2010 CHEVROLET TAHOE service

Voltmeter Gauge
When the engine is not
running, but the ignition is
on, this gauge shows the
battery's state of charge
in DC volts.
When the engine is running, the gauge shows the
condition of the charging system. The charging system
regulates voltage based on the state of the battery for
improved fuel economy and battery life. The gauge may
transition from a higher to lower or a lower to higher
reading, this is normal. Readings between the low and
high warning zones indicate the normal operating
range. The gauge may also read low during the fuel
economy mode, this is normal. Readings in the low warning zone may occur when a
large number of electrical accessories are operating
in the vehicle and the engine is left at an idle for an
extended period. This condition is normal since the
charging system is not able to provide full power at
engine idle. As engine speeds are increased, this
condition should correct itself as higher engine speeds
allow the charging system to create full power. If there
is a problem with the battery charging system, this light
will come on or the SERVICE BATTERY CHARGING
SYSTEM DIC message will display. See
DIC Warnings
and Messages
on page 4‑61and Charging System
Lighton page 4‑34for more information.
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Brake System Warning Light
With the ignition on, the brake system warning light
comes on when the parking brake is set. If the vehicle
is driven with the parking brake engaged, a chime
sounds when the vehicle speed is greater than
8 km/h (5 mph).
The vehicle's hydraulic brake system is divided into
two parts. If one part is not working, the other part can
still work and stop the vehicle. For good braking, both
parts need to be working well.
If the warning light comes on and a chime sounds there
could be a brake problem. Have the brake system
inspected right away.
This light can also come on due to low brake fluid. See
Brakes
on page 6‑42for more information.
United StatesCanada
This light comes on briefly when the ignition key is
turned to ON/RUN. If it does not come on then, have it
fixed so it is ready to warn if there is a problem.
{WARNING:
The brake system might not be working properly if
the brake system warning light is on. Driving with
the brake system warning light on can lead to a
crash. If the light is still on after the vehicle has
been pulled off the road and carefully stopped,
have the vehicle towed for service.
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If the light comes on while driving, pull off the road and
stop carefully. The pedal might be harder to push or
might go closer to the floor. It can take longer to stop.
If the light is still on, have the vehicle towed for service.
SeeTowing Your Vehicle on page 5‑40.
Antilock Brake System (ABS)
Warning Light
For vehicles with the
Antilock Brake System
(ABS), this light comes on
briefly when the engine is
started.
If it does not, have the vehicle serviced by your dealer.
If the system is working normally the indicator light then
goes off.
If the ABS light stays on, turn the ignition off. If the light
comes on while driving, stop as soon as it is safely
possible and turn the ignition off. Then start the engine
again to reset the system. If the ABS light stays on,
or comes on again while driving, the vehicle needs
service. If the regular brake system warning light is not
on, the vehicle still has brakes, but not antilock brakes. If the regular brake system warning light is also on, the
vehicle does not have antilock brakes and there is a
problem with the regular brakes. See
Brake System
Warning Light on page 4‑36.
For vehicles with a Driver Information Center (DIC), see
DIC Warnings and Messages
on page 4‑61for all
brake related DIC messages.
StabiliTrak®Indicator Light
For vehicles with the
StabiliTrak®system, this
light comes on briefly
while starting the engine.
If it does not, have the vehicle serviced by your dealer.
If the system is working normally the indicator light then
goes off.
If the light comes on and stays on while driving, there
could be a problem with the StabiliTrak
®system and the
vehicle might need service. When this warning light is
on, the StabiliTrak
®system is off and does not limit
wheel spin.
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When the Light is On Steady
This indicates that one or more of the tires is
significantly underinflated.
A tire pressure message in the Driver Information
Center (DIC), can accompany the light. SeeDriver
Information Center (DIC)
on page 4‑47for more
information. Stop and check the tires as soon as it is
safe to do so. If underinflated, inflate to the proper
pressure. See Inflation - Tire Pressure
on page 6‑72for more information.
When the Light Flashes First and Then is
On Steady
This indicates that there may be a problem with the
Tire Pressure Monitor System. The light flashes for
about a minute and stays on steady for the remainder
of the ignition cycle. This sequence repeats with every
ignition cycle. See Tire Pressure Monitor Operation
on
page 6‑74for more information.
Malfunction Indicator Lamp
Check Engine Light
A computer system called OBD II (On-Board
Diagnostics-Second Generation) monitors operation
of the fuel, ignition, and emission control systems.
It ensures that emissions are at acceptable levels for
the life of the vehicle, helping to produce a cleaner
environment.
This light should come on
when the ignition is on,
but the engine is not
running, as a check to
show it is working. If it
does not, have the vehicle
serviced by your dealer.
If the check engine light comes on and stays on, while
the engine is running, this indicates that there is an
OBD II problem and service is required.
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Malfunctions often are indicated by the system before
any problem is apparent. Being aware of the light can
prevent more serious damage to the vehicle. This
system assists the service technician in correctly
diagnosing any malfunction.
Notice:If the vehicle is continually driven with this
light on, after a while, the emission controls might
not work as well, the vehicle's fuel economy might
not be as good, and the engine might not run as
smoothly. This could lead to costly repairs that
might not be covered by the vehicle warranty.
Notice: Modifications made to the engine,
transmission, exhaust, intake, or fuel system of
the vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect the vehicle's emission
controls and can cause this light to come on.
Modifications to these systems could lead to costly
repairs not covered by the vehicle warranty. This
could also result in a failure to pass a required
Emission Inspection/Maintenance test. See
Accessories and Modifications on page 6‑4. This light comes on during a malfunction in one of
two ways:
Light Flashing:
A misfire condition has been detected.
A misfire increases vehicle emissions and could
damage the emission control system on the vehicle.
Diagnosis and service might be required.
To prevent more serious damage to the vehicle:
.Reduce vehicle speed.
.Avoid hard accelerations.
.Avoid steep uphill grades.
.If towing a trailer, reduce the amount of cargo
being hauled as soon as it is possible.
If the light continues to flash, when it is safe to do so,
stop the vehicle. Find a safe place to park the vehicle.
Turn the vehicle off, wait at least 10 seconds, and
restart the engine. If the light is still flashing, follow the
previous steps and see your dealer for service as soon
as possible.
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Light On Steady:An emission control system
malfunction has been detected on the vehicle.
Diagnosis and service might be required.
An emission system malfunction might be corrected by
doing the following:
.Make sure the fuel cap is fully installed. See Filling
the Tankon page 6‑11. The diagnostic system
can determine if the fuel cap has been left off or
improperly installed. A loose or missing fuel cap
allows fuel to evaporate into the atmosphere. A few
driving trips with the cap properly installed should
turn the light off.
.If the vehicle has been driven through a deep
puddle of water, the vehicle's electrical system
might be wet. The condition is usually corrected
when the electrical system dries out. A few driving
trips should turn the light off.
.Make sure to fuel the vehicle with quality fuel.
Poor fuel quality causes the engine not to run as
efficiently as designed and can cause: stalling
after start-up, stalling when the vehicle is changed
into gear, misfiring, hesitation on acceleration,
or stumbling on acceleration. These conditions
might go away once the engine is warmed up.
If one or more of these conditions occurs, change
the fuel brand used. It will require at least one full
tank of the proper fuel to turn the light off.
See Gasoline Octane on page 6‑7.
If none of the above have made the light turn off, your
dealer can check the vehicle. The dealer has the
proper test equipment and diagnostic tools to fix any
mechanical or electrical problems that might have
developed.
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Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but readings above the
low pressure zone indicate the normal operating range.
When the oil pressure reaches the low pressure zone,
the OIL PRESSURE LOW STOP ENGINE message
appears in the Driver Information Center (DIC). SeeDIC
Warnings and Messages
on page 4‑61and Engine Oilon page 6‑17for more information.
A reading in the low pressure zone may be caused by
a dangerously low oil level or some other problem
causing low oil pressure. Check the oil as soon as
possible.
{WARNING:
Do not keep driving if the oil pressure is low. The
engine can become so hot that it catches fire.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.
Notice: Lack of proper engine oil maintenance
can damage the engine. The repairs would not be
covered by the vehicle warranty. Always follow the
maintenance schedule in this manual for changing
engine oil.
If the vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
Oil Pressure Light
{WARNING:
Do not keep driving if the oil pressure is low. The
engine can become so hot that it catches fire.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.
Notice: Lack of proper engine oil maintenance can
damage the engine. The repairs would not be
covered by the vehicle warranty. Always follow the
maintenance schedule in this manual for changing
engine oil.
This light comes on briefly while starting the engine.
If it does not, have the vehicle serviced by your dealer.
If the system is working normally the indicator light then
goes off.
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The gauge first indicates empty before the vehicle is out
of fuel, and the vehicle's fuel tank should be filled soon.
When the fuel tank is low, the FUEL LEVEL LOW
message appears in the Driver Information Center
(DIC). SeeDIC Warnings and Messages
on page 4‑61for more information.
Here are some situations owners may experience with
the fuel gauge. None of these indicate a problem with
the fuel gauge.
.At the gas station, the fuel pump shuts off before
the gauge reads full.
.It takes a little more or less fuel to fill up than the
fuel gauge indicated. For example, the gauge may
have indicated the tank was half full, but it actually
took a little more or less than half the tank's
capacity to fill the tank.
.The gauge goes back to empty when the ignition is
turned off.
For vehicles with a Two-mode Hybrid, see the
Two-mode Hybrid manual for more information.
Low Fuel Warning Light
This light, under the fuel
gauge, comes on briefly
while the engine is being
started.
This light and a chime comes on when the fuel tank is
low on fuel. The Driver Information Center also displays
a “FUEL LEVEL LOW” message. SeeDIC Warnings
and Messages
on page 4‑61for more information.
When fuel is added this light and message should go
off. If it does not, have the vehicle serviced by your
dealer.
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