On my 2006 tahoe the rear hatch wont open and neither will the window using the unlock buttons on the hatch you can hear it working but not enough to actually release the door. Also i have noticed that the brake light on the rear hatch does not work and the license plate lights will dimmly come on when you push the release buttons. I know that its not a fuse problem and like i said earlier you can hear the actuator working just doesn't turn enough to allow the door to open

SOURCE: rear hatch window will not release

http://blazerforum.com/forum/showthread.php?t=12396
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SOURCE: 99Century My license plate and backup lights don't work

remove the light pannel and check the sockets for corrosion and the trunk release should be in the glove box

SOURCE: changing license plate lights on 2004 chevrolet

the light can be replaced from the back side of the light housing . go under the back side of bumper under the truck behind lisence plate you will see the where the wire goes to the light . grab the housing not the wires and twist about a half a turn and pull gently. it should come out and then remove the light bulb and replace with new

SOURCE: Where is the fuse for the license plate bulbs of a

the headlamp switch controls the license light. the filament in all bulbs react as a fuse when shorted out. replace the bulb

SOURCE: How can I change the rear license plate lights on

there are clips on the side of the bulb holders that squeeze together then push out to reveal the bulb holder. you can locate these by opening the boot lid, and on most mosels removing the plastic surround. you can then see the holders inside. just hold finger and thumb at each end and gently squeeze the clips and push out the holder to replace buls