2009 CHEVROLET TAHOE warning

If No Steam Is Coming From The
Engine Compartment
The ENGINE OVERHEATED STOP ENGINE or the
ENGINE OVERHEATED IDLE ENGINE message, along
with a low coolant condition, can indicate a serious
problem.
If you get an engine overheat warning, but see or
hear no steam, the problem may not be too serious.
Sometimes the engine can get a little too hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer. SeeTowing a Trailer on page 4-50.
If you get the ENGINE OVERHEATED STOP ENGINE or
the ENGINE OVERHEATED IDLE ENGINE message
with no sign of steam, try this for a minute or so:
If the overheat warning is displayed with no sign of
steam:
1. Turn the air off.
2. Turn the heater on to the highest temperature and
to the highest fan speed. Open the windows as
necessary.
3. In heavy traffic, let the engine idle in N (Neutral)
while stopped. If it is safe to do so, pull off the
road, shift to P (Park) or N (Neutral) and let
the engine idle.If the temperature overheat gage is no longer in the
overheat zone or an overheat warning no longer displays,
the vehicle can be driven. Continue to drive the vehicle
slow for about 10 minutes. Keep a safe vehicle distance
from the car in front of you. If the warning does not come
back on, continue to drive normally.
If the warning continues, pull over, stop, and park the
vehicle right away.
If there is no sign of steam, idle the engine for
three minutes while parked. If the warning is still
displayed, turn off the engine until it cools down.
Also, see “Overheated Engine Protection Operating
Mode” later in this section.Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
ENGINE POWER IS REDUCED message 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 the 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.
5-36

Brakes
Brake Fluid
The brake master cylinder
reservoir is lled with
DOT-3 brake uid. See
Engine Compartment
Overview on page 5-14for
the location of the reservoir.
There are only two reasons why the brake uid level in
the reservoir might go down:
The brake uid level goes down because of normal
brake lining wear. When new linings are installed,
the uid level goes back up.
A uid leak in the brake hydraulic system can also
cause a low uid level. Have the brake hydraulic
system xed, since a leak means that sooner
or later the brakes will not work well.Do not top off the brake uid. Adding uid does not
correct a leak. If uid is added when the linings
are worn, there will be too much uid when new brake
linings are installed. Add or remove brake uid, as
necessary, only when work is done on the brake
hydraulic system.
{CAUTION:
If too much brake uid is added, it can spill on the
engine and burn, if the engine is hot enough. You
or others could be burned, and the vehicle could
be damaged. Add brake uid only when work is
done on the brake hydraulic system. See
“Checking Brake Fluid” in this section.
When the brake uid falls to a low level, the brake
warning light comes on. SeeBrake System Warning
Light on page 3-40.
Refer to the Maintenance Schedule to determine when
to check the brake uid. SeeScheduled Maintenance
on page 6-4.
5-40

Brake Wear
This vehicle has 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 can come and go or be heard all
the time the vehicle is moving, except when applying
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 the brake wear warning sound is
heard, have the vehicle serviced.
Notice:Continuing to drive with worn-out brake
pads could result in costly brake repair.Some driving conditions or climates can cause a brake
squeal when the brakes are rst applied or lightly applied.
This does not mean something is wrong with the 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 torque specications in
Capacities and Specifications on page 5-121.
Brake linings should always be replaced as complete
axle sets.Brake Pedal Travel
See your dealer/retailer 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 that brake service
might be required.
5-42

Brake Adjustment
Every brake stop, the disc brakes adjust for wear.
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. The vehicle
was designed and tested with top-quality brake parts.
When parts of the braking system are replaced — for
example, when the brake linings wear down and new
ones are installed — be sure to get new approved
replacement parts. If this is not done, the brakes might
not work properly. For example, if someone puts in brake
linings that are wrong for the vehicle, the balance
between the front and rear brakes can change — for the
worse. The braking performance expected can change in
many other ways if the wrong replacement brake parts
are installed.
Battery
If the vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
This vehicle has a maintenance free battery. When it is
time for a new battery, see your dealer/retailer for
one that has the replacement number shown on the
original battery’s label. SeeEngine Compartment
Overview on page 5-14for battery location.
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.
5-43

Tire Pressure Monitor Operation
If your vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
This vehicle may have a Tire Pressure Monitor System
(TPMS). The TPMS is designed to warn the driver when
a low tire pressure condition exists. TPMS sensors are
mounted onto each tire and wheel assembly, excluding
the spare tire and wheel assembly. The TPMS sensors
monitor the air pressure in the vehicle’s tires and transmit
the tire pressure readings to a receiver located in the
vehicle.
When a low tire pressure
condition is detected, the
TPMS illuminates the low
tire pressure warning light
located on the instrument
panel cluster.
At the same time a message to check the pressure in a
specic tire appears on the Driver Information Center
(DIC) display. The low tire pressure warning light and the
DIC warning message come on at each ignition cycle
until the tires are inated to the correct ination pressure.Using the DIC, tire pressure levels can be viewed by the
driver. For additional information and details about the
DIC operation and displays seeDIC Operation and
Displays (With DIC Buttons) on page 3-52orDIC
Operation and Displays (Without DIC Buttons) on
page 3-58andDIC Warnings and Messages on
page 3-64.
The low tire pressure warning light may come on in cool
weather when the vehicle is rst started, and then
turn off as you start to drive. This could be an early
indicator that the air pressure in the tire(s) are getting
low and need to be inated to the proper pressure.
A Tire and Loading Information label, attached to your
vehicle, shows the size of your vehicle’s original
equipment tires and the correct ination pressure for
your vehicle’s tires when they are cold. SeeLoading the
Vehicle on page 4-33, for an example of the Tire and
Loading Information label and its location on your
vehicle. Also seeInflation - Tire Pressure on page 5-70.
Your vehicle’s TPMS can warn you about a low tire
pressure condition but it does not replace normal tire
maintenance. SeeTire Inspection and Rotation on
page 5-76andTires on page 5-62.
Notice:Liquid tire sealants could damage the Tire
Pressure Monitor System (TPMS) sensors. Sensor
damage caused by using a tire sealant is not covered
by your warranty. Do not use liquid tire sealants.
5-73

TPMS Malfunction Light and Message
The TPMS will not function properly if one or more of the
TPMS sensors are missing or inoperable. When the
system detects a malfunction, the low tire warning light
ashes for about one minute and then stays on for the
remainder of the ignition cycle. A DIC warning message
is also displayed. The low tire warning light and DIC
warning message come on at each ignition cycle until the
problem is corrected. Some of the conditions that can
cause the malfunction light and DIC message to come
on are:
One of the road tires has been replaced with the
spare tire. The spare tire does not have a TPMS
sensor. The TPMS malfunction light and DIC
message should go off once you re-install the road
tire containing the TPMS sensor.
The TPMS sensor matching process was started but
not completed or not completed successfully after
rotating the vehicle’s tires. The DIC message and
TPMS malfunction light should go off once the TPMS
sensor matching process is performed successfully.
See “TPMS Sensor Matching Process” later in this
section.
One or more TPMS sensors are missing or
damaged. The DIC message and the TPMS
malfunction light should go off when the TPMS
sensors are installed and the sensor matching
process is performed successfully. See your dealer/
retailer for service.
Replacement tires or wheels do not match your
vehicle’s original equipment tires or wheels. Tires
and wheels other than those recommended for your
vehicle could prevent the TPMS from functioning
properly. SeeBuying New Tires on page 5-78.
Operating electronic devices or being near facilities
using radio wave frequencies similar to the TPMS
could cause the TPMS sensors to malfunction.
If the TPMS is not functioning it cannot detect or signal a
low tire condition. See your dealer/retailer for service if
the TPMS malfunction light and DIC message comes on
and stays on.
5-74

{CAUTION:
Mixing tires could cause you to lose control while
driving. If you mix tires of different sizes, brands,
or types (radial and bias-belted tires), the vehicle
might not handle properly, and you could have a
crash. Using tires of different sizes, brands, or
types could also cause damage to your vehicle.
Be sure to use the same size, brand, and type
tires on all wheels.
Your vehicle may have a different size spare than
the road tires (those originally installed on your
vehicle). When new, your vehicle included a spare
tire and wheel assembly with a similar overall
diameter as your vehicle’s road tires and wheels,
so it is all right to drive on it. Because this spare
was developed for use on your vehicle, it will not
affect vehicle handling.
{CAUTION:
If you use bias-ply tires on the vehicle, the
wheel rim anges could develop cracks after
many miles of driving. A tire and/or wheel
could fail suddenly, causing a crash. Use
only radial-ply tires with the wheels on the
vehicle.
If you must replace your vehicle’s tires with those that
do not have a TPC Spec number, make sure they
are the same size, load range, speed rating, and
construction type (radial and bias-belted tires) as your
vehicle’s original tires.
Vehicles that have a tire pressure monitoring system
may give an inaccurate low-pressure warning if non-TPC
spec rated tires are installed on your vehicle. Non-TPC
Spec rated tires may give a low-pressure warning
that is higher or lower than the proper warning level you
would get with TPC Spec rated tires. SeeTire
Pressure Monitor System on page 5-71.
Your vehicle’s original equipment tires are listed on the
Tire and Loading Information Label. SeeLoading the
Vehicle on page 4-33, for more information about the Tire
and Loading Information Label and its location on your
vehicle.
5-79

Treadwear
The treadwear grade is a comparative rating based
on the wear rate of the tire when tested under
controlled conditions on a specied government
test course. For example, a tire graded 150 would
wear one and a half (1.5) times as well on the
government course as a tire graded 100. The
relative performance of tires depends upon the
actual conditions of their use, however, and may
depart signicantly from the norm due to variations
in driving habits, service practices, and differences
in road characteristics and climate.
Traction – AA, A, B, C
The traction grades, from highest to lowest, are
AA, A, B, and C. Those grades represent the tire’s
ability to stop on wet pavement as measured under
controlled conditions on specied government test
surfaces of asphalt and concrete. A tire marked C
may have poor traction performance.
{WARNING:
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration,
cornering, hydroplaning, or peak traction
characteristics.
5-81