1999 GMC C-SERIES lock

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Bench (A)Suspension (B)
To unlatch the belt, just push the button on the buckle.
The belt should go back out of the way. For a
suspension
-type seat, if the belt is pulled out all the way
so that it locks, press down on the button on the retractor
cover to make it retract.
Before you close the door, be sure the belt is out of the
way. If you slam the door on it, you can damage both the
belt and your vehicle.
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Section 2 Features and Controls
Here you can learn about the many standard and optional features on your vehicle, and information on starting,
shifting and braking. Also explained are the instrument panel and the warning systems that tell you if everything is
working properly
-- and what to do if you have a problem.
2
-2 Keys
2
-4 Door Locks
2
-5 Theft
2
-5 New Vehicle ªBreak-Inº
2
-6 Ignition Positions
2
-7 Starting Your Gasoline Engine
2
-10 Starting Your Diesel Engine
2
-13 Engine Checks Before Operating
2
-15 Engine Coolant Heater (If Equipped)
2
-16 Diesel Engine Exhaust Brake
2
-17 Two-Speed Rear Axle Electric Shift Control
(If Equipped)
2
-20 Automatic Transmission Operation
2
-22 Manual Transmission Operation
2
-23 Parking
2
-29 Parking Over Things That Burn
2
-29 Engine Exhaust2
-30 Running Your Engine While You're Parked
(Automatic Transmission)
2
-30 Windows
2
-31 Tilt Wheel (If Equipped)
2
-32 Turn Signal/Multifunction Lever
2
-39 Trailer Brake Hand Control Valve (Option)
2
-40 Inter-Axle Differential Lock Control
(If Equipped)
2
-41 Rear Axle Differential Lock Control
(If Equipped)
2
-42 Engine Air Control (If Equipped)
2
-43 Exterior Lamps
2
-46 Interior Lamps
2
-46 Mirrors
2
-50 Instrument Panel
2
-52 Instrument Panel Cluster
2
-55 Warning Lights, Gages and Indicators
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The square-head key is for
the ignition switch only.
The oval-head key is for
the doors.If you have the optional one
-key system, the oval key
will operate all locks, including the ignition switch.
When a new vehicle is delivered, the dealer removes the
plugs from the keys and gives them to the first owner.
Each plug has a code on it that tells your dealer or a
qualified locksmith how to make extra keys. Keep the
plugs in a safe place. If you lose your keys, you'll be
able to have new ones made easily using this code.
NOTICE:
Your vehicle has a number of new features that
can help prevent theft. But you can have a lot of
trouble getting into your vehicle if you ever lock
your keys inside. You may even have to damage
your vehicle to get in. So be sure you have
extra keys.
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Door Locks
CAUTION:
Unlocked doors can be dangerous.
Passengers -- especially children -- can easily
open the doors and fall out. When a door is
locked, the inside handle won't open it.
Outsiders can easily enter through an unlocked
door when you slow down or stop your vehicle.
This may not be so obvious: You increase the
chance of being thrown out of the vehicle in a
crash if the doors aren't locked. Wear safety belts
properly, lock your doors, and you will be far
better off whenever you drive your vehicle.
To lock your door from
the inside, slide the lock
control down.
To unlock the door, slide the lock control up.
Power Door Locks (If Equipped)
Push the switch marked
LOCK to lock both doors
at once.
Push the switch marked UNLOCK to unlock both doors.
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2-5 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.
Theft
Vehicle theft is big business, especially in some cities,
and even commercial vehicles are no exception. 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.
Remember to remove your key and take it with you.
Always do this. When you take your key with you, your
ignition will be locked. Also remember to lock the doors.
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:

Let your engine warm up before you
operate your vehicle under load.

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.
NOTICE: (Continued)
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ACCESSORY (A): This position lets you use
accessories when the engine is off. To use
ACCESSORY, push in the key and turn it toward you.
LOCK (B): This position locks your ignition. You will
be able to remove your key only when the switch is in
this position.
OFF (C): This position lets you turn off the engine, but
the key can't be removed.
RUN (D): This is the position for driving and activating
the CAT diesel air inlet heater (if equipped).
START (E): This position starts your engine.
Engine Starter Over-Crank Protection
(If Equipped)
Some vehicles have an engine starter over-crank
protection system. This system includes a built
-in
temperature limiting switch to prevent internal damage
to the starter. If the starter motor overheats and shuts
off due to over
-cranking, the motor must cool down
before the switch will reset and allow you to operate the
starter. It can take up to six minutes before the starter
will work again.
Starting Your Gasoline Engine
Engines start differently. The 8th digit of your Vehicle
Identification Number (VIN) shows the code letter for
your engine. (See ªVehicle Identification Numberº in
the Index.) Follow the proper steps to start the engine.
To start a diesel engine, see ªStarting Your Diesel
Engineº in the Index.
Automatic Transmission
Set the parking brake and move your shift lever to
NEUTRAL (N) or PARK (P) if so equipped. Your
engine won't start in any other position
-- that's a
safety feature.
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The manual fast idle feature is activated by pressing the
switch on the instrument panel. When the switch is
pressed again, or any of the previous conditions are not
met, manual fast idle will be deactivated.
Manual fast idle can be used to set any desired idle
speed. To set a new temporary engine idle speed:
1. Make sure all of the previously described conditions
are met.
2. Press the accelerator pedal to the desired engine speed.
3. Momentarily press the manual FAST IDLE switch.
The temporary idle speed will be set. This new rpm
level will be remembered by the system until either the
ignition is turned to OFF or a new idle speed is set.
Radiator Shutters -- Caterpillar

(If Equipped)
Radiator shutters aid engine warm-up by blocking the
airflow through the radiator and charge the air cooler to
conserve heat in cold conditions.
The radiator shutters on your vehicle (if equipped)
operate automatically. When the ignition switch is in
RUN or START and the engine temperature is below
195F (90C), the shutters will close, blocking the flow
of air through the radiator and charge the air cooler.When the engine temperature reaches 195F (90C), the
shutters will open to the normal operating position.
Engine Checks Before Operating
When you've started your engine, let it run for 20 to
30 seconds before you put a load on the engine.
But don't leave the vehicle while the engine is running.
During this warm
-up period, check your warning lights
and gages:

If oil pressure doesn't begin to rise within 15 seconds
of starting, stop the engine and find the cause.

If the engine coolant temperature gage needle goes
into the hot area on the gage, stop the engine and
find the cause of the overheating.

If you have air brakes, the dual
-needle air pressure
gage should read at least 105 psi (720 kPa) for both
service systems before you try to move the vehicle.
When air pressure is below 60 psi (420 kPa), the
LOW AIR light will come on and you will hear a
tone alarm. If the pressure doesn't build up or drops
during warm
-up, stop the engine and find the cause
before you try to move the vehicle. Recommended
air pressure before actually driving away is
120 psi (830 kPa).
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The accelerator and clutch pedals must be released in
order for the exhaust brake to engage. Whenever the
exhaust brake is active, the light in the switch will be on.
Do not use the exhaust brake when running the engine at
idle during warm
-up or other extended periods.
Prolonged use of the exhaust brake during idling will
cause the engine to overheat.
CAUTION:
Be careful when using the exhaust brake or you
could lock the wheels and lose control of the
vehicle. Operators not familiar with an exhaust
brake should not use this brake on slippery
surfaces before learning to use it on dry surfaces.
If the vehicle's wheels begin to lock when using
the exhaust brake on slippery surfaces, switch the
exhaust brake off immediately. The exhaust
brake will turn off if the anti
-lock brake system
is activated.
Tw o-Speed Rear Axle Electric Shift
Control (If Equipped)
If your vehicle has this feature, you'll find a label (or
labels) on the ceiling above the windshield or in another
place near the driver that show how to use it. Be sure
to follow the directions carefully. Use the following
directions based on the type of shift control you have.
Automatic Transmission
The switch for the rear axle
shift control is on the shift
tower to the right of the
shift lever.
When the switch is up, the rear axle is in the high range.
Push it down to get the low range.
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