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RADAR CRUISE NOT READY
When this message displays, it means that the Adaptive
Cruise Control system will not activate due to a
temporary condition. Your vehicle does not require
service. This message will also display when either of
the following conditions occurs:
The driver turns off the head-up display (HUD)
while the Adaptive Cruise Control is engaged.
The driver attempts to engage the Adaptive Cruise
Control while the HUD is off.
If this message appears when you attempt to activate
the system, continue driving for several minutes
and then try activating the system again.
RIGHT REAR DOOR AJAR
This symbol appears with
the RIGHT REAR DOOR
AJAR message.
When this message displays, it means that the
passenger’s side rear door was not closed completely.
You should check to make sure that the door is
closed completely.
SERVICE AC (Air Conditioning)
SYSTEM
This message will display when the electronic sensors
that control the air conditioning and heating systems are
no longer working. Have the climate control system
serviced by your GM dealer if you notice a drop
in heating and air conditioning efficiency.
SERVICE AIR BAG
This message will display when there is a problem with
the airbag system. Have your vehicle serviced by
your GM dealer immediately. SeeAirbag Readiness
Light on page 3-60for more information.
SERVICE BRAKE ASSIST
This message will display when a problem with the
panic brake assist system has been detected. Have your
vehicle serviced by your GM dealer.
SERVICE RADAR CRUISE
When this message displays, it means that the Adaptive
Cruise Control system is disabled and needs service.
See your GM dealer.
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Driving on Grades
Reduce speed and shift to a lower gearbeforeyou start
down a long or steep downgrade. If you do not shift
down, you might have to use your brakes so much that
they would get hot and no longer work well.
Climbing grades steeper than four percent at
temperatures above 90° F (32° C) with a loaded vehicle
and trailer is not recommended. The cooling system
may temporarily overheat. SeeEngine Overheating on
page 5-30.
Parking on Hills
{CAUTION:
You really should not park your vehicle, with a
trailer attached, on a hill. If something goes
wrong, your rig could start to move. People
can be injured, and both your vehicle and the
trailer can be damaged.
But if you ever have to park your rig on a hill, here is
how to do it:
1. Apply your regular brakes, but do not shift into
PARK (P). When parking uphill, turn the wheels
away from the curb. When parking downhill, turn
the wheels into the curb.
2. Have someone place chocks behind the
trailer wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then shift into
PARK (P) rmly and apply your parking brake.
5. Release the regular brakes.
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When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
start your engine
shift into a gear, and
release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store
the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you are
pulling a trailer. See the Maintenance Schedule for
more on this. Things that are especially important in
trailer operation are automatic transmission uid (do not
over ll), engine oil, drive belt, cooling system and
brake system. Each of these is covered in this manual,
and the Index will help you nd them quickly. If you
are trailering, it is a good idea to review this information
before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Engine Cooling When Trailer Towing
Your cooling system may temporarily overheat during
severe operating conditions. SeeEngine Overheating on
page 5-30.
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