GMC Chevrolet Tahoe 2003 Manual page 110

Liftgate
{
CAUTION:
It Can be dangerous to drive with the liftgate
glass, liftgate or rear doors open because
carbon monoxide (CO) gas can come into your
vehicle. You can't see or smell CO. It can
cause unconsciousness and even death.
If you must drive with the liftgate glass, liftgate
or rear doors open or if electrical wiring or
other cable connections must pass through
the seal between the body and the liftgate
glass, liftgate or rear doors:
•
Make sure all other windows are shut.
•
Turn the fan on your heating or cooling
system to its highest speed with the
setting on VENT or OUTSIDE AIR. That will
force outside air into your vehicle. See
"Climate Control System" in the Index.
•
If you have air outlets on or under the
instrument panel, open them all the way.
See "Engine Exhaust" in the Index.
2-14
Liftgate Glass and Liftgate
To open a mechanical lock system from the outside,
insert the key into the lock and turn it counterclockwise
to unlock the glass and liftgate.
The liftgate glass can be opened using the button on
the liftgate after the doors have been unlocked. This can
be done by using either the power door locks or the
remote keyless entry system.
To open the entire liftgate, lift the handle located in the
center of the door.
To lock a power lock system from the outside, insert the
key into the lock button and turn clockwise. All doors will
lock. You may also use the keyless entry system or the
power door locks to lock the liftgate and liftgate glass.