light GMC C-SERIES 1999 Service Manual

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2-67 Daytime Running Lamps (DRL)
Indicator Light
This light is located on the
upper cluster portion of the
instrument panel. It goes on
whenever the Daytime
Running Lamps are on. See
ªDaytime Running Lampsº
in the Index.
When it begins to get dark, the DRL indicator light is a
reminder to turn on your headlamps.
Check Gages Indicator Light (If Equipped)
This light will come on as
you're starting the engine,
just as a check.
If it ever comes on and stays on while you are driving,
however, it means that either your engine coolant
temperature gage or your engine oil pressure gage may
be showing a reading in the warning zone.
When the CHECK GAGES light comes on, you will
also hear a warning tone. The tone and the light will stay
activated until the problem is corrected.
This light may also come on if your vehicle is equipped
with the optional automatic engine shutdown system and
engine shutdown has begun. See ªEngine Automatic
Shutdownº in the Index.
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2-69 Transmission Temperature Gage
(If Equipped)
If you have an automatic
transmission and this gage,
it is to the right of the dash
mounted shift lever, just to
the right of your
floor
-mounted shift lever or
on the lower portion of the
instrument panel to the right
of the steering wheel.
When your ignition is on, the gage shows the
temperature of the transmission oil. A reading in the
warning zone means you must stop driving and check
into the cause. One possible cause is a low oil level in
the transmission.
NOTICE:
If you drive when the transmission temperature
gage is in the warning zone, you can badly
damage the transmission.
Air Pressure Gage (If Equipped)
If your vehicle has air
brakes, this gage at the
center of your instrument
cluster shows the air
pressure for both your front
and rear brake systems.
If the needle on the gage indicates that the air pressure is
below 60 psi (415 kPa), the LOW AIR warning light
will come on. An alarm will also sound if this happens.
The yellow pointer shows the pressure available for the
front system, while the green pointer shows pressure for
the rear. There should be no more than 4 psi (28 kPa)
difference showing between the systems.
Don't drive until both pointers are showing at least
120 psi (830 kPa), so you'll have enough air if you need
to apply your brakes.
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3-3 Optional Comfort Controls (If Equipped)
If your vehicle has air conditioning, your comfort
controls will look like this.
Your system has a lighted display showing each system
when it is operating. During normal operation, all the
lights won't come on at the same time. Only the ones
displaying the current settings will light.
Temperature Selector Bar
The bar under your system display lets you select the
temperature of the air coming into the passenger area of
your vehicle. Press COLD for cooler air and press HOT
for warmer air. Release the bar when the system reaches
the temperature you want. The temperature is shown on
the display by an arrow moving between C and H.
If your engine is equipped with an engine coolant heater,
you can use it during initial start
-up in cold weather
(20
F (
-8
C) or lower) to help heat the passenger
compartment faster. See ªEngine Coolant Heaterº in
the Index.
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3-4
Left Blend Button
The airflow can be blended between the two positions.
To blend between the positions, press the side of the
button showing the area where you would like more
airflow. The system will automatically begin to blend
toward the position chosen. To stop the system between
positions, just press the same side of the button again.
VENT: Press the top of the button and all of the
airflow will come through the instrument panel vents.
HEATER: Press the bottom of this button and all
of the airflow will come through the floor outlet.
Right Blend Button
The airflow can be blended between the two positions.
To blend between positions, press the side of the button
showing the area where you would like more airflow.
The system will automatically begin to blend toward the
position chosen. To stop the system between positions,
just press the same side of the button again.
DEFOG: This setting operates the defogger. Air
comes out near the bottom of the windshield and at your
front side windows.
HEATER: Press the bottom of this button and
heated air comes out near the floor.A/C Button
Press the A/C button to turn your air conditioner on and
off. The A/C symbol will light on your display, and air
will come out of your instrument panel vents. The fan
will automatically be set on LOW.
MAX Button
If you press the MAX button, the air in your vehicle will
be recirculated. With the air conditioner on, MAX will
give you maximum cooling. It can also be used in all
modes to help keep dust out of your vehicle. When
MAX is selected, REC will light on the display.
Fan Control Button
This button is in the upper passenger's side corner of
your system control panel. The fan has four settings:
low, medium low, medium high and high. Press the top
of the button with the plus symbol to increase airflow.
Press the bottom of the button with the minus symbol to
decrease airflow. The setting you select is shown on
your display as LOW, MED, HI or OFF.
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3-5
OFF
Press this button to turn the air conditioning/heating
system off. Pressing OFF will erase the present mode of
operation from the system's memory. Outside air will
still come out of the heater outlet whenever the vehicle
is moving forward.
If the OFF button is pressed, you must press A/C,
MAX or one of the BLEND buttons to turn the system
back on.
Air Conditioning
When you first turn on your vehicle's air conditioning,
open the windows long enough to clear the vehicle of
hot air, then close them. Using the MAX button can also
help. See ªMAX Buttonº earlier in this section for
more information.
For normal cooling on hot days, use A/C with the
temperature selector toward C.
When you press the A/C button to turn the air
conditioner off, the system will operate in the vent
mode. When you turn the air conditioner back on, the
system will operate in the mode you last selected unless
the OFF button was pressed.If your air conditioner develops high system pressure, it
will automatically go into the MAX mode and REC will
light on your display. The A/C system will remain in the
MAX mode, even if you press the MAX button, until
system pressure returns to a normal level.
Heating
On cold days, use HEATER with the temperature
selector all the way toward H. When the inside of the
vehicle has reached a comfortable temperature, maintain
it by using the temperature selector bar.
If your vehicle is equipped with a diesel engine, and the
engine has been idling for a long time when it's cold
outside, your heater may blow out cool air. This is
normal. When you increase the engine speed under load,
your heater should blow out warmer air. If it doesn't,
your coolant level may be low. See ªEngine Coolantº in
the Index to check your coolant level.
While idling your diesel engine, you can use the MAX
button to recirculate the air in the cab to help maintain
interior heat. This will preserve engine coolant temperature
and cab heat when idling cannot be avoided.
Using the MAX button while driving is not recommended
because interior window fogging can result.
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3-10 Remote Cassette Tape Player (If Equipped)
Your tape player is built to work best with tapes that are
up to 30 to 45 minutes long on each side. Tapes longer
than that are so thin they may not work well in this player.
To load a cassette tape, hold the cassette with the tape to
the right. Then, insert the cassette tape. Tape direction is
displayed by the lighted arrow. To change the tape
direction, press the FF button.
Once the tape is playing, use the control knobs for
VOLUME, BAL, FAD, BAS and TRE just as you do
for the radio.
REW: Press the left arrow to rapidly reverse the tape.
Press FF to stop reversing the tape.FF: Press the right arrow to rapidly advance the tape.
Press REW to stop forwarding the tape.
PROGRAM: An arrow will light on the display to
show which side of the tape is playing.
EJ: Press this button to remove the tape.
There is a space provided with your remote cassette tape
player to keep cassette tapes in.
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.
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3-12 Care of Your Cassette Tape Player
A tape player that is not cleaned regularly can cause
reduced sound quality, ruined cassettes or a damaged
mechanism. Cassette tapes should be stored in their
cases away from contaminants, direct sunlight and
extreme heat. If they aren't, they may not operate
properly or may cause failure of the tape player.
Your tape player should be cleaned regularly after every
50 hours of use. If you notice a reduction in sound
quality, try a known good cassette to see if it is the tape
or the tape player at fault. If this other cassette has no
improvement in sound quality, clean the tape player.
The recommended cleaning method for your cassette
tape player is the use of a scrubbing action,
non
-abrasive cleaning cassette with pads which scrub
the tape head as the hubs of the cleaner cassette turn.
The recommended cleaning cassette is available through
your dealership (GM Part No. 12344789).
When using a scrubbing action, non
-abrasive cleaning
cassette, it is normal for the cassette to eject because
your unit is equipped with a cut tape detection feature
and a cleaning cassette may appear as a broken tape.
If the cleaning cassette ejects, insert the cassette at least
three times to ensure thorough cleaning.You may also choose a non
-scrubbing action, wet-type
cleaner which uses a cassette with a fabric belt to clean
the tape head. This type of cleaning cassette will not
eject on its own. A non
-scrubbing action cleaner may
not clean as thoroughly as the scrubbing type cleaner.
The use of a non
-scrubbing action, dry-type cleaning
cassette is not recommended.
Cassettes are subject to wear and the sound quality may
degrade over time. Always make sure the cassette tape
is in good condition before you have your tape
player serviced.
Fixed Mast Antenna
The fixed mast antenna can withstand most vehicle
washes without being damaged. If the mast should ever
become slightly bent, you can straighten it out by hand.
If the mast is badly bent, as it might be by vandals, you
should replace it.
Check every once in a while to be sure the mast is still
tightened to the cowl.
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4-7
Avoid needless heavy braking. Some people drive in
spurts
-- heavy acceleration followed by heavy
braking
-- rather than keeping pace with traffic. This
is a mistake. Your brakes may not have time to cool
between hard stops. Your brakes will wear out much
faster if you do a lot of heavy braking. If you keep pace
with the traffic and allow realistic following distances,
you will eliminate a lot of unnecessary braking. That
means better braking and longer brake life.
If your engine ever stops while you're driving, brake
normally but don't pump your brakes. If you do, the
pedal may get harder to push down. If your engine
stops, you will still have some power brake assist. But
you will use it when you brake. Once the power assist is
used up, it may take longer to stop and the brake pedal
will be harder to push.
Hydraulic Brake Systems
If your engine stops running, or if your primary brake
system stops working, your vehicle has a reserve power
assist system to help you slow down. Just slowly and
steadily apply the brake pedal until you can safely get
off the road. The pedal will seem harder to push down.
Don't pump the pedal; the system won't work well or at
all that way.You may find that the steering wheel seems hard to turn
when you're turning and braking at the same time. Also,
the PRIMARY BRAKE warning light may come on and
the warning tone may sound. This is normal because the
main hydraulic brake system and power steering both
use the power steering pump. If this ever happens, let up
on the brake pedal a little. When you let up on the brake
pedal in that situation, it lets the steering get a little
more help from the pump.
Anti-Lock Brakes (Option)
Your vehicle may have anti-lock brakes (ABS). ABS is
an advanced electronic braking system that will help
prevent a braking skid.
If your vehicle has anti-lock
brakes, this warning light on
the instrument panel will
come on briefly when you
start your vehicle.
When you start your engine and begin to drive away,
your anti
-lock brake system will check itself. You may
hear a momentary motor or clicking noise while this test
is going on. This is normal.
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4-8
If there's a problem with the anti-lock brake system, the
anti
-lock brake system warning light will stay on. See
ªAnti
-Lock Brake System Warning Lightº in the Index.
Here's how anti-lock works. Let's say the road is wet.
You're driving safely. Suddenly an animal jumps out in
front of you.
You slam on the brakes. Here's what happens with ABS.A computer senses that wheels are slowing down. If one
of the wheels is about to stop rolling, the computer will
separately work the brakes at each wheel.
The anti
-lock system can change the brake pressure
faster than any driver could. The computer is
programmed to make the most of available tire and
road conditions.
You can steer around the obstacle while braking hard.
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4-12
Off-Road Recovery
You may find that your right wheels have dropped off the
edge of a road onto the shoulder while you're driving.
If the level of the shoulder is only slightly below the
pavement, recovery should be fairly easy. Ease off the
accelerator and then, if there is nothing in the way, steer so
that your vehicle straddles the edge of the pavement. You
can turn the steering wheel up to one
-quarter turn until the
right front tire contacts the pavement edge. Then turn your
steering wheel to go straight down the roadway.
Passing
The driver of a vehicle about to pass another on a
two
-lane highway waits for just the right moment,
accelerates, moves around the vehicle ahead, then goes
back into the right lane again. A simple maneuver?
Not necessarily! Passing another vehicle on a two
-lane
highway is a potentially dangerous move, since the
passing vehicle occupies the same lane as oncoming
traffic for several seconds. A miscalculation, an error in
judgment, or a brief surrender to frustration or anger can
suddenly put the passing driver face to face with the
worst of all traffic accidents
-- the head-on collision.
So here are some tips for passing:

A vehicle like yours takes a longer time to reach
passing speed, so you'll need a longer stretch of clear
road ahead than you would with a passenger car.

ªDrive ahead.º Look down the road, to the sides and to
crossroads for situations that might affect your passing
patterns. If you have any doubt whatsoever about
making a successful pass, wait for a better time.
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