sensor GMC ENVOY 1998 Owners Manual
[x] Cancel search | Manufacturer: GMC, Model Year: 1998, Model line: ENVOY, Model: GMC ENVOY 1998Pages: 386, PDF Size: 20.33 MB
Page 33 of 386

Air bags are designed to inflate only once. After they
inflate, you’ll need
some new parts for your air bag
system. If you don’t get them, the air bag syste,m
won’t be there to help protect you
in another crash.
A new system will include air bag modules and
possibly other parts. The service manual for your
vehicle covers the need to replace other parts.
Your vehicle is equipped with a diagnostic module,
which records information about the air
bag system,
The module records information about the readiness
of the system, when the sensors are activated and
driver’s safety belt usage at deployment.
Let only qualified technicians work on your air bag
system. Improper service can mean that your air
bag
system won’t work properly. See your dealer
for service.
I NOTICE:
If you damage the covering for the driver’s or the
right front passenger’s air bag, the bag may not
work properly.
You may have to replace the air
bag module in the steering wheel or both the air
bag module and the instrument panel for the
right front passenger’s air bag.
Do not open or
break the air bag coverings.
If your vehicle ever gets into a lot of water -- such as
water up to the carpeting or higher -- or if water enters
your vehicle and soaks the carpet, the air bag controller
can be soaked and ruined. If this ever happens, and then
you start your vehicle, the damage could make the air
bags inflate, even if there’s no crash. You would have to
replace
the air bags as well as the sensors and related
parts.
If your vehicle is ever in a flood, or if it’s exposed
to water that soaks the carpet, you can avoid needless
repair costs
by turning off the vehicle immediately.
Don’t let anyone start the vehicle, even to tow
it, unless
the battery cables are first disconnected.
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Page 34 of 386

Servicing Your Air Bag-Equipped Vehicle
Air bags affect how your vehicle should be serviced.
There are parts of the air bag system
in several places
around your vehicle. You don't want the system to
inflate while someone is working
on your vehicle. Your
dealer and the
GM Service Manual have information
about servicing your vehicle and the air bag system.
To
purchase a service manual, see "Service and Owner
Publications"
in the Index.
For up to two mi tes after the ignition key is
turned off and the battery is disconnected, an air
bag can still inflate during improper service. You
can be injured if you are close to an air bag when
it inflates. Avoid wires wrapped with yellow tape
or yellow connectors. They are probably part of
the air bag system.
Be sure to follow proper
service procedures, and make sure the person
performing work for you is qualified to do
so.
~~ ~~ ~~
The air bag system does not nee.d regular maintenance.
Adding Equipment to Your Air
Bag-Equipped
V
Q: If I add a push bumper or a bicycle rack to the
front of my vehicle, will
it keep the air bags
from working properly?
A: As long as the push bumper or bicycle rack is
attached
to your vehicle so that the vehicle's basic
structure isn't changed, it's not likely
to keep the
air bags from working properly
in a crash.
e.' Is there anything I might add to the front of the
vehicle that could keep the air bags from
working properly?
A: Yes. If you add things that change your vehicle's
frame, bumper system, front end sheet metal or
height,
they may keep the air bag system from
working properly. Also, the air bag system may not
work properly
if you relocate any of the air bag
sensors.
If you have any questions about this, you
should contact Customer Assistance before
you
modify your vehicle. (The phone numbers and
addresses for Customer Assistance are
in Step Two of
the Customer Satisfxtion Procedure
in this manual.
See ;'Customer Satisfiction Procedure"
in the Index.)
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Page 98 of 386

Rotate the knob to the right to the master lamps symbol
to turn on all the lamps listed as well as
the headlamps.
Rotate the
knob all the way to the left to turn off your
lamps and put the system in automatic headlamp mode.
Automatic Headlamp System
When it is dark enough outside, your automatic
headlamp system will turn on your headlamps at the
normal brightness along with other lamps such as the
taillamps, sidemarker, parking lamps and the instrument
panel lights. The radio lights will also be dim.
Your vehicle is equipped with High Intensity Discharge
(€€ID) headlamps. Your headlamps come on at lower
intensity and gradually increase to full brightness.
Your vehicle is equipped with
a light sensor on the top
of the instrument panel under the radio speaker grille,
so
be sure it is not covered, which will cause the system to
be on whenever the ignition is on.
The system may also turn on your headlamps when
driving through a parking garage, heavy overcast
weather, a tunnel or fueling your vehicle in a low-light
area. This is normal.
There is a delay in the transition between the daytime
and nighttime operation of the Daytime Running Lamps
(DRL) and the automatic headlamp systems
so that driving under bridges or bright overhead street lights
does not affect the system. The DRL and automatic
headlamp system will only be affected when the light
sensor
sees a change in lighting lasting longer than
the delay.
To idle your vehicle with the automatic headlamp
system
off, set the parking brake while the ignition is
off. Then start your vehicle. The automatic headlamp
system will stay off until you release the parking brake.
As with any vehicle, you should turn on the regular
headlamp system when you need it.
Lamps On Reminder
A reminder chime will sound when your headlamps or
parking lamps
are manually turned on and your ignition
is in
OFF, LOCK or ACCESSORY. To disable the
chime, rotate the thumb wheel all the way down. In
the
automatic mode, the headlamps turn off once the
ignition key is in
OFF,
Daytime Running Lamps
Daytime Running Lamps (DRL) can make it easier for
others to see the front of your vehicle during the day.
DRL can be helpful in many different driving
conditions, but they can be especially helpful in the short periods after dawn and before sunset.
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Page 124 of 386

Air Bag Readiness Light
There is an air bag readiness light on the instrument
panel, which shows
the air bag symbol. The system
checks the air bag’s electrical system for malfunctions.
The light tells you
if there is an electrical problem. The
system check includes
the air bag sensors, the air bag
module, the wiring and the diagnostic module. For more
information
on the air bag system, see “Air Bag” in
the Index.
This light will come on
when you start your engine,
and
it will flash for a few
seconds. Then the light
should go out. This means
the system is ready.
If the air bag readiness light stays on after you start the
engine or comes on when you are driving, your air bag
system may
not work properly. Have your vehicle
serviced right away.
The air bag readiness light should flash for a few
seconds when
you turn the ignition key to RUN. If the
light doesn’t come
on then, have it fixed so it will be
ready to warn
you if there is a problem.
Charging System Indicator Light
The charging system light
will come on briefly when
you turn on the ignition, but
’ the engine is not running,
as a check to show you it
is working.
It should go out once the engine
is running. If it stays
on, or comes on while you are driving, you may have a
problem with the charging system.
It could indicate that
you have problems with
a generator drive belt, or
another electrical problem. Have
it checked right away.
Driving while this light
is on could drain your battery.
If you must drive a short distance with the light on, be
certain to turn off all your accessories, such as the radio
and air conditioner.
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Page 136 of 386

Mode Knob - Automatic Operation
The right knob on the control panel allows you to
choose the direction of air delivery. When the system is
set for automatic operation, sensors will control the air
delivery mode.
Air will come primarily from the floor or
instrument panel outlets, with some air directed to the
windshield to prevent fogging.
When the system is in AUTO mode, the air conditioning
light will turn on, and the recirculation and outside air
lights turn
off. With the system in full auto control
(both the fan and mode knobs
in AUTO), you still have
the ability to override any function. However,
continually overriding the outside air or the
A/C
compressor will limit the ability of the system to cool
the vehicle quickly.
If you push a button for a function which is nor
available, the light next to that button will flash three
times to alert you that it’s not available.
To find your comfort zone, start with the
74°F (23 O C)
setting and allow about 20 minutes for the system to
adjust the temperature if necessary.
With the automatic setting, the
air conditioning compressor
automatically cycles when needed to cool the
air. In cold
weather, when the system senses the need for heat, the
airflow
will be directed out the floor outlets. As the interior temperature approaches the desired setting, the
blower speed will decrease. To maintain interior comfort,
the &ow will adjust between the instrument panel
air
outlets and floor outlets. On bright sunny days in cool
weather, the alrflow may come out
of the air conditioning
and floor outlets (bi-level mode) to maintain comfort and
prevent stuffiiess.
To avoid blowing cold
air in cold weather, the system will
delay turning on the fan until warm
air is available. The
length of delay depends on the outside
air temperature,
engine coolant temperature or the time since the engine was last started.
As the coolant warms up, the blower fan
speed will gradually increase and
air will flow from the
heater outlets, with some airflow to
the windshield to
prevent fogging under most normal conditions.
If your vehicle is sitting out on a warm day and you
have the fan set on AUTO, the air will first flow out of
the floor air outlets
for a few seconds. That is normal.
This is to expel hot air from the air outlets.
As the air is
cooled, the airflow will move through the
air
conditioning outlets.
Be careful not to put anything over the solar sensor
located around the center of the instrument panel.
This sensor is used by the automatic system to
regulate temperature.
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Page 304 of 386

FuseKircuit Usage
Breaker
2
3
4
8
9
10
11
12 Cigarette
Lighter, Data
Link Connector
Cruise Control Module and
Switch, Body Control Module,
Heated Seats
Gages, Body Control Module,
Instrument Panel Cluster
Interior Lights
Not Used
Power Outside Mirror, Power
Lock Relay
Courtesy Lamps, Battery
Run-Down Protection
Not Used
Turn Signal
Cluster, Engine Control Module
Parking Lamps, Power Window
Switch, Body Control Module,
Ashtray Lamp
FuseKircuit
Breaker
13
14
15
16
17
18
19
20
21
22
23
24
Usage
Auxiliary Power
Power Locks Motor
4WD Switch, Engine Controls (VCM, PCM, Transmission)
Air Bag
Front Wiper
Not Used
Radio Battery
Amplifier
HVAC
I (Automatic), HVAC
Sensors (Automatic)
Anti-Lock Brakes
Rear Wiper
Radio, Ignition
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Page 306 of 386

Name
RT TRN
RR PRK
TRL PRK
LT HDLP
RT HDLP
LT HI
RT HI
FR PRK
INT BAT
ENG
I
ECM B
ABS
ECM
1
HORN
BTS
I
BIU LP
IGN E
AIC
RAP
OXYSEN
Usage
Right Turn Signal Rear
Right Rear Parking Lamps
Trailer Park Lamps Left Headlamp
Right Headlamp
Left High Beam
Right High Beam
Front Parking Lamps
I/P Fuse Block Feed
Engine SensorsISolenoids, MAP,
CAM. PURGE, VENT
Engine Control Module, Fuel Pump,
Module, Oil Pressure
Anti-Lock Brake System
Engine Control Module Injectors Horn
Brake-Transmission Shift Interlock
Back-up
Lalllps
Engine
Air Conditioning
Retained Accessory Power
Oxygen Sensor
Name
IGN B
DRL
FOG LP
IGN
A
STUD #2
PARKLP
LR PRK
IGN C
HTDSEAT ATC
RRDFOG
HVAC
TRCHMSL
RR W/W
CRANK
LD LEV
HI BEAM
HAZLP
VECHMSL
HTDMIR
STOPLP
TBC
Usage
Column Feed, IGN 2, 3,4
Daytime Running Lamps
Fog Lamps
Starting and Charging IGN
I
Accessory Feeds, Electric Brake
Parking La~nps
Left Rear Parking Lamps Starter Solenoid, Fuel Pump. PRNDL
Heated Seat
Electronic Transfer Case
Rear Defogger
HVAC System
Trailer Center High Mount Stop Light
Rear Window Wiper
Clutch Switch, NSBU Switch
Electronic Load Leveling
HID Headlamps Hazard Lamps
Vehicle Center High
Mount Stop Lamp
Heated Mirror
Stoplamps
Truck Body Computer
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