sensor CHEVROLET EXPRESS 2003 Owners Manual

If the GVWR (Gross Vehicle Weight Rating) of your
vehicle is 8,500 lb (3 855 kg) or above, your vehicle has
single stage airbags. If the GVWR is below 8,500 lb
(3 855 kg) then your vehicle has dual stage airbags. You
can nd the GVWR on the certication label on the
rear edge of the driver’s door. SeeLoading Your Vehicle
on page 4-29for more information.
Single Stage Airbags
If your vehicle has frontal airbags with single stage
deployment and your vehicle goes straight into a wall
that does not move or deform, the threshold level
is about 9 to 16 mph (14 to 26 km/h). (The threshold
level can vary, however, with specic vehicle design, so
that it can be somewhat above or below this range.)
Dual Stage Airbags
If your vehicle has frontal airbags with dual stage
deployment, the restraint will adjust according to the
crash severity. Your vehicle is equipped with electronic
frontal sensors which help the sensing system
distinguish between a moderate and a more severe
frontal impact. For moderate frontal impacts, these
airbags 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
does not move or deform, the threshold level for the
reduced deployment is about 12 to 16 mph
(19 to 26 km/h), and the threshold level for a full
deployment is about 16 to 25 mph (26 to 40 km/h).
(The threshold level can vary, however, with specic
vehicle design, so that it can be somewhat above
or below this range.)
Vehicles with dual stage airbags 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 airbags
should deploy at a reduced level or at full deployment.
What Makes an Airbag Inate?
In an impact of sufficient severity, the airbag sensing
system detects that the vehicle is in a crash. The
sensing system triggers a release of gas from the
inator, which inates the airbag. The inator, airbag,
and related hardware are all part of the airbag modules
inside the steering wheel and in the instrument panel
in front of the right front passenger.
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Adding Equipment to Your
Airbag-Equipped Vehicle
Q:Is there anything I might add to the front of the
vehicle that could keep the airbags 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 airbag system from
working properly. Also, the airbag system may not
work properly if you relocate any of the airbag
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 airbag covers, and
have them repaired or replaced. (The airbag system
does not need regular maintenance.)
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Speedometer and Odometer
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).
Your vehicle has a tamper resistant odometer. The
digital odometer will read 999,999 if someone tries to
turn it back.
You may wonder what happens if your vehicle needs a
new odometer installed. If the new one 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.
Press the reset button, located on the instrument panel
cluster next to the trip odometer display, to toggle
between the trip odometer and the regular odometer.
Holding the reset button for approximately one second
while the trip odometer is displayed will reset it.
To display the odometer reading with the ignition off,
press the reset button.
Engine Speed Limiter
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 chime will
be provided for several seconds to remind people to
buckle their safety belts. The driver safety belt light will
also be provided and stay on for several seconds,
then it will ash for several more. You should buckle
your seat belt.
This chime and light will be
repeated if the driver
remains unbuckled and the
vehicle is in motion.
If the driver’s belt is buckled, neither the chime nor the
light will be provided.
Airbag Readiness Light
There is an airbag readiness light on the instrument
panel, which shows the airbag symbol. The system
checks the airbag’s electrical system for malfunctions.
The light tells you if there is an electrical problem.
The system check includes the airbag sensor, the airbag
modules, the wiring and the crash sensing and
diagnostic module. For more information on the airbag
system, seeAirbag System on page 1-59.
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.
3-25

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 Blower
52 Ignition B
63 Spare
64 SpareFuse Usage
Relays 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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