2004 GMC CANYON sensor

When Should an Air Bag Inate?
The driver’s and right front passengers frontal air bags
are designed to deploy only in moderate to severe
frontal, or near-frontal crashes. But they are designed to
inate only if the impact speed is above the system’s
designed “threshold level.”
In addition, your vehicle has “dual stage” frontal air
bags, which adjust the amount of restraint according to
crash severity. For moderate frontal impacts, these
air bags inate at a level less than full deployment.
For more severe frontal impacts, full deployment occurs.
If the front of your vehicle goes straight into a wall
that doesn’t move or deform, the threshold level
for the reduced deployment is about 12 to 16 mph
(19.3 to 26 km/h), and the threshold level for a full
deployment is about 20 to 24 mph (32.2 to 38.5 km/h).
The threshold level can vary, however, with specic
vehicle design, so that it can be somewhat above
or below this range.
If your vehicle strikes something that will move or deform,
such as a parked car, the threshold level will be higher.
The driver’s and right front passenger’s frontal air bags
are not designed to inate in rollovers, rear impacts,
or in many side impacts because ination would not help
the occupant.The side impact air bags are designed to inate in
moderate to severe side crashes. A side impact air bag
will inate if the crash severity is above the system’s
designed “threshold level”. The threshold level can vary
with specic vehicle design. Side impact air bags are
not designed to inate in frontal or near-frontal impacts,
rollovers or rear impacts, because ination would not
help the occupant. A side impact air bag will only deploy
on the side of the vehicle that is struck.
Your vehicle has seat position sensors which enable the
sensing system to monitor the position of the driver’s
seat and the right front passenger’s seat. Seat position
sensors provide information that is used to determine
if the air bags should deploy at a reduced level or at
full deployment.
In any particular crash, no one can say whether an air
bag should have inated simply because of the damage
to a vehicle or because of what the repair costs were.
For frontal air bags, ination is determined by the angle
of the impact and how quickly the vehicle slows down
in frontal or near-frontal impacts. For side impact
air bags, ination is determined by the location and
severity of the impact.
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In many crashes severe enough to inate an air bag,
windshields are broken by vehicle deformation.
Additional windshield breakage may also occur from the
right front passenger air bag.
Air bags are designed to inate only once. After an
air bag inates, you will need some new parts for
your air bag system. If you do not get them, the air
bag system will not 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 electronic frontal
sensors which help the sensing system distinguish
between a moderate and a more severe frontal
impact. If your vehicle has side impact air bags,
it also has electronic side sensors. Your vehicle is
equipped with a crash sensing and diagnostic
module, which records information about the air bag
system. The module records information about
the readiness of the system and when the systemcommands air bag ination. It records the status of
the driver’s safety belt usage in a crash in which
the air bag deploys or a crash in which the air bag
nearly deploys. The module also records speed,
engine rpm, brake and throttle data.
Let only qualied technicians work on your air bag
system. Improper service can mean that your air
bag system will not work properly. See your dealer
for service.
Notice:If you damage the covering for the driver’s
or the right front passenger’s air bag, or the side
impact air bag covering on the ceiling near the side
windows, the bag may not work properly. You may
have to replace the air bag module in the steering
wheel, both the air bag module and the instrument
panel for the right front passenger’s air bag, or
side impact air bag module and ceiling covering
for the roof-mounted side impact air bag. Do not
open or break the air bag coverings.
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Adding Equipment to Your
Air Bag-Equipped Vehicle
Q: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 theCustomer Satisfaction Procedure
on page 7-2.
Restraint System Check
Checking Your Restraint Systems
Now and then, make sure the safety belt reminder light
and all your belts, buckles, latch plates, retractors
and anchorages are working properly. Look for any other
loose or damaged safety belt system parts. If you see
anything that might keep a safety belt system from doing
its job, have it repaired.
Torn or frayed safety belts may not protect you in a
crash. They can rip apart under impact forces. If a belt
is torn or frayed, get a new one right away.
Also look for any opened or broken air bag covers, and
have them repaired or replaced. (The air bag system
does not need regular maintenance.)
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Automatic Headlamp System
Your vehicle may be equipped with this feature.
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 may also
be dim.
Your vehicle may have a light sensor located on the top
of the instrument panel. Be sure it is not covered, or
the system will be on whenever the ignition is on.
The system may also turn on your headlamps when
driving through a parking garage, heavy overcast
weather or a tunnel. 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 system 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.If you start your vehicle in a dark garage, the automatic
headlamp system will come on immediately. Once you
leave the garage, it will take approximately several
seconds for the automatic headlamp system to change
to DRL if it is light outside. During that delay, your
instrument panel cluster may not be as bright as usual.
Make sure your instrument panel brightness control
is in the full bright position. See “Instrument Panel
Brightness” underInterior Lamps on page 3-15.
Lamps On Reminder
If a door is open, a reminder chime will sound when
your headlamps or parking lamps are manually turned
on and your key is out of the ignition. To turn off
the chime, turn the headlamp switch to off and then
back on. In the automatic mode, the headlamps turn off
once the ignition is in LOCK.
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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. Fully functional daytime
running lamps are required on all vehicles rst sold
in Canada.
The DRL system will come on when the following
conditions are met:
The ignition is on.
The exterior lamps control is in AUTO.
The automatic transmission is not in PARK (P).
The light sensor determines it is daytime.
When the DRL are on, only your DRL lamps will be on.
The taillamps, sidemarkers and other lamps will not
be on. The instrument panel will not be lit up either.
When it begins to get dark, the automatic headlamp
system will switch from DRL to the headlamps.
As with any vehicle, you should turn on the regular
headlamp system when you need it.
Fog Lamps
If your vehicle has fog lamps you can use them for
better vision in foggy or misty conditions. Your parking
lamps and/or low-beam headlamps must be on for
your fog lamps to work.
The fog lamp button is
located near the exterior
lamps control.
Press the button to turn the fog lamps on while the
headlamps or parking lamps are on. Press the button
again to turn them off. An indicator light will glow in the
button when the fog lamps are on.
Remember, fog lamps alone will not give off as much
light as your headlamps. Never use your fog lamps
in the dark without turning on the headlamps.
The fog lamps will go off whenever your high-beam
headlamps come on. When the high beams go off,
the fog lamps will come on again.
The fog lamps will be cancelled after the ignition is
turned off. If you still want to use the fog lamps after you
restart the vehicle, you will need to press the fog lamp
button again.
3-14

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 modules, the wiring and the crash sensing and
diagnostic module. For more information on the air bag
systems, seeAir Bag Systems on page 1-60.
This light will come on
when you start your
vehicle, and it will ash
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
vehicle or comes on when you are driving, your air
bag system may not work properly. Have your vehicle
serviced right away.{CAUTION:
If the air bag readiness light stays on after you
start your vehicle, it means the air bag system
may not be working properly. The air bags in
your vehicle may not inate in a crash, or they
could even inate without a crash. To help
avoid injury to yourself or others, have your
vehicle serviced right away if the air bag
readiness light stays on after you start your
vehicle.
The air bag readiness light should ash for a few
seconds when you turn the ignition key to RUN. If the
light doesn’t come on then, have it xed so it will
be ready to warn you if there is a problem.
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Fuse Usage
15 Front Axle Actuator
16Antilock Brake System (ABS),
ABS module, Four-Wheel Drive,
Gravity Sensor
17Supplemental Inatable Restraint
System, Sensing and Diagnostic
Module, Air Bag Off Switch
18 Heated Seat
19Cruise Control Switch, Inside
Rearview Mirror, Transfer Case
Control Module, Brake Switch,
Clutch Disable
20 Electronic Throttle Control (ETC)
21 Power Door Locks
22 Injectors
23Ignition, Clutch Starter Switch,
Neutral Safety Back-Up Switch,
Ignition Coils 1-5, Air Conditioning
Relay
24 Transmission Solenoid
25 Powertrain Control Module (PCM)
26 Back-up Lights
27ERLS, Map Sensor, Can Purge
SolenoidFuse Usage
28 Rear Turn/Hazard Lights
29Driver’s Side RearTaillamp,
Passenger Side Air Bag Indicator
Lighting, Instrument Panel Dimming
Power (2WD/4WD switch lighting)
30 Powertrain Control Module (PCM) B
31 OnStar
32 Radio
33 Auxiliary Power 2
34 Truck Body Controller
35 Horn
36 Transfer Case Control Module
37Turn/Hazard/Courtesy/Cargo Lamps/
Mirrors
38 Cluster
39Rear Parking Lamp 1, Passenger’s
Side Taillamp, License Plate Lamps
40Front Park/Turn Lamps, Driver and
Passenger’s Side Power Window
Switches Lighting
41 Climate Control Fan
42 Power Windows
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Fuse Usage
43 Starter Solenoid Relay
44
Antilock Brake System 2 (ABS Pump)
45Antilock Brake System 1 (ABS Logic)
46Power Seat Circuit Breaker/POA Seat
69 Fuel Canister Vent Solenoid
72 Not Used
73 Not Used
74 Not Used
75 Not Used
77 Air Conditioning Compressor
79 Oxygen Sensors
Relays Usage
47 Beam Selection
50 Air Conditioning Compressor
51 Fuel Pump, Fuel Pump Fuse
52 Fog Lamps
53Front Parking Lamp Fuse, Driver
and Passenger’s Taillamp Fuse,
Rear Parking Lamps
Relays Usage
54Driver and Passenger’s
Headlamps Fuse
55 Horn
56Electronic Throttle Control Fuse,
Oxygen Sensor Fuse
57 Wipers (On/Off)
58Power Window Fuse, Wiper/Washer
Switch Fuse, (Retained Accessory
Power Mode)
59Ignition 3, Climate Control,
Climate Control Head Fuse
61Run/Crank, Air Bag System Fuse,
Cruise Control Fuse, Ignition Fuse,
Back-Up Lamps, ABS Fuse, ERLS,
Front Axle, PCM-1, Injectors Fuse
62 Starter Relay (PCM Relay)
63 Wiper 2 (High/Low)
Miscellaneous Usage
64 Diode — Wiper
65 Diode — Air Conditioning, Clutch
66 Mega Fuse
67 Not Used
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