Hummer 2007 H3 - Manual (Page 95)

Swing-gate
To lock or unlock the swing-gate, use the power
door lock switch or the remote keyless entry
transmitter.
{ CAUTION:
Make sure the swing-gate is completely
closed. Driving with the swing-gate open
could injure pedestrians or damage the
vehicle.
To open the swing-gate, pull the door handle. Pull
the swing-gate rearward slightly and it will
automatically open.
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