1997 GMC SAVANA sensor

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 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.
What will you see after an air bag inflates?
After an air bag inflates, it quickly deflates, so quickly
that some people may not even realize the air bag
inflated. Some components of the air bag module
-- in
the steering wheel hub for the driver’s air bag
-- or the
instrument panel for the right front passenger’s bag,
will be hot for a short time. The parts
of the bag that
come into contact with you may be warm, but not
too
hot to touch. There will be some smoke and dust coming
from vents in the deflated air bags. Air bag inflation
doesn’t prevent the driver from seeing or from being
able to steer the vehicle, nor does it stop people from
leaving the vehicle.
I
A CAUTION:
When an air bag inflates, there is dust in the air.
This dust could cause breathing problems
for
people with a history of asthma or other
breathing trouble.
To avoid this, everyone in the
vehicle should get out as soon as it
is safe to do so.
If you have breathing problems but can’t get out
of the vehicle after an air bag inflates, then get
fresh air by opening a window or door.
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 system
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.
0 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, when the sensors are
activated and driver’s safety belt usage at deployment.
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Adding Equipment to Your Air
Bag-Equipped Vehicle
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.
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 Satisfaction Procedure in this
manual.
See “Customer Satisfaction Procedure” in the Index.)
Rear Seat Passengers
It’s very important for rear seat passengers to buckle up!
Accident statistics show that unbelted people in the rear
seat
are hurt more often in crashes than those who are
wearing safety belts.
Rear passengers who aren’t safety belted can be thrown
out
of the vehicle in a crash. And they can strike others
in the vehicle who are wearing safety belts.
Rear Seat Outside Passenger Positions
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Air Bag Readiness Light
There is an air bag readiness light on the instrument
panel, which shows
AIR BAG. 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, see “Air
Bag” in the Index.
AIR
BAG
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 Light
This light should come on
briefly when you turn
on the
ignition, before starting the
engine, as a check to show
you it is working.
After the engine starts, the light should go out. If
it stays
on or comes on while you are driving, you may have a
problem with your charging system. It could indicate a
problem with the alternator
drive belt, or some other
charging system problem. Have it checked right away.
Driving while this light is on could drain your battery.
If you must drive a short distance with this light on, it
helps to turn off all your accessories, such as the radio
and air conditioner.
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Voltmeter
When your engine is not
running, but the ignition is
on (in the RUN position),
this gage shows your
battery’s state of charge in
DC volts.
When the engine is running, the gage shows the
condition
of the charging system. Readings between the
low and high warning zones indicate the normal
operating range. Readings
in the
low warning zone may occur when a
large number of electrical accessories are operating in
the vehicle and the engine is left at an idle for an
extended period. This condition is normal since the
charging system
is not able to provide full power at
engine idle.
As engine speeds are increased, this
condition should correct itself as higher engine speeds
allow the charging system to create maximum power.
You can only drive for a short time with the reading in
either warning zone. If you must drive, turn
off all
unnecessary accessories.
Readings in either warning zone indicate a possible
problem in the electrical system. Have the vehicle
serviced as soon as possible.
Electronic Road-Speed Governor
(Gasoline Engines) (Option)
This optional system automatically controls vehicle top
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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Engine Compartment Fuse Relay Center
The fuse block is on the driver's side of the engine
compartment at the rear.
[-I
[)
[T]
Name
BLOWER
ABS
Circuits Protected
Blower Motor
Electronic Brake Control Module
Name
IGN-B
IGN-A
BATT
LIGHTING
RR BLOWER
ENG-
1
A/C SPARE
AUX A
AUX-B
RH-HDLP
Circuits Protected
Ignition Switch
Starter Relay, Ignition Switch
Instrument Panel Fuse Block
Instrument Panel Fuse Block,
Headlamp Switch
Rear Auxiliary Blower
Motor Relays
Heated
02 Sensors, Mass Air
Flow Sensor, EGR Valve
Solenoid, Evap Canister Purge
Valve, Crankshaft Position Sensor,
Secondary Air Injection Relay
(Diesel), Water in Fuel Sensor
(Diesel), Fuel Heater (Diesel),
Glowplug Relay (Diesel),
Wastegate Solenoid (Diesel)
Air Conditioning Clutch Relay
Spare Fuses
Upfitter Provisions
Upfitter Provisions
Right-hand Headlamp
(Export Only)
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Name
RH-HIBM
ECM-I
HORN
LH-HDLP
LH-HIBM
FUEL SOL
IGN-E
ECM-B
Circuits Protected
Right-hand High-beam Headlamp
(Export Only)
Ignition Coil, Crankshaft Position Sensor, VCM, Fuel Injectors,
Coil Driver
Horn Relay, Underhood Lamp(
s)
Left-hand Headlamp
(Export Only)
Left-hand High-beam Headlamp
(Export Only)
PCM, Fuel Solenoid Driver,
Engine Shutoff Solenoid
Air Conditioning Clutch Relay
Fuel Pump Relay, VCM, PCM,
Fuel Pump and Engine Oil
Pressure Switch
Capacities and Specifications
Replacement Parts
Replacement part numbers listed in this section are
based on the latest information available at the time of
printing, and are subject to change. If a part listed in this
manual is not the same as the part used in your vehicle
when
it was built, or if you have any questions, please
contact your GM truck dealer.
These specifications
are for information only. If you
have
any questions, see the service manual for the
chassis or refer to the body manufacturer’s publications.
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