2004 GMC ENVOY XL brake sensor

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’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.
Your vehicle is equipped with electronic frontal
sensors, which help the sensing system distinguish
between a moderate frontal impact and a more
severe frontal impact. Your vehicle is also equipped
with a crash sensing and diagnostic module,
which records information about the frontal air bag
system. The module records information about
the readiness of the system, when the system
commands air bag ination and driver’s safety belt
usage at deployment. The module also records
speed, engine rpm, brake and throttle data.
Let only qualied technicians work on your air bag
systems. Improper service can mean that an air
bag system won’t 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 air bag
covering on the driver’s and right front passenger’s
seatback, the air 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 both the air bag module and seatback for the
driver’s and right front passenger’s side impact air
bag. Do not open or break the air bag coverings.
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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 about one minute 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.
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,
shift out of park or turn the exterior lamp control to
the off position as described in “Exterior Lamps” listed
previously.
Lamps On Reminder
A reminder tone will sound when your headlamps or
parking lamps are manually turned on, the driver’s door
is open and your ignition is in LOCK or ACCESSORY.
To turn the tone off, turn the knob all the way
counterclockwise. In the automatic mode, the headlamps
turn off once the ignition key is in LOCK.
Daytime Running Lamps (DRL)
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 make your headlamps come on
at reduced brightness when the following conditions
are met:
The ignition is on
the exterior lamps knob is in automatic
headlamp mode
the light sensor detects daytime light
the transmission is not in PARK (P)
When the DRL are on, only your headlamps will be on.
The taillamps, sidemarker and other lamps won’t be
on. The instrument panel won’t be lit up either.
When it begins to get dark, the headlamps will
automatically switch from DRL to the regular headlamps.
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Fuses Usage
29 Oxygen Sensor
30 Air Conditioning
31 Truck Body Controller
32 Trailer
33 Anti-Lock Brakes (ABS)
34 Ignition A
35 Blower Motor
36 Ignition B
50 Passenger’s Side Trailer Turn
51 Driver’s Side Trailer Turn
52 Hazard Flashers
53 Electric Adjustable Pedal
54 A.I.R. Solenoid
56 A.I.R. PumpRelays Usage
37 Headlamp Washer
38 Rear Window Washer
39 Fog Lamps
40 Horn
41 Fuel Pump
42 Windshield Washer
43 High-Beam Headlamp
44 Air Conditioning
45 Cooling Fan
46 Headlamp Driver Module
47 Starter
49 Electric Adjustable Pedal
55 A.I.R. Solenoid
Miscellaneous Usage
48 Instrument Panel Battery
49 Blank
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Fuses Usage
30 Air Conditioning
31 Truck Body Controller 1
32 Trailer
33 Anti-Lock Brakes (ABS)
34 Ignition A
35 Blower Motor
36 Ignition B
50 Passenger’s Side Trailer Turn
51 Driver’s Side Trailer Turn
52 Hazard Flashers
53 Oxygen Sensor Bank B
54 Oxygen Sensor Bank A
55 Injector Bank A
56 Injector Bank B
57 Electric Adjustable PedalRelays Usage
37 Headlamp Washer
38 Rear Window Washer
39 Fog Lamps
40 Horn
41 Fuel Pump
42 Windshield Washer
43 High-Beam Headlamp
44 Air Conditioning
45 Cooling Fan
46 Headlamp Driver Module
47 Starter
49 Electric Adjustable Pedal
58 Ignition 1
Miscellaneous Usage
48 Instrument Panel Battery
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