will also appear on
the DIC display. The low tire pressure warning
symbol on the instrument panel cluster and
the CHECK TIRE PRESSURE warning message
on the DIC display will appear at each ignition
cycle until the tires are inated to the correct
ination pressure. For additional information and
details about the DIC operation and displays
seeDIC Controls and Displays on page 212and
DIC Warnings and Messages on page 221.
You may notice, during cooler weather conditions,
that the tire pressure monitor light, located on
the instrument panel cluster, and the CHECK TIRE
PRESSURE message will appear when the
vehicle is rst started and the turn off as you startto drive the vehicle. This could be an early
indicator that the tire pressures are getting low
and need to be inated to the proper pressure.
Each tire, including the spare (if provided), should
be checked monthly when cold and inated to
the ination pressure recommended by the vehicle
manufacturer on the vehicle placard or tire
ination pressure label. (If your vehicle has tires of
a different size than the size indicated on the
vehicle placard or tire ination pressure label, you
should determine the proper tire ination
pressure for those tires.)
As an added safety
feature, your vehicle
has been equipped with
a tire pressure
monitoring system
(TPMS) that illuminates
a low tire pressure
telltale when one
or more of your tires is
signicantly
under-inated.
394