Truck not auto-locking reliably?

todd308 · June 11, 2021

My 20' did this without fail for a year, so when you would walk away from it, it would automatically lock the doors.

My 21' however appears to only do this sometimes, other times it never locks the doors at all. I've doubled checked the setting, tried resetting it. Still does it. I'd say 1 out of 5 times it won't lock.

Anyone else run into this?

ejdziurka · June 11, 2021

More like 1 out of 250 times for me. But I have come back to the truck, and noticed it hasn't locked.

Fuelie · June 11, 2021

My 19 doesn't auto lock every once and a while, sometimes it seems like if I leave the door open for a extended period of time it won't lock. Not very often.

Tom

SummitWhiteT1 · June 11, 2021

my '19 NEVER failed to auto lock. When I got my '21 it started to do it like 1 out of 10 times. I have a theory it may have something to do with the fact that they removed the rear door buttons. I noticed that usually when it fails to auto lock it is because I opened the rear door and closed it last. Usually if close a front door last it will auto lock. Also, if it fails to auto lock after closing the rear door, I can open a front door, close it, and then the truck auto locks.

ram1067 · June 12, 2021

17 hours ago, SummitWhiteT1 said:

my '19 NEVER failed to auto lock. When I got my '21 it started to do it like 1 out of 10 times. I have a theory it may have something to do with the fact that they removed the rear door buttons. I noticed that usually when it fails to auto lock it is because I opened the rear door and closed it last. Usually if close a front door last it will auto lock. Also, if it fails to auto lock after closing the rear door, I can open a front door, close it, and then the truck auto locks.

This is the case with my ‘21 RST CC. I also believe it’s a timing thing. No big deal just have to wait till you hear the horn honk once……

todd308 · June 12, 2021

I've actually noticed lots of odd lock/unlock issues with my 21' compared to my 20'. My 21' also likes to beep the horn 3 times as if you've locked the keyfob in it when a door is still open, or when I first get into the truck in the morning, 20' never did that. It's almost like the truck either can't figure out a door is open/closed, or it gets confused if the keyfob is still in it or not.

I tried having the horn enabled on lock as an alert of it not autolocking, but it gets super annoying. When I'm working/loading the truck even walking around the truck the doors typically re-lock and beep the horn, about the 5th time that happens at 5am, no one is happy. It would be one thing if the truck didn't auto-lock till you were a few feet away, but by the time I'm at the tailgate it's already locking.

Seems like quite a few are reporting this on the facebook groups, but only for 21's as well so it seems like they definitely changed something. Seems like for every gremlin I escaped in my 20' I gained two in my 21'. Looks like GMC is going to repeat as winner of Consumer Reports Most Unreliable Vehicle award this year as well.

redwngr · June 13, 2021

I always touch the button on the handle after closing the door so I can watch it lock.

todd308 · June 13, 2021

Yeah, that's not a bad idea, I think I'll just have to get back into the habit of locking it with the keyfob.

Silverado4x4 · June 13, 2021

9 hours ago, redwngr said:

I always touch the button on the handle after closing the door so I can watch it lock.

And that's the winner as that is what I do, shut the door push the button on the handle just make sure in settings are for "all doors locked". When I return to the truck I just push the button on the handle and get in.

Z06JPB · June 13, 2021

I’ve had a 19 LT and a 20 LTZ and both worked flawlessly.

have 300 miles on my 21 LT TB and noticed this right away when walking away from the truck at work. Didn’t auto lock the first day and thought I missed a setting.

Confirmed setting and still have the issue happened at least a few times. Haven’t driven the truck much so haven’t experimented a lot but seems to happen when the rear door is opened for a longer period of time, like when I’m unloading my truck for work in the morning.

Auto lock always works when using only the driver door. Also if I open and close the rear door quickly, auto lock will work right afterward when it didn’t work initially.

Also potentially, auto lock may not be working after closing rear door and walking away from the truck to the rear diagonally at about 220 degrees. May be coincidence, but this is how I walk away from the truck at work and all times I’ve experienced no auto-lock I have been walking away in that same direction.

parked in the garage, after leaving the rear door open a bit to unload after work, I close the door and walk toward the front of the truck to get in the house. Auto-lock has worked every time.

with these observations, could be the proximity sensor on the truck is not optimally placed? I plan to do more experimenting when I have some time and an empty parking lot to test.

Edited June 13, 2021 by Z06JPB