1997 GMC SIERRA ECU

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To remove the tailgate:
Raise the tailgate
slightly and release both
retaining cable clips.
To
release the cable clips,
lift the cable
so it points
straight out and push the
cable clips forward.
With the tailgate at a
slight upward angle, pull
back on the tailgate at
the right edge and then move the tailgate to
the right to release
the left edge.
Third Door (If Equipped)
Reverse the above procedure to reinstall. Make sure the
tailgate is secure. Your
vehicle may be equipped with a third door that
allows easier access to the rear area of an extended cab.
To open the third door, first open the passenger's side
front door. Then, use the handle located on the front
edge of the rear door to open it. You must close and latch the third door before you can
close the front passenger door.
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Power Door Locks (If Equipped)
Press the bottom of the
power door lock switch,
marked
LOCK, on either
front door to lock all the
doors at once. Press the
ribbed side of the switch to
unlock all the doors at once.
Zear Door Security Locks (Crew Cab)
With this feature, you can
lock the rear doors
so they
can’t be opened from the
inside by the passengers.
Move the lever up
to engage the security feature.
Move the lever down
to return the door locks to
normal operation.
Leaving Your Vehicle
If you are leaving the vehicle, take your keys, open your
door and set the locks from inside. Then get out and
close the door.
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To replace the battery: Synchronization
1. Insert a small coin, or flathead screwdriver, to
separate the bottom of the transmitter from
the top.
making sure the positive
(+) side of the battery is
facing down.
2. Remove the battery and replace it with a new one,
3. Snap the top and bottom together.
4. Test the operation of the transmitter with your
vehicle.
If the transmitter does not work, try
synchronizing the transmitter
with the receiver. Synchronization
may be necessary due to the security
method used
by this system. The transmitter does not
send the same signal twice to the receiver. The receiver
will not respond to a signal it has been sent previously.
This prevents anyone from recording and playing back
the signal from the transmitter.
To resynchronize your transmitter, stand close to your
vehicle and simultaneously press and hold the
LOCK
and UNLOCK buttons on the transmitter for at least
five seconds. The door locks should cycle to confirm
synchronization.
If the locks do not cycle, see your
dealer for service.
Theft
Vehicle theft is big business, especially in some cities.
Although your vehicle has a number of theft-deterrent
features, we know that nothing we put on it can make
it impossible to steal. However, there are ways you
can help.
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AIR BAG OFF Light (Except Crew Cab)
When you turn the right front passenger’s air bag off,
this light will come on and stay on to remind you that
the air bag has been turned off. This light will go off
when
you turn the air bag back on again. See “Securing
a Child Restraint in the Right Front Seat Position” in
the Index for more
on this, including important
safety information.
I A CAUTION:
If the right front passenger’s air bag is turned
off, an adult or a child who is no longer an infant
sitting in the right front passenger’s position
won’t have the extra protection
of an air bag. In
a crash, the air bag wouldn’t be able to inflate
and help protect the person sitting there. Make sure the air bag is turned on unless
you are using
a rear-facing child restraint in the right front
seat position.
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/I CAUTION: I
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 this ever
happens, don’t secure a rearfacing child
restraint in your vehicle until you have your
vehicle serviced.
Charging System Indicator Light
This light should come on
briefly when you
turn on the
ignition, before starting the
engine, as a check to show
you it is working.
After the engine starts, the light should go out.
If it stays
on or comes on while you are driving, you may have a
problem with your charging system. It could indicate a
problem with the generator drive belt, or some other
charging system problem. Have it checked right away.
Driving while this light is on could drain your battery.
If you must drive a
short distance with this light on, it
helps to turn
off all your accessories, such as the radio
and the air conditioner.
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Playing a Compact Disc in the Single Remote Disc
Player
(If Equipped)
If you have this option, you can play one compact disc
(CD) at a time.
To load a CD into the player, hold the disc with the label
side up and insert it carefully into the player
(approximately halfway). The disc will automatically be
pulled into the player.
If the radio is off and the ignition
is on when a CD is inserted, the radio will turn on and
begin playing the CD. It is possible to load and unload
CDs with the ignition
off. To load a disc with the
ignition
off, press the EJECT button on the remote
player and then insert the disc.
To remove the disc, press
the EJECT button and remove the disc from the player.
A disc that has been ejected but is still sitting in the
remote CD player will be pulled back into the player
after approximately
30 seconds. This protects the disc and player from damage. The
disc will not start playing.
To remove the disc, press the EJECT button and remove
the disc from the player.
All
of the compact disc functions are controlled by the
radio buttons except for EJECT. When a disc
is in the
player, a CD symbol will appear
on the display. When a
disc
is playing, the letters CD will appear next to the CD
symbol in the bottom left corner. The track number will
also be displayed.
If the disc comes back
out and ERR appears on the
display, it could be that:
The disc is upside down.
0 It is dirty, scratched or wet.
There’s too much moisture in the air. (Wait about an
hour and try again.)
0 You are driving on a very rough road.
Please contact your dealership if any error recurs or
cannot be corrected.
PREV (1): Press this button to go back to the start
of the current track if more than eight seconds have
played. Press PREV again
to go to the previous track
on the disc.
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Activating the Theft-Deterrent Feature
The instructions which follow, explain how to enter your
secret code to activate the THEFTLOCK system. It is
recommended that you read through all nine steps
before starting the procedure.
NOTE:
If you allow more than 15 seconds to elapse
between any steps, the radio automatically reverts
to
time and you must start the procedure over at Step 4.
1.
2.
3.
4.
5.
6.
1.
Write down any three or four-digit number from
000 to 1999 and keep it in a safe place separate from
the vehicle.
Turn the ignition to ACCESSORY
or RUN.
Turn the radio off.
Press
the 1 and 4 buttons together. Hold them down
until
--- shows on the display. Next you will use the
secret code number which you have written down.
Press MN and
000 will appear on the display.
Press MN again
to make the last two digits agree
with your code.
Press HR to make the first one or two digits agree
with your code.
8. Press AM-FM after you have confirmed that the
code matches the secret code you have written down.
The display will show REP
to let you know that you
need to repeat Steps
5 through 7 to confirm your
secret code.
9. Press AM-FM and this time
the display will show
SEC to let you know that your radio is secure. The
indicator by
the volume control will begin flashing
when the ignition is turned off.
Unlocking the Theft-Deterrent Feature After a
Power
Loss
Enter your secret code as follows; pause no more than
15 seconds between steps:
1.
2.
3.
4.
5.
LOC appears when the ignition is on.
Press MN and
000 will appear on the display.
Press
MN again to make the last two digits agree
with your code.
Press HR to make the first one or two digits agree
with your code.
Press AM-FM after you have confirmed that the
code matches the secret code you have written down.
The display
will show SEC, indicating the radio is
now operable and secure.
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If you enter the wrong code eight times, INOP will
appear on the display. You will have to wait
an hour
with the ignition on before you can try again. When you
try again, you will only have three chances to enter the
correct code before INOP appears.
If you lose or forget your code, contact your dealer.
Disabling the Theft-Deterrent Feature
Enter your secret code as follows; pause no more man
15 seconds between steps:
1. Turn the ignition to ACCESSORY or RUN.
2. Turn the radio off.
3. Press the 1 and 4 buttons together. Hold them down
until
SEC shows on the display.
4. Press MN and 000 will appear on the display.
5. Press MN again to make the last two digits agree
with your code.
6. Press HR to make the first one or two digits agree
with your code.
7. Press AM-FM after you have confirmed that the
code matches the secret code you have written down.
The display will show
---, indicating that the radio is
no longer secured.
If the code entered is incorrect, SEC will appear on the
display. The radio will remain secured until the correct
code
is entered.
When battery power is removed and later applied to a
secured radio,
the radio won’t turn on and LOC will
appear on the display.
To unlock a secured radio, see “Unlocking the
Theft-Deterrent Feature After a Power
Loss” earlier in
this section.
Understanding Radio Reception
FM Stereo
FM stereo will give you the best sound. But FM signals
will reach only about
10 to 40 miles (1 6 to 65 km). Tall
buildings
or hills can interfere with FM signals, causing
the sound to come and go.
AM
The range for most AM stations is greater than for FM,
especially at night. The longer range, however, can
cause stations to interfere with each other. AM can pick
up noise from things like storms and power lines. Try
reducing the treble to reduce this noise if you ever get it.
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