2004 GMC ENVOY XL clock

Electronically Controlled Air
Suspension System
Your vehicle may be equipped with an electronically
controlled air suspension system that automatically
keeps your vehicle level as you load and unload. The
system includes a compressor, two height sensors
and two air springs supporting the rear axle.
The system also has an internal clock to prevent
overheating. If the system overheats, all leveling function
stops until the system cools down. During this time,
the indicator light on the air inator system will be
ashing.
The ignition has to be on for the system to inate, in
order to raise the vehicle to the standard ride height
after loading. The system can lower the vehicle to the
standard ride height after unloading with the ignition
on and also for up to 30 minutes after the ignition has
been turned off.
You may hear the compressor operating when you load
your vehicle, and periodically as the system adjusts
the vehicle to the standard ride height.Load leveling will not function normally with the inator
hose attached to the inator outlet. Remove the inator
hose from the outlet during loading and unloading.
If the vehicle is parked for an extended period of time,
some bleed down of the suspension is normal. Upon
starting the vehicle, proper height will be achieved.
Overload Protection
The air suspension system is equipped with overload
protection. Overload protection is designed to protect
the air suspension system, and it is an indicator
to the driver that the vehicle is overloaded. When the
overload protection mode is on, it will not allow damage
to the air compressor. However, do not overload the
vehicle. SeeLoading Your Vehicle on page 4-49.
If the suspension remains at a low height, the rear
axle load has exceeded GAWR (Gross Axle Weight
Rating). When the overload protection mode is activated,
the compressor operates for about 30 seconds to one
minute without raising the vehicle depending on the
amount of overload. This will continue each time
the ignition is turned on until the rear axle load is
reduced below GAWR.
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While refueling, hang the fuel cap by the tether using
the hook located on the inside of the ller door.
To remove the fuel cap, turn it slowly to the left
(counterclockwise).
{CAUTION:
If you spill fuel and then something ignites it,
you could be badly burned. Fuel can spray out
on you if you open the fuel cap too quickly. This
spray can happen if your tank is nearly full, and
is more likely in hot weather. Open the fuel cap
slowly and wait for any “hiss” noise to stop.
Then unscrew the cap all the way.
Be careful not to spill fuel. Don’t top off or overll your
tank, and wait a few seconds after you’ve nished
pumping before you remove the nozzle. Clean fuel
from painted surfaces as soon as possible. See
Cleaning the Outside of Your Vehicle on page 5-91.
When you put the fuel cap back on, turn it to the
right (clockwise) until you hear a clicking sound.
Make sure you fully install the cap. The diagnostic
system can determine if the fuel cap has been left
off or improperly installed. This would allow fuel
to evaporate into the atmosphere. SeeMalfunction
Indicator Lamp on page 3-43.
5-8

How to Add Coolant to the Radiator
1. You can remove the radiator pressure cap when
the cooling system, including the radiator pressure
cap and upper radiator hose, is no longer hot.
Turn the pressure cap slowly counterclockwise
about one full turn.
If you hear a hiss, wait for that to stop. A hiss
means there is still some pressure left.2. Then keep turning the pressure cap. Remove the
pressure cap.
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Bulb Replacement
For the type of bulbs, seeReplacement Bulbs on
page 5-53.
For any bulb changing procedure not listed in this
section, contact your dealer.
Halogen Bulbs
{CAUTION:
Halogen bulbs have pressurized gas inside
and can burst if you drop or scratch the bulb.
You or others could be injured. Be sure to
read and follow the instructions on the bulb
package.
Headlamps
1. Open the hood.
2. Lift the inner quick release clips.
3. Pull the headlamp assembly away from the vehicle.
4. Remove the cover from the headlamp bulb.
5. Disconnect the wiring harness.
6. Remove the headlamp bulb by turning the socket
counterclockwise.
7. To install the replacement bulb, reverse Steps 1
through 6.
Front Turn Signal and Sidemarker
Lamps
Follow the same procedure listed for headlamp removal
earlier in this section. Replace the turn signal or
sidemarker bulb instead.
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To use the air inator, attach the appropriate nozzle
adapter to the end of the hose if required. Then attach
that end of the hose to the object you wish to inate.
Attach the other end of the hose to the outlet.
Press and release the switch to turn the air inator on.
The indicator light will remain on when the inator is
running.
The system has an internal clock to prevent overheating.
The system will allow about ve minutes of running
time, then the compressor will stop. The indicator light
will then begin to ash. When the indicator is off,
the inator can be started again by pressing the switch.
If the compressor is still hot, it may only run for a
short time before shutting off again.
Press and release the switch to turn the inator off.
Place the inator kit tools in the pouch and store
it properly. Remove the inator hose from the outlet
during loading and unloading. Load leveling will
not function with the inator hose attached to the inator
outlet. See “Electronically Controlled Air Suspension
System” underLoading Your Vehicle on page 4-49
for more information.To reinstall the cover, line up the tabs at the back of the
cover, put it in place and latch the tabs.
A continuous ashing indicator light may also indicate
a malfunction in the air suspension system. See
“Electronically Controlled Air Suspension System” under
Loading Your Vehicle on page 4-49for more information.
{CAUTION:
Inating something too much can make it
explode, and you or others could be injured.
Be sure to read the inator instructions, and
inate any object only to its recommended
pressure.
5-72

Removing the Spare Tire and Tools
The jacking equipment you will need is stored under the
rear seat in the Envoy or in the left rear quarter panel
storage compartment in the Envoy XL. To release
the jack from its holder, turn the knob on the jack
counterclockwise to lower the jack head. SeeRear Seat
Operation on page 1-5 Envoy
Envoy XL
5-75

2. Turn the wheel wrench counterclockwise to lower
the spare tire. Keep turning the wheel wrench until
the spare tire can be pulled out from under the
vehicle.
If the spare tire does not lower to the ground, the
secondary latch is engaged causing the tire not to
lower. See “Secondary Latch System” later in this
section.
When the tire has been completely lowered, tilt the
retainer at the end of the cable and pull it through
the wheel opening. Pull the tire out from under
the vehicle.
Notice:If you drive away before the spare tire or
secondary latch system cable has been reinstalled,
you could damage your vehicle. Always reinstall
this cable before driving your vehicle.3. Put the spare tire near the at tire.
4. Position the chisel end of your wheel wrench in the
notch of the center cap and pry off the center cap.
See “Removing the Flat Tire and Installing the Spare
Tire” later in this section to continue changing the
at tire.
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2. If it is not visible, proceed to Step 6.
If visible, rst try to tighten the cable by turning the
wheel wrench clockwise until you hear two clicks
or feel it skip twice. You cannot overtighten
the cable.
3. Loosen the cable by turning the wheel wrench
counterclockwise three or four turns.
4. Repeat this procedure at least two times.
If the spare tire lowers to the ground, continue with
Step 2 of “Removing the Spare Tire and Tools”
earlier in this section.
5. Turn the wrench counterclockwise until
approximately 6 inches (15 cm) of cable is exposed.
6. Attach the jack handle, extension and the wheel
wrench to the jack and place it under the vehicle
towards the front of the rear bumper. Position
the center lift point of the jack under the center
of the spare tire.
7. Turn the wrench clockwise to raise the jack until it
lifts the end tting.
8. Continue raising the jack until the spare tire stops
moving upward and is held rmly in place. The
secondary latch has released and the spare tire is
balancing on the jack.
5-79