Tailgate spontaneously opening

Kimberly4398 · December 1, 2021

I am having the same issue with my 2021 Trail Boss. The tailgate just randomly opens and the locks/lights click/blink randomly. The only time it doesn't happen is when the truck is in gear and/or locked. I've had it into the dealer three times now and they cannot figure it out. I'm afraid it's going to come down on a car parked behind me and cause damage, or worse - on a small child. As for the fob, I've tried leaving the fob out of my purse and it makes now difference if the fob is being touched or not.

***UPDATE*** Dealer replaced the tail gate switch and so far it's staying up. Fingers crossed.

Edited December 3, 2021 by Kimberly4398

jsward12 · December 1, 2021

7 minutes ago, Kimberly4398 said:

I am having the same issue with my 2021 Trail Boss. The tailgate just randomly opens and the locks/lights click/blink randomly. The only time it doesn't happen is when the truck is in gear and/or locked. I've had it into the dealer three times now and they cannot figure it out. I'm afraid it's going to come down on a car parked behind me and cause damage, or worse - on a small child. As for the fob, I've tried leaving the fob out of my purse and it makes now difference if the fob is being touched or not.

Go to page 1 post from March, this is a well known issue. Seems to be an issue with upper tailgate switch.

Epsilon Plus · December 24, 2021

I have seen on FB where people with non-Flex, standard gates have the dropping issue. A few reported it's due to the little drain holes in the upper trim that let water short out the switch that's directly below it. I also noticed someone posted a pic of thier 2020 and it didn't have the indentation at the top of the gate. Also seems like most having issues are 21+ where the Flex gate became an option. Is the indentation part of the multiflex and they are just using the same tailgate cap, but with nothing in there? In that case they don't want water to pool and put the holes? Or possibly the holes (shaped like triangles) are to snap something in place related to that gate?

Either way, I used some clear silicone to seal them up. Rained today. Sure enough water pooled in the pocket so the silicone sealed it. Much preferred to the water dripping down directly on the switch/electronics.

So, if it's related to gate drops, sealing the holes or buying and putting on a non-indented/pocketed gate cap might be the resolution.

Edited December 24, 2021 by Epsilon Plus

Esloany · December 29, 2021

Googled tailgate randomly opening cuz my boyfriend is having the same problem.

2022 Silverado 2500, at first I thought he hadn’t closed it right. One day we were standing outside the truck, which had been parked for about 20 minutes, keys were in the cup holder, and I heard a bunch of clicks from the latch and it just opened.

another time it opened while we were driving (again, keys in the cup holder).

today, he said it opened 4 or 5 times on him.

I’ve been driving newer chevy’s for a while now, and I noticed the infotainment system gets a little wonky in the cold and the rain. Was wondering if it had anything to do with the computer?

jsward12 · December 29, 2021

Welcome! Read through my earlier posts with the remedy. Seems to be related to faulty switches and potentially the dampeners being too tight which may short out the switch as well. My dealership replaced both and been working fine ever since .

Kellster · January 24, 2022

I have a 2021 GMC Sierra SLT and my tailgate was doing the same thing, only while parked. It seemed to be only when the key fob was away from truck for extended periods. Dealership had never heard about this(??), and couldn’t replicate the issue, of course. They did however, at that appointment, change out the entire tailgate handle due to a “short” and I am going on 2 weeks of it not happening since. It would do it to me daily for almost 2 weeks before I took it in. Hope this helps.

Michael parrette II · March 7, 2022

My tailgate on my 2021HD Gas, just started to drop whenever. Have an appointment in couple of days, of course this is the 1st they have heard of it happening.

Tedb · March 15, 2022

I have same issue with 2021 GMC Denali 2500. Gate opens itself numerous times and other times gate switch does not function properly. I have noticed on the top of gate there are two holes directly above the switches I gather are for drainage of water. My question is if water drains onto the switches or wiring could it be causing a short in switch?

RKGMC · April 18, 2022

2021 GMC 3500 black diamond, same issue with my tailgate, random opening. Took it into dealer, they were aware of the ongoing issue and ordered a replacement switch for the tailgate. Of course on back order, they removed the 4 relays in the drivers side fuse panel until the part comes in. For now I plug in the relay to open the tailgate.

Loren Riether · May 3, 2022

On 4/18/2022 at 4:02 PM, RKGMC said:

2021 GMC 3500 black diamond, same issue with my tailgate, random opening. Took it into dealer, they were aware of the ongoing issue and ordered a replacement switch for the tailgate. Of course on back order, they removed the 4 relays in the drivers side fuse panel until the part comes in. For now I plug in the relay to open the tailgate.

Can anyone provide the part number(s) for this fix.. I am having this issue as well.. would rather not have to goto dealer..

mijibage · May 18, 2022

Top switch is #85521472

Bottom switch is #84758464

I've replaced both on my 21 3500HD AT4. So far so good.

4x4Hank · August 9, 2022

Hi guys. 2022 Sierra 2500 here and a new member of the dropping (inner) tailgate club. My upper switch takes about 20 pushes to get it to work. Sometimes the dash tells me that the inner tailgate is open but it appears that the tonneau seal keeps it from actually opening all of the way. The disable feature for the inner tailgate so it doesn’t hit the hitch isn’t working either. It’s my understanding that this is a feature only on the 2022’s but I’m not certain about that. Seems like the upper switch is the culprit here but I go to the dealer tomorrow to see what they say.

21 1500 AT4 carbon Pro · August 29, 2022

On 5/2/2021 at 10:54 AM, dw_6.2L said:

I’m having the same issues with the power tailgate going rogue randomly when in park.
Any confirmation on the fix? Thanks!

I have an appointment next week for this and the parking assist randomly turning off (under perfect weather conditions). 200 miles on the truck, less than a week old.

Any idea on what the issue was on your rear parking sensors turning off randomly ? Truck is currently in the shop for the tailgate dropping on its own, read parking sensors sometimes not working and read cross traffic alert not working also…. I am wondering if the wiring harness is messed up?

ssgballistics · August 30, 2022

Does anyone have this issue on the regular power tailgate, not the multi-flex? My tailgate has opened on its own on four different occasions. On the third occasion, it was backed into the garage. My wife walked out to find the tailgate repeatedly opening and closing over and over. There is no telling how long it had been going. Caused some body damage due to the repeated hitting of the hardware on the door at the back of our garage.

newdude · August 30, 2022

1 hour ago, ssgballistics said:

Does anyone have this issue on the regular power tailgate, not the multi-flex? My tailgate has opened on its own on four different occasions. On the third occasion, it was backed into the garage. My wife walked out to find the tailgate repeatedly opening and closing over and over. There is no telling how long it had been going. Caused some body damage due to the repeated hitting of the hardware on the door at the back of our garage.

Its the same as others have had in this thread, bad switch. Water gets in from the two drain holes in the center "hand pocket" at the top of the gate and shorts the switch out.

Edited August 30, 2022 by newdude