tow GMC SIERRA CLASSIC 2007 Workshop Manual

This light should come on briey when you turn
the ignition key to RUN. If it does not come
on then, have it xed so it will be ready to warn
you if there is 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 423.
{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.
Anti-Lock Brake System Warning
Light
With the Anti-Lock Brake
System (ABS), this light
will come on when you
start your engine and
may stay on for several
seconds.
That is normal. If the light does not 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 are
driving, your vehicle needs service. A chime
will sound when the light stays on. If the regular
brake system warning light is not on, you still have
brakes, but you do not have ABS. If the regular
brake system warning light is also on you do
not have ABS and there is 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 254.
255

If the transmission continues to operate above
265°F (130°C), contact your nearest dealer or the
GM Roadside Assistance Center. SeeRoadside
Assistance Program on page 644.
Notice:If you drive your vehicle with the
transmission temperature gage above normal
operating range, you can damage the
transmission. This could lead to costly repairs
that would not be covered by your warranty.
Do not drive your vehicle while the
transmission temperature gage reading is
above normal. See your dealer for service.
The following situations can cause the
transmission to operate at higher temperatures:
Towing a trailer
Hot outside air temperatures
Hauling a large or heavy load
Low transmission uid level
High transmission uid level
Restricted air ow to the radiator and the
auxiliary transmission oil cooler, if equipped.A temporary solution to reduce hotter transmission
operating temperatures may be to let the
transmission cool down. If the transmission is
operated at higher temperatures on a frequent
basis, seeScheduled Maintenance (Gasoline
Engine) on page 617for the proper transmission
maintenance intervals.
Malfunction Indicator Lamp
Check Engine Light
Your vehicle has a
computer which
monitors operation of
the fuel, ignition,
and emission control
systems.
258

If the Light is Flashing
The following may prevent more serious damage
to your vehicle:
Reducing vehicle speed
Avoiding hard accelerations
Avoiding steep uphill grades
If you are towing a trailer, reduce the amount
of cargo being hauled as soon as it is
possible
If the light stops ashing and remains on steady,
see “If the Light Is On Steady” following.
If the light continues to ash, when it is safe to do
so, stop the vehicle. Find a safe place to park
your vehicle. Turn the key off, wait at least
10 seconds and restart the engine. If the light
remains on steady, see “If the Light Is On Steady”
following. If the light is still ashing, follow the
previous steps, and see your dealer for service as
soon as possible.
If the Light Is On Steady
You may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully
install the cap. SeeFilling the Tank on page 474.
The diagnostic system can determine if the
fuel cap has been left off or improperly installed.
A loose or missing fuel cap will allow fuel to
evaporate into the atmosphere. A few driving trips
with the cap properly installed should turn the
light off.
Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The
condition will usually be corrected when the
electrical system dries out. A few driving trips
should turn the light off.
260

Tow/Haul Mode Light
This light comes on
when the Tow/Haul
mode has been
activated.
For more information, seeTow/Haul Mode on
page 147.
Cargo Lamp Light
This light comes on
when the cargo lamp is
in use. For more
information seeCargo
Lamp on page 228.
Fuel Gage
When the ignition is on, the fuel gage 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. SeeDIC Warnings and
Messages on page 270for more information.
United StatesCanada
264

SERVICE BRAKE BOOSTER
{CAUTION:
Your brake system may not be working
properly if the SERVICE BRAKE
BOOSTER message is displayed.
If the brake system warning light is also
on, you should have the vehicle towed for
service. SeeBrake System Warning Light
on page 254.
If the brake system warning light is not
on, you still have brakes, but the
supplemental brake assist system on
vehicles with rear disc brakes may not
operate properly. In the event of a vacuum
loss, you may not have vacuum power
assist for braking. The brake pedal will be
harder to push and it will take longer to
stop. If you continue to drive with this
message displayed it can lead to a crash.
Have the brake system serviced as soon
as possible.If your vehicle has vacuum assist power brakes,
this message will be displayed on the DIC
when there is a problem with the Supplemental
Brake Assist system. If the message is displayed
immediately after starting the vehicle or the
message appears while driving, the Supplemental
Brake Assist system needs service. See your
dealer. SeeBrake System Warning Light on
page 254for additional information.
SERVICE BRAKE SYSTEM
If there is a problem with the brake system, this
message will be displayed on the DIC. If this
message appears, stop as soon as possible and
turn off the vehicle. Restart the vehicle and
check for the message on the DIC display. If the
message is still displayed or appears again
when you begin driving, the brake system needs
service. See your dealer.
278

TRANSMISSION HOT
Notice:If you drive your vehicle while the
transmission uid is overheating and the
transmission temperature warning is displayed
on the instrument panel cluster and/or DIC,
you can damage the transmission. This could
lead to costly repairs that would not be
covered by your warranty. Do not drive your
vehicle with overheated transmission uid
or while the transmission temperature warning
is displayed.
If the transmission uid temperature becomes
high, this message will appear on the DIC display.
When the transmission enters the protection
mode, you may notice a change in the
transmission shifting patterns. When the
transmission uid temperature returns to normal,
the display will turn off and the transmission
shifting patterns will return to normal.If the vehicle has the Tow/Haul mode, use this
feature if the transmission is operating at higher
temperatures and/or the following situations
exist, which can cause the transmission to operate
at higher temperatures:
Towing a trailer
Hot outside air temperatures
Hauling a large or heavy load
Over-loading
Low transmission uid level
High transmission uid level
Restricted air ow to the radiator and the
auxiliary transmission oil cooler
A temporary solution to hotter transmission
operating temperatures may be to let the
transmission cool down. If the transmission is
operated at higher temperatures on a frequent
basis, seeScheduled Maintenance (Gasoline
Engine) on page 617for the transmission
your vehicle is equipped with for the proper
transmission maintenance intervals. Also see
Transmission Temperature Gage on page 257for
more information.
280

Setting the Tone (Bass/Treble)
AUDIO:To adjust bass or treble, press and
release AUDIO until BAS (bass) or TRE (treble)
appears on the display. Then press and hold
the up or the down arrow to increase or to
decrease. If a station is weak or has static,
decrease the treble.
To adjust bass or treble to the middle position,
select BAS or TRE. Then press and hold AUDIO
for more than two seconds until you hear a
beep. B (balance) and a zero or T (treble) and a
zero appears on the display.
To adjust both tone controls and both speaker
controls to the middle position, rst end out of audio
mode by pressing another button, causing the radio
to perform that function or wait ve seconds for the
display to return to time of day. Then press and hold
AUDIO for more than two seconds until you hear a
beep. CEN (center) appears on the display.
Adjusting the Speakers (Balance/Fade)
AUDIO:To adjust the balance between the right
and the left speakers, press and release AUDIO
until BAL (balance) appears on the display. Then
press and hold the up or the down arrow to move
the sound toward the right or the left speakers.
To adjust the fade between the front and the rear
speakers, press and release AUDIO until FAD
(fade) appears on the display. Then press and hold
the up or the down arrow to move the sound toward
the front or the rear speakers.
To adjust balance or fade to the middle position,
select BAL or FAD. Then press and hold AUDIO for
more than two seconds until you hear a beep.
B (balance) and a zero or F (fade) and a zero
appears on the display.
To adjust both tone controls and both speaker
controls to the middle position, rst end out of audio
mode by pressing another button, causing the radio
to perform that function or wait ve seconds for the
display to return to time of day. Then press and hold
AUDIO for more than two seconds until you hear a
beep. CEN (center) appears on the display.
Fade may not be available if the vehicle is a regular
cab model.
293

Setting the Tone (Bass/Treble)
AUDIO:Push and release the AUDIO knob until
BASS or TREB (treble) appears on the display.
Turn the knob to increase or to decrease.
The display will show the bass or treble level. If a
station is weak or noisy, decrease the treble.
To adjust the bass or treble to the middle position,
while it is displayed, push and hold the AUDIO
knob. The radio will produce one beep and adjust
the display level to the middle position.
To adjust all tone and speaker controls to the
middle position, push and hold the AUDIO knob
when no tone or speaker control is displayed. ALL
CENTERED will appear on the display, you will
hear a beep, and the display level will be adjusted
to the middle position.
AUTO EQ (Automatic Equalization):Press this
button to select customized equalization settings
designed for country/western, jazz, talk, pop, rock,
and classical. Selecting CUSTOM or changing
bass or treble, returns the EQ to the manual bass
and treble settings.The radio will save separate AUTO EQ settings
for each preset and source.
If the radio is equipped with the Bose®audio
system, the equalization settings are either
CUSTOM or TALK.
Adjusting the Speakers (Balance/Fade)
AUDIO:To adjust the balance between the
right and the left speakers, push and release the
AUDIO knob until BAL (balance) appears on
the display. Turn the knob to move the sound
toward the right or the left speakers.
To adjust the fade between the front and the rear
speakers, push and release the AUDIO knob
until FADE appears on the display. Turn the knob
to move the sound toward the front or the rear
speakers.
To adjust the balance or fade to the middle
position, while it is displayed, push the AUDIO
knob, then push it again and hold it until the radio
produces one beep. The balance or fade will
be adjusted to the middle position and the display
will show the speaker balance.
298

Setting the Tone (Bass/Treble)
AUDIO:Push and release the AUDIO knob until
BASS or TREB (treble) appears on the display.
Turn the knob to increase or to decrease.
The display will show the bass or treble level. If a
station is weak or noisy, decrease the treble.
To adjust the bass or treble to the middle position
while it is displayed, push and hold the AUDIO
knob. The radio will produce one beep and adjust
the display level to the middle position.
To adjust all tone and speaker controls to the
middle position, push and hold the AUDIO knob
when no tone or speaker control is displayed. ALL
CENTERED will appear on the display, you will
hear a beep, and the display level will be adjusted
to the middle position.AUTO EQ (Automatic Equalization):Press this
button to select customized equalization settings
designed for country/western, jazz, talk, pop, rock,
and classical. Selecting CUSTOM or changing
bass or treble, returns the EQ to the manual bass
and treble settings.
The radio will save separate AUTO EQ settings
for each preset and source.
If the radio is equipped with the Bose
®audio
system, the equalization settings are either
CUSTOM or TALK.
Adjusting the Speakers (Balance/Fade)
AUDIO:To adjust the balance between the
right and the left speakers, push and release the
AUDIO knob until BAL (balance) appears on
the display. Turn the knob to move the sound
toward the right or the left speakers.
To adjust the fade between the front and the rear
speakers, push and release the AUDIO knob
until FADE appears on the display. Turn the knob
to move the sound toward the front or the rear
speakers.
308

AUTO EQ (Automatic Equalization):Press this
button to select customized equalization settings
designed for country/western, jazz, talk, pop, rock,
and classical.
The radio will save separate AUTO EQ settings
for each preset and source.
If the radio is equipped with the Bose
®audio
system, the equalization settings are either
CUSTOM or TALK.
Adjusting the Speakers (Balance/Fade)
AUDIO:To adjust the balance between the
right and the left speakers, push and release the
AUDIO knob until BAL (balance) appears on
the display. Turn the knob to move the sound
toward the right or the left speakers.
To adjust the fade between the front and rear
speakers, push and release the AUDIO knob until
FAD (fade) appears on the display. Turn the
knob to move the sound toward the front or the
rear speakers.
To adjust the balance or fade to the middle
position while it is displayed, push and hold the
AUDIO knob. The radio will produce one beep and
adjust the display level to the middle position.To adjust all tone and speaker controls to the
middle position, push and hold the AUDIO knob
when no tone or speaker controls are displayed.
ALL CENTERED will appear on the display
and you will hear a beep.
Finding a Program Type (PTY) Station
(RDS and XM™)
To select and nd a desired PTY perform the
following:
1. Press the TYPE button to activate program
type select mode. P-TYPE and the last
selected PTY will appear on the display.
2. Turn the TYPE knob or press and release the
TYPE button to select a PTY.
3. Once the desired PTY is displayed, press
either the TYPE or the SEEK arrows to
select and to take you to the PTY’s rst
station.
4. To go to another station within that PTY,
press the TYPE button then, press either
the TYPE or the SEEK arrows once. If
the PTY is not displayed, go back to Step 1.
5. Press either the TYPE or the SEEK arrows
twice to exit program type select mode.
322