Hatch won't close

There are small gas charged shocks that hold open the hatch, you need to replace them as there is no repairing them.

Check and adjust the sensor at the latch or in the lock

You have a SHORT, check for chafing of the wires...

Look at your maintenance manual. To find where your fuse box is located(may be under the hood or under the steering wheel). When you find the fuse box look on the back of the panel flap and you'll find a fuse map. Locate the fuse that corresponds with your problem. It could be the same fuse but not likely. If fuse is blown then replace it with a spare. Most manufacturers will put spare fuses in the box or you could pull a fuse from some where else just to try and see if the problem is still there( make sure it's the same size and understand that it could blow this fuse as well then you will need 2 fuses). Most of the time fuses don't just blow. For some reason it pulled to much load. Probably a dead short in the wiring. I hope this helps.

If the motor requires too much voltage to finish the cycle, it could trigger the computer to think there is a blockage.

Go into the rear hatch cargo area and remove the trim panel over the latch and trip it manually. I know this works have done it myself on my 1996

while cleaning the car did you trip the valet switch shutting it off?

It sounds like the lock actuator has failed or has a poor connection which won't allow the latch to release. What you will need to do is remove the inside rear hatch panel to access the lock actuator. Once you get to the latch use a flat screwdriver to release the latch being careful not to damage the glass.

----------- Click this link below for more troubleshooting:-- http://technoanswers.blogspot.com/2011/09/rear-hatch-wont-open-on-2005-gmc-yukon.html -------- This will help.Thanks.Helpmech.

Did you remove the safety clip that stops it from collapsing during installation? Some of these need to be installed compressed and if they extend too far out they will lock up. I would remove the support, compress it at least halfway and then put it back in place with the hatch halfway closed if possible. Then lift the gate and see if that helps in the operation. This assumes you are talking about the spring tension Hydraulic lift bar on the hatch and that you can reach the connecting points with the hatch partially closed.

The switch on the latch is more then likely stuck. If you can see it spray it with some electrical cleaner and open and shut the hatch a few times.