‘20 GMC Sierra Denali Park Assist Disabled

KL Fopono · January 6, 2020

Park assist won’t turn on. Button doesn’t turn it on.

If I navigate to the vehicle settings tab through the console, it says “on” however it does not light up the button.

I switched it off and on again through the console, the button lights up for a few seconds and turns back off.

I did manage to get it into reverse after turning it on and it does work, but turns itself off after about 3 seconds (regardless of what gear I am in).

Started after I used remote start, turned truck off and tried it with and without remote start, no dice.

Any input?

Sent from my iPhone using Tapatalk

Daniels79 · January 6, 2020

Did you recently get the recalls done? Mine was disabled after they did the recall update on the front camera.

Edited January 6, 2020 by Daniels79

19 Denali ultimate · January 8, 2020

You don't mention if your truck is clean, recently washed, it is cold where you are? The reason I ask that is if the sensors are dirty they system will act exactly like that. Also if it was recently washed and it is cold there could be a thin layer of ice or even soap film left on the sensors from the car wash. I know it sounds stupid but these have all happened to me with the exception of the soap film. Good luck and keep us posted if you get it figured out.

hddude · January 9, 2020

Have the same issue with my 2019 RST Crew Cab. After a rear bumper fender bender, one of the sensors was damaged, mostly cosmetic it appeared. It was still operational. After the recent heavy storms in SoCal, it was non operational, just as described by the Op. I recently had the rear bumper and sensor replaced by a collision center, still non-operational. I tried removing the battery power for 30 min., hoping to reset the control unit, unfortunately, no change. The collision shop is telling me there is nothing they can do to correct the issue, which I find hard to believe considering they were an authorized center from the insurance company. I checked the underside of the bumper to make sure the connectors to the sensors were secure, they appear to be. If someone has any tips or fixes we can make ourselves, short of having the dealer service it, it would be greatly appreciated.

Wormydog1724 · March 12, 2021

What was the remedy to this? Just dirty or something else?

Paul Bergeron · April 12, 2021

My 2021 GMC 2500hd is doing the same thing. Rear park assist works sometimes.

Paul

TechSavvy2 · June 16, 2021

On 4/12/2021 at 6:16 AM, Paul Bergeron said:

My 2021 GMC 2500hd is doing the same thing. Rear park assist works sometimes.

Paul

Looking for answers as well, I have same message as you. Vehicle is 2021 Sierra 1500 Denali. Brand new. Has about 200 miles on it, has done this since I purchased it. Vehicle is completely clean, no debris, no water, so soap. Works once in a great while, but this "Rear Park Assist Off" pops up in the display almost every time I drive the vehicle, from seconds after starting it.

gemarsh · June 16, 2021

The only time I receive this dic message is when I have a trailer plugged into the 7 way.

Any chance this 7 way could be damaged? I highly doubt it, but could the port be dirty and then get moisture in it turning to mud and making a resistance, making the dic think there is something plugged into it?

I have the trailer camera ports above the 7way. I think some trucks have a 4 way flat instead. Could that be causing issues?

TechSavvy2 · June 16, 2021

7 hours ago, gemarsh said:

The only time I receive this dic message is when I have a trailer plugged into the 7 way.

Any chance this 7 way could be damaged? I highly doubt it, but could the port be dirty and then get moisture in it turning to mud and making a resistance, making the dic think there is something plugged into it?

I have the trailer camera ports above the 7way. I think some trucks have a 4 way flat instead. Could that be causing issues?

I'll check on this - I go through drive-thru car washes almost daily, maybe soap/water got sprayed up in the plug port. I'll check it out, good looking out man!

But beyond that, you've never seen the "rear park assist off" message pop up at all, not a single time other than trailering? (identical to Paul Bergeron's image above). I ask because I was digging through the manual last night wondering if by chance maybe it pops up when you go above the 5mph limit or drive forward or something to deactivate it. But sounds like it shouldn't even be popping up then judging by your wording....

TechSavvy2 · June 26, 2021

On 6/16/2021 at 12:57 PM, TechSavvy2 said:

I'll check on this - I go through drive-thru car washes almost daily, maybe soap/water got sprayed up in the plug port. I'll check it out, good looking out man!

But beyond that, you've never seen the "rear park assist off" message pop up at all, not a single time other than trailering? (identical to Paul Bergeron's image above). I ask because I was digging through the manual last night wondering if by chance maybe it pops up when you go above the 5mph limit or drive forward or something to deactivate it. But sounds like it shouldn't even be popping up then judging by your wording....

Turns out it probably isn't that - the port is completely clear and brand new looking. No water or soap anywhere to be found in it.

Will have it back at the dealer next week for a few other fixes, this is on the list to be fixed as well. Even though they said they couldn't replicate the problem last time they had it, but I find that hard to believe since it pops up every time you start the vehicle and every couple minutes thereafter as well....

VvTheGoodLifevV · November 3, 2021

Is there an update to this? I have the same problem with my ‘21 Silverado. TIA

TechSavvy2 · November 3, 2021

3 minutes ago, VvTheGoodLifevV said:

Is there an update to this? I have the same problem with my ‘21 Silverado. TIA

Yes - they ran real-time diagnostics on it and reproduced it a handful of times. The rear bumper sensors were “detecting” objects behind the vehicle. Turns out there was a TSB on the small circle round pieces that the parking sensors are mounted inside of being wrong / bad. They replaced all of those and it fixed the problem.

Scomo67 · November 3, 2021

9 hours ago, TechSavvy2 said:

Yes - they ran real-time diagnostics on it and reproduced it a handful of times. The rear bumper sensors were “detecting” objects behind the vehicle. Turns out there was a TSB on the small circle round pieces that the parking sensors are mounted inside of being wrong / bad. They replaced all of those and it fixed the problem.

I have a '21 Silverado LT and this message pops up when I release the brakes after stopping more often than not. Do you have any information on this TSB?