ECU GMC SIERRA 1999 Owner's Guide

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6. To tighten the belt, feed the lap belt back into the
retractor while you push down on the child restraint.
If you're using a forward
-facing child restraint, you
may find it helpful to use your knee to push down on
the child restraint as you tighten the belt.
7. Push and pull the child restraint in different
directions to be sure it is secure.To remove the child restraint, just unbuckle the vehicle's
safety belt and let it go back all the way. The safety belt
will move freely again and be ready to work for an adult
or larger child passenger.
If your vehicle has air bags, turn on the right front
passenger's air bag when you remove the rear
-facing
child restraint from the vehicle, unless the person who
will be sitting there is a member of a passenger air bag
risk group. See ªAIR BAG OFF Switchº in the Index.
CAUTION:
If the right front passenger's air bag is turned off
for a person who isn't in a risk group identified
by the national government, that person 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. Don't turn
off the passenger's air bag unless the person
sitting there is in a risk group. See ªAIR BAG
OFF Switchº in the Index for more on this,
including important safety information.

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Your vehicle has one
double
-sided key for the
ignition and all door locks.
If you ever lose your keys, your dealer will be able to
assist you with obtaining new ones.
NOTICE:
Your vehicle has a number of new features that
can help prevent theft. You can have a lot of
trouble getting into your vehicle if you ever lock
your key inside. You may even have to damage
your vehicle to get in. So be sure you have an
extra key.
Tailgate
You can open the tailgate by lifting up on its handle
while pulling the tailgate toward you.
To shut the tailgate, firmly push it away from you into
the latch.
After you put the tailgate back up, pull it back toward
you to be sure that it latches securely.
Tailgate Removal
The tailgate on your vehicle can be removed to allow for
different loading situations. Although the tailgate can be
removed without assistance, you may want someone to
assist you with the removal to avoid possible damage to
the vehicle.

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To remove the tailgate:
1. Raise the tailgate
slightly and release both
retaining cable clips. To
release the retaining
cable clips, pull the
retaining cable clip
away from the cable
end. Lift the cable so
it points straight out
and push the cable
clips forward.
2. 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.
Reverse the above procedure to reinstall. Make sure the
tailgate is secure.
Third Door (If Equipped)
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 third door to open it.
You must close and latch the third door before you can
close the front passenger door.

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Resynchronization
Resynchronization 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.
Key in the Ignition
If you leave your vehicle with the keys inside, it's an
easy target for joy riders or professional thieves
-- so
don't do it.When you park your vehicle and open the driver's door,
you'll hear a tone reminding you to remove your key
from the ignition and take it with you. Always do this.
Your steering wheel will be locked, and so will your
ignition. If you have an automatic transmission, taking
your key out also locks your transmission. Also
remember to lock the doors.
Parking at Night
Park in a lighted spot, close all windows and lock your
vehicle. Remember to keep your valuables out of sight.
Put them in a storage area, or take them with you.
Parking Lots
If you park in a lot where someone will be watching
your vehicle, it's best to lock it up and take your keys.
But what if you have to leave your ignition key? What if
you have to leave something valuable in your vehicle?

Put your valuables in a storage area, like your
glove box.

If your vehicle has a remote keyless entry system,
take the transmitter with you.

Lock all the doors except the driver's.

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Passlock
Your vehicle is equipped with the Passlock
theft
-deterrent system.
Passlock is a passive theft
-deterrent system. Passlock
enables fuel if the ignition lock cylinder is turned with a
valid key. If a correct key is not used or the ignition lock
cylinder is tampered with, fuel is disabled.
During normal operation, the SECURITY light will go
off approximately five seconds after the key is turned to
the RUN ignition position.
If the engine stalls and the SECURITY light flashes,
wait until the light stops flashing before trying to restart
the engine. Remember to release the key from START
as soon as the engine starts.
If the engine is running and the SECURITY light comes
on, you will be able to restart the engine if you turn the
engine off. However, your Passlock system is not working
properly and must be serviced by your dealer. Your vehicle
is not protected by Passlock at this time. You may also
want to check the fuse (see ªFuses and Circuit Breakersº
in the Index). See your dealer for service.
In an emergency, call the GM Roadside
Assistance Center.
New Vehicle ªBreak-Inº
NOTICE:
Your vehicle doesn't need an elaborate
ªbreak
-in.º But it will perform better in the
long run if you follow these guidelines:

Keep your speed at 55 mph (88 km/h) or
less for the first 500 miles (805 km).

Don't drive at any one speed
-- fast or
slow
-- for the first 500 miles (805 km).
Don't make full
-throttle starts.

Avoid making hard stops for the first
200 miles (322 km) or so. During this time
your new brake linings aren't yet broken
in. Hard stops with new linings can mean
premature wear and earlier replacement.
Follow this breaking
-in guideline every
time you get new brake linings.

Don't tow a trailer during break
-in.
See ªTowing a Trailerº in the Index for
more information.

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CAUTION:
If the right front passenger's air bag is turned off
for a person who isn't in a risk group identified
by the national government, that person 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. Don't turn
off the passenger's air bag unless the person
sitting there is in a risk group. See ªAIR BAG
OFF Switchº in the Index for more on this,
including important safety information.
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 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.

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NOTICE:
Damage to your engine from neglected oil
problems can be costly and is not covered by
your warranty.
Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but readings above the
low pressure zone indicate the normal operating range.
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 your oil as soon as possible.
Security Light
This light will come on
briefly when you turn
the key to START.
The light will come on for five seconds after the key is
turned to ON and then go off. If the light flashes, the
Passlock

System has entered a tamper mode. If the
vehicle fails to start, see ªPasslockº in
the Index.
If the light comes on continuously while driving and
stays on, there may be a problem with the Passlock
System. Your vehicle will not be protected by Passlock,
and you should see your GM dealer.

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3-21 Remote Compact 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.

It is dirty, scratched or wet.

There's too much moisture in the air. (Wait about an
hour and try again.)

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. Write down any three or four
-digit number from
000 to 1999 and keep it in a safe place separate
from the vehicle.
2. Turn the ignition to ACCESSORY or RUN.
3. Turn the radio off.
4. 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.
5. Press MN and 000 will appear on the display.
6. Press MN again to make the last two digits agree
with your code.
7. 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
LED 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. Turn the ignition on. LOC will appear on the display.
2. Press MN and 000 will appear on the display.
3. Press MN again to make the last two digits agree
with your code.
4. Press HR to make the first one or two digits agree
with your code.
5. 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 than
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 ªUnlocking the
Theft
-Deterrent Feature After a Power Lossº earlier in
this section.
Understanding Radio Reception
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.
FM Stereo
FM stereo will give you the best sound, but FM signals
will reach only about 10 to 40 miles (16 to 65 km). Tall
buildings or hills can interfere with FM signals, causing
the sound to come and go.