ignition CHEVROLET TAHOE 2005 2.G Service Manual

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 maximum power.
You can only drive for a short time with the reading
in either warning zone. If you must drive, turn off
all unnecessary accessories.
Readings in either warning zone indicate a possible
problem in the electrical system. Have the vehicle
serviced as soon as possible.Brake System Warning Light
With the ignition on, the brake system warning light will
ash when you set the parking brake. The light will
ash if the parking brake doesn’t release fully. If you try
to drive with the parking brake engaged, a chime will
sound when the vehicle speed is greater than 3 mph
(5 km/h).
Your vehicle’s hydraulic brake system is divided into two
parts. If one part isn’t working, the other part can still
work and stop you. For good braking, though, you need
both parts working well.
If the warning light comes on and a chime sounds there
could be a brake problem. Have your brake system
inspected right away.
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This light should come on briey when you turn the
ignition key to RUN. If it doesn’t come on then, have it
xed so it will be ready to warn you if there’s a problem.
If the light comes on while you are driving, pull off the
road and stop carefully. You may notice that the pedal is
harder to push or may go closer to the oor. It may
take longer to stop. If the light is still on, have the vehicle
towed for service. SeeTowing Your Vehicle on
page 4-62.
{CAUTION:
Your brake system may not be working properly
if the brake system warning light is on. Driving
with the brake system warning light on can lead
to an accident. If the light is still on after you
have pulled off the road and stopped carefully,
have the vehicle towed for service. United States
Canada
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Anti-Lock Brake System Warning
Light
With the anti-lock brake
system, this light will come
on when you start your
engine and may stay on for
several seconds.
That’s normal. If the light doesn’t come on then, have it
xed so it will be ready to warn you if there is a problem.
If the light stays on, or comes on when you’re driving,
your vehicle needs service. You will also hear a
chime sound when the light is on steady. If the regular
brake system warning light isn’t on, you still have
brakes, but you don’t have anti-lock brakes. If the
regular brake system warning light is also on you don’t
have anti-lock brakes and there’s a problem with
your regular brakes. In addition to both lights, you will
also hear a chime sound on the rst occurrence of
a problem and each time the vehicle is shut off and then
restarted. SeeBrake System Warning Light on
page 3-43.
Traction Off Light
If you have the Traction
Assist System, this light
should come on briey
when you turn the ignition
to RUN.
If the light does not come on then, the system may
require service; have it xed so it will be there to warn
you if the system is turned off.
If the light stays on, or comes on when you are driving,
there may be a problem with your Traction Assist
System and your vehicle may need service. When this
light is on, the system will not limit wheel spin. Adjust
your driving accordingly.
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Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
It also provides an indicator of how hard your vehicle is
working. During a majority of the operation, the gage
will read 210°F (100°C) or less. If you are pulling a load
or going up hills, it is normal for the temperature to
uctuate and approach the 250°F (122°C) mark. If the
gage reaches the 260°F (125°C) mark, it indicates
that the cooling system is working beyond its capacity.
SeeEngine Overheating on page 5-28.
Transmission Temperature Gage
Your vehicle may be equipped with a transmission
temperature gage.
When your ignition is on, the gage shows the
temperature of the transmission uid. The normal
operating range is from 180°F to 200°F (82°C to 93°C).
At approximately 265°F (130°C), the message center
will display a TRANSMISSION HOT message and
the transmission will enter a transmission protection
mode. When the transmission enters the protection
mode, you may notice a change in the transmission
shifting patterns. The transmission will return to normal
shifting patterns when the transmission uid temperature
falls below 260°F (127°C). United States
CanadaUnited StatesCanada
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Tire Pressure Light
If your vehicle is equipped
with the Tire Pressure
Monitor system, this light
will come on if the
system detects low tire
pressure.
A CHECK TIRE PRESSURE DIC message will
accompany the light.
This light will also come on for a bulb check when the
vehicle is started.
SeeTire Pressure Monitor System on page 5-67for
more information.
For more information on your tires, seeTires on
page 5-60.
Malfunction Indicator Lamp
Check Engine Light
Your vehicle is equipped
with a computer which
monitors operation of the
fuel, ignition, and emission
control systems.
This system is called OBD II (On-Board
Diagnostics-Second Generation) and is intended to
assure that emissions are at acceptable levels for the
life of the vehicle, helping to produce a cleaner
environment. The check engine light comes on to
indicate that there is a problem and service is required.
Malfunctions often will be indicated by the system
before any problem is apparent. This may prevent more
serious damage to your vehicle. This system is also
designed to assist your service technician in correctly
diagnosing any malfunction.
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Notice:If you keep driving your vehicle with this
light on, after awhile, your emission controls
may not work as well, your fuel economy may not
be as good, and your engine may not run as
smoothly. This could lead to costly repairs that may
not be covered by your warranty.
Notice:Modications made to the engine,
transmission, exhaust, intake, or fuel system of
your vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect your vehicle’s emission
controls and may cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by your warranty. This may
also result in a failure to pass a required Emission
Inspection/Maintenance test.This light should come on, as a check to show you it is
working, when the ignition is on and the engine is
not running. If the light does not come on, have it
repaired. This light will also come on during a
malfunction in one of two ways:
Light Flashing— A misre condition has been
detected. A misre increases vehicle emissions and
may damage the emission control system on your
vehicle. Diagnosis and service may be required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service may be required.
3-49

Tow/Haul Mode Light
This light is displayed
when the Tow/Haul mode
has been activated.
For more information, seeTowing a Trailer on
page 4-67.
Fuel Gage
The fuel gage, when the ignition is on, tells you about
how much fuel you have left in your tank.
The gage will rst indicate empty before you are out of
fuel, and you should get more fuel as soon as
possible.
When the fuel tank is low, the FUEL LEVEL LOW
message will appear. SeeDriver Information
Center (DIC) on page 3-56.
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3-54

Here are some situations you may experience with your
fuel gage. None of these indicate a problem with the
fuel gage.
At the gas station, the fuel pump shuts off before
the gage reads full.
It takes a little more or less fuel to ll up than the
fuel gage indicated. For example, the gage may
have indicated the tank was half full, but it actually
took a little more or less than half the tank’s
capacity to ll the tank.
The gage goes back to empty when you turn off the
ignition.
Low Fuel Warning Light
The light next to the fuel gage will come on briey when
you are starting the engine.
This light comes on when the fuel tank is low on fuel.
To turn it off, add fuel to the fuel tank. SeeFuel on
page 5-5.
3-55

DIC Operation and Displays
The Driver Information Center (DIC) comes on when the
ignition is on. After a short delay, the DIC will display
the information that was last displayed before the engine
was turned off.
The DIC has different modes which can be accessed by
pressing the four DIC buttons located on the steering
wheel. These buttons are trip information, fuel
information, customization and select. The button
functions are detailed in the following pages.
Trip Information Button
3
(Trip Information):Press the trip information
button to scroll through the ODOMETER, TRIP A,
TRIP B, TIRE PRESSURES, TIMER and
ENGINE HOURS.
Odometer:Press the trip information button until
ODOMETER appears on the display. This mode shows
the total distance the vehicle has been driven in
either miles or kilometers. Pressing the reset stem
located on the instrument cluster with the vehicle off will
also display the odometer.Trip A:Press the trip information button until TRIP A
appears on the display. This mode shows the current
distance traveled since the last reset for TRIP A in either
miles or kilometers.
Trip B:Press the trip information button until TRIP B
appears on the display. This mode shows the current
distance traveled since the last reset for TRIP B in either
miles or kilometers.
To reset TRIP A or TRIP B information, press and hold
the select button for one second while in one of the
trip modes. This will reset the information for TRIP A
or TRIP B.
You can also reset TRIP A or TRIP B while they are
displayed by pressing the reset stem on the cluster.
If you press and hold the reset stem or the select button
for four seconds, the display will show the distance
traveled since the last ignition cycle for TRIP A or
TRIP B.
SeeTrip Odometer on page 3-38for more information.
3-57

Tire Pressures:The tire pressure mode is available
only on vehicles equipped with a tire pressure monitor.
Press the trip information button until TIRE
PRESSURES appears on the display. This mode shows
the tire pressure in pounds per square inch (psi) or
kilopascals (kPa). Press the select button to scroll
through the following information:
LF TIRE shows the tire pressure for the left
front tire.
RF TIRE shows the tire pressure for the right
front tire.
LR TIRE shows the tire pressure for the left
rear tire.
RR TIRE shows the tire pressure for the right
rear tire.
Timer:The DIC can be used as a timer. Press the
select button while TIMER is displayed to start the timer.
The display will show the amount of time that has
passed since the timer was last reset, not including time
the ignition is off. Time will continue to be counted as
long as the ignition is on, even if another display is being
shown on the DIC. The timer will record up to 99 hours,
59 minutes and 59 seconds (99:59:59) after which
the display will roll back to zero.To stop the counting of time, press the select button
briey while TIMER is displayed.
To reset the timer to zero, press and hold the select
button while TIMER is displayed.
Engine Hours:Press the trip information button until
ENGINE HOURS appears on the display. This
mode shows the total number of hours the engine has
run. Pressing and holding the reset stem located on
the instrument cluster for about four seconds will also
display the engine hour information after the odometer is
displayed when the vehicle is off.
Fuel Information Button
t
(Fuel Information):Press the fuel information
button to scroll through the range, fuel used, average
fuel economy and the engine oil life system.
Fuel Range:Press the fuel information button until
RANGE appears on the display. This mode shows the
remaining distance you can drive without refueling.
It is based on fuel economy and the fuel remaining in
the tank. The display will show LOW if the fuel level
is low.
The fuel economy data used to determine fuel range is
an average of recent driving conditions. As your
driving conditions change, this data is gradually updated.
Fuel range cannot be reset.
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