key GMC C-SERIES 1999 Owners Manual

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Safety Belt Use During Pregnancy
Safety belts work for everyone, including pregnant
women. Like all occupants, they are more likely to be
seriously injured if they don't wear safety belts.
A pregnant woman should wear a lap-shoulder belt, and
the lap portion should be worn as low as possible, below
the rounding, throughout the pregnancy.The best way to protect the fetus is to protect the
mother. When a safety belt is worn properly, it's more
likely that the fetus won't be hurt in a crash. For
pregnant women, as for anyone, the key to making
safety belts effective is wearing them properly.
Right Passenger Position
The right passenger's safety belt works the same way as
the driver's safety belt. See ªDriver Positionº earlier in
this section.
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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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Keys
CAUTION:
Leaving children in a vehicle with the ignition
key is dangerous for many reasons. A child or
others could be badly injured or even killed.
They could operate the controls or even make the
vehicle move. Don't leave the keys in a vehicle
with children.
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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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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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NOTICE: (Continued)

Use the lowest gear you can when you start
a loaded vehicle in motion and when going
up hills to avoid overloading the engine.

Check and adjust engine and transmission
fluid levels often and be sure tires are properly
inflated for the load you're carrying.

If you have a Caterpillar
 diesel engine,
see the Caterpillar Operation &
Maintenance Manual.
Ignition Positions
CAUTION:
Leaving children in a vehicle with the ignition
key is dangerous for many reasons. A child or
others could be injured or even killed. They could
operate power windows or other controls or even
make the vehicle move. Don't leave the keys in
the vehicle with children.
Use your square-head key to start your vehicle (unless it
has the single
-key option, where one oval-head key
works everything, including the ignition). You can turn
the ignition switch to five different positions.
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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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2-8 Manual Transmission
Set the parking brake, shift your gear selector to
NEUTRAL and hold the clutch pedal to the floor while
starting the engine.
Starter Motor Operation
1. The starter motor will disengage if you release
the key or the engine reaches a predetermined
engine speed.
2. To prevent overheating, the starter motor will
disengage after continuously operating for 15 seconds.
You must release the key from the start position to
re
-engage the starter.
3. The starter motor will not engage if the engine is
already running.
4. The starter motor will disengage if, after two
seconds, the starter pinion gear does not engage the
flywheel or there is no engine rpm signal from the
engine speed sensor.
Starting Your Engine
1. Without pushing the accelerator pedal, turn your
ignition key to START. When the engine starts, let
go of the key. The idle speed will go down as your
engine gets warm.
2. If the engine doesn't start in 10 seconds, push the
accelerator pedal all the way down and crank the
engine for five more seconds, unless it starts sooner.
3. If your engine still won't start (or starts but then
stops), it could be flooded with too much gasoline.
Wait 15 seconds to let the starter motor cool down.
Do Steps 1 through 3 again.
When the engine starts, let go of the key and the
accelerator pedal.
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Starting Your Diesel Engine
If you have a Caterpillar diesel engine, also refer to
your Caterpillar
Operation & Maintenance Manual for
starting procedure.
To make starting easier in cold weather (below 32F or
0C), the proper viscosity engine oil should be used. It's
also best to heat the engine oil first. You can do this by
using an engine coolant heater. A GM Automatic Ether
Injection System aids cold weather starting.
NOTICE:
Your diesel engine has an electric air intake
heater system which reduces white smoke and
helps start the engine in cold weather. Do not
spray starting fluid into the air intake where it
can contact the heater elements.
If you don't have the GM Automatic Ether
Injection System, don't use starting fluid or
you could damage your engine. If you have the
GM system, use only GM approved starting fluid
that has been tested to establish compatibility
with the air inlet heater system.
NOTICE:
If you ever have to have your vehicle towed, see
the part of this manual that tells how to do it
without damaging your vehicle. See ªTowing
Your Vehicleº in the Index.
Restarting the Diesel Engine While Moving
(Automatic Transmission)
If you have to restart the engine while the vehicle is
moving, you'll first have to shift the automatic transmission
to NEUTRAL (N). This safety feature prevents starting
the engine when the transmission is in a drive gear.
Stopping the Diesel Engine
If you have a Caterpillar diesel engine, see your
Caterpillar
Operation & Maintenance Manual.
1. Set the parking brake and shift to NEUTRAL (N) or
PARK (P).
2. Turn the ignition switch key to OFF.
If your vehicle has a two
-speed axle, see ªRear Axle,
Tw o
-Speed Electric Shift Controlº or ªRear Axle,
Tw o
-Speed Airshift Controlº in the Index.
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The charging system light should come on when the
ignition switch key is turned to RUN or START and
should go out when the engine is running above idle.
If the light doesn't go out or comes back on during
normal engine operation, have the charging system
checked right away. (This light tells you if the
generator is not charging; it doesn't reflect the
condition of the battery.)

The voltmeter charge indicator gage tells you the
condition of your battery's charge. The gage should
be in the center area during engine operation. The
red area on the left indicates an undercharge
condition; the red area on the right indicates an
overcharge. If the gage is in either red area, have the
battery and charging system checked right away.
NOTICE:
Don't allow the engine to operate at low idle for
more than five minutes. This can cause low
engine operating temperatures which can affect
engine operation and reduce engine life. Engine
idle speed should be increased to 1200 rpm
whenever extended idle is required. Once started,
the engine should be placed under load to allow
the engine coolant temperature to reach
150F (66C) before shutting off the engine.
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