2004 CHEVROLET EXPRESS CARGO VAN sensor

Seat Position Sensors
Vehicles with dual stage air bags are also equipped with
special sensors which enable the sensing system to
monitor the position of both the driver and passenger
front seats. The seat position sensors provide
information which is used to determine if the air bags
should deploy at a reduced level or at full depoyment.
Air Bag Systems
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.
Ination is determined by the angle of the impact
and how quickly the vehicle slows down in front or
near-frontal impacts.
What Makes an Air Bag Inate?
In an impact of sufficient severity, the air bag sensing
system detects that the vehicle is in a crash. The
sensing system triggers a release of gas from the
inator, which inates the air bag. The inator, air bag,
and related hardware are all part of the air bag
modules inside the steering wheel and in the instrument
panel in front of the right front passenger.
How Does an Air Bag Restrain?
In moderate to severe frontal or near-frontal collisions,
even belted occupants can contact the steering wheel or
the instrument panel. Air bags supplement the
protection provided by safety belts. Air bags distribute
the force of the impact more evenly over the occupant’s
upper body, stopping the occupant more gradually.
But air bags would not help you in many types of
collisions, including rollovers, rear impacts and many
side impacts, primarily because an occupant’s motion is
not toward those air bags. Air bags should never be
regarded as anything more than a supplement to safety
belts, and then only in moderate to severe frontal or
near-frontal collisions.
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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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Speedometer
Your speedometer lets you see your speed in both
miles per hour (mph) and kilometers per hour (km/h).
Your odometer shows how far your vehicle has
been driven, in either miles (used in the United States)
or kilometers (used in Canada).
You may wonder what happens if your vehicle needs a
new odometer installed. Laws vary as to the procedure
that must be followed, so check with your state or
provincial vehicle registration office. But generally, if the
new odometer can be set to the mileage total of the
old odometer, then it must be. But if it can’t, then it’s set
at zero, and a label must be put on the driver’s door
to show the old mileage reading when the new odometer
was installed.
Trip Odometer
The trip odometer can tell
you how far your vehicle
has been driven since
you last set the trip
odometer to zero.
To reset the trip odometer, fully press the reset button
located near the trip odometer readout.
The trip odometer can show either total miles or trip
miles using this button located on the instrument cluster.
Electronic Road-Speed Governor
Your vehicle may have this feature. This system
automatically controls top vehicle speed. The system
controller receives a signal from the vehicle speed sensor
and reduces power when the vehicle speed reaches the
maximum 65 mph (105 km/h) governed speed.
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Safety Belt Reminder Light
When the key is turned to RUN or START, a tone will
come on for several seconds to remind people to fasten
their safety belts, unless the driver’s safety belt is
already buckled.
The safety belt light will
also come on and stay on
for several seconds, then it
will ash for several more.
If the driver’s belt is already buckled, neither the tone
nor the light will come on.
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 sensor, the air
bag modules, the wiring and the crash sensing and
diagnostic module. For more information on the air bag
system, seeAir Bag System on page 1-70.
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.
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Fuse Usage
38 Powertrain Control Module Ignition 1
39 Oxygen Sensor B
40 Oxygen Sensor A
41 Windshield Wipers
42 Right Headlamp — Low Beam
43 Left Headlamp — Low Beam
44 Left Headlamp — High Beam
45 Right Headlamp — High Beam
46Truck Body Control
Module-Accessory
47 Front Windshield Wiper
48 Anti-Lock Brakes
49 Ignition A
50 Trailer
51 Climate Control BlowerFuse Usage
52 Ignition B
63 Spare
64 Spare
Relay Usage
53 Windshield Wiper
54 Air Conditioning
55 Spare
56 Headlamp —High Beam
57 Fuel Pump
58 Headlamp — Low Beam
59 Horn
61 Starter
62 Spare
Circuit Breaker Usage
60 Power Seat
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