AC system GMC SIERRA 2001 Workshop Manual

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The Instrument Panel - Your Information System

2-81
The main components of your instrument panel are the following:
A. Dome Lamp Switch
B. Lamp Controls
C. Air Outlets
D. Automatic Transfer Case (If Equipped)/Electronic
Transfer Case (If Equipped)/Traction Assist
System (If Equipped)
E. Multifunction Lever
F. Instrument Cluster
G. Gearshift Lever (Automatic Transmission)
H. Tow/Haul Selector Switch
I. Audio System
J. Comfort Control SystemK. Glove Box
L. Passenger Air Bag Off Switch
M. Manual Selectable Ride Control (If Equipped)
N. Ashtray
O. Storage Area or Compact Disc Player (If Equipped)
P. Rear Window Defogger Switch (If Equipped)
Q. Lighter and Accessory Power Outlets
R. Parking Brake Release
S. Tilt Lever (If Equipped)
T. Center Instrument Panel Utility Block
U. Hood Release
V. Instrument Panel Fuse Block

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Warning Lights, Gages
and Indicators
This part describes the warning lights and gages that
may be on your vehicle. The pictures will help you
locate them.
Warning lights and gages can signal that something is
wrong before it becomes serious enough to cause an
expensive repair or replacement. Paying attention to
your warning lights and gages could also save you or
others from injury.
Warning lights come on when there may be or is a
problem with one of your vehicle's functions. As you
will see in the details on the next few pages, some
warning lights come on briefly when you start the
engine just to let you know they're working. If you are
familiar with this section, you should not be alarmed
when this happens.
Gages can indicate when there may be or is a problem
with one of your vehicle's functions. Often gages and
warning lights work together to let you know when
there's a problem with your vehicle.When one of the warning lights comes on and stays on
when you are driving, or when one of the gages shows
there may be a problem, check the section that tells you
what to do about it. Please follow this manual's advice.
Waiting to do repairs can be costly
-- and even
dangerous. So please get to know your warning lights
and gages. They're a big help.
Your vehicle may also have a driver information system
that works along with the warning lights and gages.
See ªMessage Centerº in the Index.
Safety Belt Reminder Light
When the key is turned to RUN or START, a chime will
come on for about six seconds to remind people to
fasten their safety belts, unless the driver's safety belt is
already buckled.
The safety belt light will
also come on and stay on
for about 20 seconds, then
it will flash for
about 55 seconds.
If the driver's belt is already buckled, neither the chime
nor the light will come on.

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Air Bag Readiness Light
There is an air bag readiness light on the instrument
panel, which shows the air bag symbol. The system
checks the air bag's electrical system for malfunctions.
The light tells you if there is an electrical problem. The
system check includes the air bag sensors, the air bag
modules, the wiring, the passenger air bag suppression
circuit and the crash sensing and diagnostic module. For
more information on the air bag system, see ªAir Bagº
in the Index.
This light will come on
when you start your vehicle,
and it will flash for a few
seconds. Then the light
should go out. This means
the system is ready.
If the air bag readiness light stays on after you start the
vehicle or comes on when you are driving, your air bag
system may not work properly. Have your vehicle
serviced right away.
CAUTION:
If the air bag readiness light stays on after you
start your vehicle, it means the air bag system
may not be working properly. The air bags in
your vehicle may not inflate in a crash, or they
could even inflate without a crash. To help avoid
injury to yourself or others, have your vehicle
serviced right away if the air bag readiness light
stays on after you start your vehicle.
The air bag readiness light should flash for a few seconds
when you turn the ignition key to RUN. If the light
doesn't come on then, have it fixed so it will be ready to
warn you if there is a problem.

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CAUTION:
If the air bag readiness light ever comes on when
you have turned off the air bag, it means that
something may be wrong with the air bag system.
The right front passenger's air bag could inflate
even though the switch is off.
If your vehicle is a regular cab pickup and this
ever happens, don't let anyone whom the
national government has identified as a member
of a passenger air bag risk group sit in the right
front passenger's position (for example, don't
secure a rear
-facing child restraint in your
vehicle) until you have your vehicle serviced.
If your vehicle is an extended cab pickup and this
ever happens, don't let anyone whom the
national government has identified as a member
of a passenger air bag risk group sit in the right
front passenger's position (for example, don't
secure a rear
-facing child restraint in the right
front passenger's seat) until you have your
vehicle serviced.
Voltmeter
United States Canada
When your engine is not running, but the ignition is in
RUN, this gage shows your battery's state of charge
in DC volts.
When the engine is running, the gage shows the
condition of the charging system. Readings between the
low and high warning zones indicate the normal
operating range.

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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.
Shift Light (If Equipped)
This light is used on
some models with
manual transmissions.
The SHIFT indicator light will help you get the best fuel
economy. See ªShift Lightº or ªShift Speedsº in the
index for more information.
Brake System Warning Light
With the ignition on, the brake system warning light will
flash when you set the parking brake. The light will flash
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, there could be a brake
problem. Have your brake system inspected right away.
United States Canada

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This light should come on briefly when you turn the
ignition key to RUN. If it doesn't come on then, have it
fixed 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, the pedal may go closer to the floor.
It may take longer to stop. If the light is still on, have the
vehicle towed for service. See ªTowing Your Vehicleº in
the Index.
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've
pulled off the road and stopped carefully, have
the vehicle towed for service.
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 stays on, or comes on when you're driving,
your vehicle needs service. 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. See
ªBrake System Warning Lightº earlier in this section.
The anti
-lock brake system warning light should come
on briefly when you turn the ignition key to RUN. If the
light doesn't come on then, have it fixed so it will be
ready to warn you if there is a problem.

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Engine Coolant Temperature Gage
United States Canada
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
fluctuate 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.
See ªEngine Overheatingº in the Index.
Transmission Temperature Gage
(If Equipped)
United States Canada
Your vehicle may be equipped with a transmission
temperature gage.
When your ignition is on, the gage shows the temperature
of the transmission fluid. The normal operating range is
from 100
F (38
C) to about 265
F (130
C).

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Low Traction Light (If Equipped)
If you have the Traction
Assist System, this light
will come on when the
system is limiting wheel
spin. See ªTraction Assist
Systemº in the Index.
You may feel or hear the system working or notice a
lack of accelerator response, but this is normal.
The LOW TRACTION light also comes on briefly when
you turn your ignition to RUN. If the light doesn't come
on then, the system may require service; have it fixed so
it will be there to tell you when the Traction Assist
System is active. Slippery road conditions may exist if
the LOW TRACTION light comes on, so adjust your
driving accordingly.
Traction Off Light (If Equipped)
If you have the Traction
Assist System, this light
should come on briefly
when you turn the ignition
to RUN.
If the light doesn't come on then, the system may
require service; have it fixed so it will be there to warn
you if the system is turned off.
If the TRACTION OFF light stays on, or comes on
when you're 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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The TRACTION OFF light may come on for the
following reasons:

If you turn the system off by pressing the TAS on/off
button the light will come on and stay on. To turn the
system back on, press the button again; the light
should go off.

If you move the shift lever to FIRST (1), the light
will come on and stay on to indicate that the Traction
Assist System is off. This is normal operation. To
turn the system back on, move the shift lever back to
a position other than FIRST (1); the light should go
off. See ªTraction Assist Systemº in the Index.

The light will come on and stay on if the TAS automatic
engagement feature has been turned off. To turn the
system on, press the TAS off/on button; the light should
go off. To turn the automatic engagement feature back
on, see ªTraction Assist Systemº in the Index.

If the Traction Assist System is affected by an
anti
-lock brake system, Traction Assist System or
engine
-related problem, the system will turn off and
the light will come on. Have your vehicle serviced.

If the vehicle is driven over an extremely rough road,
the system will turn off and the light will come on.
The light will go off a few seconds after the rough
road conditions go away or when the vehicle comes
to a complete stop. This is normal operation.
Malfunction Indicator Lamp (Service
Engine Soon Light in the United States or
Check Engine Light in Canada)
United States Canada
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
SERVICE ENGINE SOON or 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.