09 Yukon Rear hatch won't fully open

[Chev454ss]

My rear hatch unlatches and starts to open. It opens about 16" or so, then it closes on its own. I tried forcing it the rest of the way, but when I do that it still closes on its own. I've shut it off and turned it back on, used the clicker and switch in the truck, same result. Where do I go from here?

 

[swathdiver]

@Doubeleive

 

[Doubeleive]

My rear hatch unlatches and starts to open. It opens about 16" or so, then it closes on its own. I tried forcing it the rest of the way, but when I do that it still closes on its own. I've shut it off and turned it back on, used the clicker and switch in the truck, same result. Where do I go from here?

hard to say from your description but it could be the gas strut is tired and is not "assisting" with opening the hatch.
if it opens with a little help from a couple fingers it could be just the strut
the hatch should stay up and open if you lift it manually, if it does not stay up and open on it's own without help then that is likely the strut as well
additionally if you open it manually after about 1/2 way or so it should go up on it's own with just the gas strut power

 

[Chev454ss]

I don't know how I could have been much clearer. When I physically assist while the door is trying to open, I force it into the open position. Once it's fully open it closes unprompted. Is there an encoder on the motor that could be out of sync? The liftgate takes force to open, it's as if it's fighting to close.

 

[OR VietVet]

I recently fixed a similar problem on a 2018 Suburban for my girl's landlord. Turned out it was the left strut/motor arm for the rear liftgate. I know yours has a different liftgate motor set up but if I was you, I would lean toward the motor starting to fail or the signal at the latch assembly getting lost.

 

[intheburbs]

The tailgate is heavy.
The electric tailgate also will reverse if it senses an obstacle.
If the gas struts that assist raising the tailgate go bad, the additional force needed causes the tailgate to behave as if it hit an obstacle and reverses.
Ditto the tailgate not staying open.
Replace the gas struts and the problem will be fixed.

Order the struts for the glass while you're at it. They're cheap. Here's my order from last year - $60 for all four struts from Rock Auto. Stabilus brand - the top name.

 

[Doubeleive]

I don't know how I could have been much clearer. When I physically assist while the door is trying to open, I force it into the open position. Once it's fully open it closes unprompted. Is there an encoder on the motor that could be out of sync?

it's not a encoder.....
I gave details of what it "could" be
that being said, if it will not stay open on it's own, with the front rooftop switch turned off (manual only mode) then the struts are bad.

 

[Chev454ss]

I just tried opening it in manual, and it looks like it may be the struts as you said. It fights me all the way and won't stay open. Thanks!

 

[Doubeleive]

I just tried opening it in manual, and it looks like it may be the struts as you said. It fights me all the way and won't stay open. Thanks!

EASY FIX, the struts can be changed out in seconds, there is a little C clip on each end, pull that clip up and the ball end will come right off. I would replace both sides at the same time. you can do it yourself but it's helpful to have a helper hold the hatch up while you change out the struts.

 

[Geotrash]

I've had mixed results with struts from the local Advanced Auto. Best to buy from rockauto.com and get a quality brand.