Doorking manual model 805

Question edited for clarity and typos.
Question moved to model category.

Others report the same issue.

https://www.google.com/search?q=2009+Tahoe.+The+rear+lift+gate+open+on+its+own

The latching delay is an important safety feature on an Elite gate opener, and it is not recommended to defeat it. The purpose of the delay is to ensure that the gate is fully closed and in the correct position before the magnet engages to latch the gate. Disabling the delay could cause the gate to not close properly, which could be a safety hazard and may also damage the gate and the gate opener.
If the magnet is not grabbing the gate on the first impact, there could be several reasons for this. One possible cause is that the magnet is not properly positioned, which could cause it to miss the gate on the first impact. In this case, adjusting the magnet's position may help.
Another possible cause is that the gate is not aligned properly, which could prevent the magnet from making contact with the gate on the first impact. In this case, adjusting the gate's alignment may help.
It is recommended to refer to the owner's manual for your Elite gate opener to learn more about the proper position and alignment of the magnet and the gate.

Tailgate? Farm Gate? Automatic sliding gate?

Year make model
in all vehicle questions.

make model (what it is)
in all others please. We need those details to solve!

most sliding gates suffer form dirt, grass , rocks in the gate track so constant cleaning of that track is essential
small twigs , rocks will slide along with the wheels on opening but are an obstruction for the wheels on closing
most closing gates run a cog and rack system at the bottom ot the gate so check that the mesh of the rack and cog is correct at either end

Open the tail gate and unbolt the gate end and slide top off retaining bolt.

Check it out on you tube !

Your manual override is active. This disengages the gearbox from running the gate. You will need to release the manual override. What make and model gate motor is it?

I would suggest an owners manual

If you own a vehicle,why would you not want one

Helm.com

Have to order & buy it

Dealer will give you the same site

I have this problem with one of my locks. I have been told that it is the actuator.

The easy part is you just need the latch for the liftgate. The hard part is getting to it and opening the liftgate to replace the latch. You should be able to pull the liftgate trim off most of the way with the gate closed and try to manually actuate the latch to open the gate. You may have to go so far as breaking the latch from the inside to open the gate and then replace your latch.