1999 GMC C-SERIES heater

2-
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2-1
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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2-7
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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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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2-11 Cold Weather Starting (Caterpillar

Diesel)
Because the diesel engine uses compression ignition, it
is harder to start in cold weather than a gasoline engine.
The air intake heater and use of the proper engine oil,
optional engine coolant heaters and optional ether
injection systems help cold weather starting. See the
Caterpillar

Operation & Maintenance Manual for
more information.
Diesel Engine Warm-Up
Several factors affect how quickly your diesel engine
warms up. These can include outside temperature,
engine load, idle time and your vehicle's option content.
Your vehicle may be equipped with some features that
can help the engine reach operating temperature sooner.
Some of these features are discussed below.
Also, remember that an automatic transmission adds
heat to the cooling system through the heat exchanger in
the radiator. Because of this, vehicles equipped with
automatic transmissions are often able to retain engine
coolant heat better than manual transmission vehicles.
See your Caterpillar

Operation & Maintenance manual
for additional diesel engine warm
-up information.
Engine Automatic Shutdown (If Equipped)
Your CHECK GAGES light will come on if the system
senses high engine temperature or low engine oil
pressure. If high engine temperature is detected, you
will also hear a tone alarm at two beats per second. The
alarm and the light will remain on until the condition is
fixed. If the engine temperature condition worsens, the
tone alarm will go to five beats per second. When a low
oil pressure condition is detected, the five beat per
second alarm will come on immediately.
If the system senses low engine coolant, the five beat
per second alarm and the LOW COOLANT warning
light will come on.
The five beats per second tone alarm means that your
engine will shut down in 25 seconds. Pull off the road
and shut off the engine. Don't start it until the reason for
the problem is known, and the problem is fixed. If the
engine shuts down when you are still in traffic, you can
restart the engine and get another 25 seconds of
operation. Do this only if you have to, since there is a
problem that can harm the engine if it isn't fixed.
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2-15
Engine Coolant Heater (If Equipped)
If your vehicle has this
feature, the plug
-in
receptacle is located behind
the front bumper as shown,
or in the component box
on the driver's side of
the vehicle.
In very cold weather, 0
F (
-18
C) or colder, the engine
coolant heater can help. You'll get easier starting and
better fuel economy during engine warm
-up. Usually,
the coolant heater should be plugged in a minimum of
four hours prior to starting your vehicle.
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Find the plug
-in receptacle (either behind the front
bumper or in the component box).
3. Plug a heavy
-duty, three-prong extension cord
(rated for at least 15 amps) into the vehicle's plug
-in
receptacle first. Then plug the extension cord into a
normal, grounded 110
-volt AC outlet.
CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the wrong
kind of extension cord could overheat and cause
a fire. You could be seriously injured. Plug the
cord into a properly grounded three
-prong
11 0
-volt AC outlet. Use a heavy-duty three-prong
extension cord rated for at least 15 amps.
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2-16
4. Before starting the engine, be sure to unplug the cord.
How long should you keep the coolant heater plugged
in? The answer depends on the outside temperature.
Above 32
F (0
C), the coolant heater is not required.
From 32
F to
-10
F (0
C to -23
C), keep the
coolant heater plugged in at least two hours. Below
-10
F (-23
C), keep the coolant heater plugged in for
a minimum of eight hours or overnight. It will not harm
either the coolant heater or the vehicle to leave the
coolant heater plugged in longer than the times stated.
Be sure to remove and store the cord before starting the
engine. See ªDiesel Fuel Requirements and Fuel
Systemº in the Index for information on what fuel to use
in cold weather.
Diesel Engine Exhaust Brake
The exhaust brake is available on vehicles equipped
with a diesel engine and air brakes (or an air
compressor). It is located in the exhaust system.
The switch is on the upper
right side of the instrument
panel and turns the exhaust
brake on and off.
The exhaust brake indicator light is on when the exhaust
brake is in use.
The exhaust brake is used to help slow the vehicle and
may assist the vehicle's foundation brakes. The use of the
exhaust brake will assist the braking of the vehicle and
prolong the life of the foundation brake lining material.
When using the exhaust brake, the proper gear range
selection is important. The exhaust brake will be most
effective if the gear range selected is the lowest possible
range that does not allow the engine rpm to go more than
200 rpm above rated (full load) rpm as shown on the
Engine Information Plate. (Do not exceed 2900 rpm.)
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2-47 Heated Outside Mirrors (If Equipped)
If your vehicle has heated
mirrors, you'll find this
switch on the upper right
side of your instrument
panel area, just above the
radio. Use it to operate your
mirror heaters to defrost or
defog your mirrors.
When you turn on the mirror heaters, an indicator light
in the switch will be lit to tell you the heaters are on.
Once the mirrors are clear for viewing, turn the switch
off. The mirror heaters remain on until the heater switch
or ignition switch is turned off. However, when you turn
the ignition back on, the heater switch will again be on
until turned off.
Ashtray and Cigarette Lighter
(If Equipped)
The ashtray is just below the gages on the right side of
your instrument panel. If you have a cigarette lighter, it
is inside the ashtray.
To use the lighter, press it in all the way and let go.
When it's ready, it will pop back by itself.
NOTICE:
Don't hold a cigarette lighter in with your hand
while it is heating. If you do, it won't be able to
back away from the heating element when it's
ready. That can make it overheat, damaging the
lighter and heating element.
To remove the ashtray for cleaning, pull up on the
front of it.
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2-63 Intake Heater Indicator Light
(Diesel Engines)
This light on the instrument
panel will come on when
the intake heater is on and
the ignition key is in ON.
Since the light is illuminated whenever the intake heater
is activated, it is normal for the light to cycle on and off
as the heater cycles during engine warm
-up. See
ªEngine Startingº in your Caterpillar
Operation &
Maintenance Manual for more information.
Diff Lock Indicator Light (If Equipped)
This light on the instrument
panel is on when the
inter
-axle differential lock
system is in use.
The light will come on momentarily during starting.
If the light fails to come on, have it repaired as soon as
possible so you will be aware when the lock system is
in use.
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