2008 Convertible Automatic. Parked overnight in my garage with the top down. Started to take it out this evening and attempted to put the top up. Pushed the button and the Hatch opened and the top started to come out. When the top was partially out the hatch started to close as normal but wouldn't latch which wouldn't allow the top to completely finish going up. Pushed the down button and the hatch opened as normal and the top folded back into it's compartment but when the hatch came back down it wouldn't latch again and the motor to continue to run. Tried several fixes including raising the driver side window 3X but no effect. Top would go partially up but hatch wouldn't latch. Top would go down but again hatch wouldn't latch and the motor kept running. So not to run down the battery I disconnected it. Let it sit for awhile then reconnected it. Still the same problem. Finally I opened the hatch manually using the cable and raised the hatch by hand. When it lowered from loosing pressure I finally got it to latch but now the button controlling the up and down won't function.
Any Ideas???

 

You will need a Tech 2 to check for codes on the BCM, is anything at all in the floorboard wet? I would suspect the BCM but need to be for sure. There are some switches back on the decklid that can cause issues but that is why you need to check the codes. Does is say anything on the dash about the decklid or trunk either in the open or closed position?

 

It sounds likely that the hatch pulldown motor broke. It's a common issue on a cheaply designed, mostly plastic piece.

 

Nothing wet on the floor. the car sleeps in an enclosed garage. Only thing on the DIC says is Top Not Secure. I'm taking it to the dealership this morning to get it diagnosed.

 

Problem diagnosed. Bad "Folding Top Module"
Ordered new unit. Good news is it's readily available. Bad news is dealership couldn't tell me exactly when it would be in. May be 4 days or 4 months. With the strike currently in effect no promises could be given. So for now the top is up and my car can be driven, just can't operate the top up and down until the new unit comes in.

 

When you disconnect the battery you then need to reindex the windows otherwise the top won't work. So reindex the windows first. Now I had an identical problem you are describing and it was the pull down motor inside the waterfall. It has plastic gears which break over time and then won't pull down the tonneau so the top won't go up.
Don't get sucked into a new expensive MODULE. The part (motor with gears ) is this part

GM Genuine Parts 25809368 Trunk Lid Pull Down Motor

and costs about $250 and takes about 1 hour to install. I think that's probably your issue.

 

that's exactly the issue and the part is on order. thanks for the information

 

Hmmmmm.............