False Alarm Forward Collision Warning - 2021

[chaos]

I have a 2021 1500, 5.3L, tech package 1 and 2 (adaptive cruse, Heads up display, lane keep assist). Problem is a false alarm from the forward collision system that is I can replicate 100% of the time:

Any time the truck is decelerating while cruise control is on (example - down a hill, or you just adjusted cruse speed down using the roller) and you hit the deactivate cruise button - the forward collision warning goes off. It does this every time - regardless of the presence of a car in front of you. You can even do it in an empty parking lot if its big enough.

Can do it repeatedly over and over as well (at speed, set cruise to speed, then use cruise roller to lower target speed, then press cancel cruise button) - ALARM, repeat set speed, lower speed with roller, press cancel, ALARM...etc.

Got an appointment with the stealership Friday - going to have them look at this and a couple other things (shudder on low speed decel in drive that's widely noted but I want complaint documented, and climate control driver side number on dial is intermittently dim) - but curious if anyone else has a tech package equipped truck and can try it our of it i'm simply missing something.

Thanks!

 

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[chaos]

Update here - no update. Dealer on Friday appointment didn't have the time to look at the two complaints I had (despite keeping it for 3+ hours). Have to go back and drop it off next Tuesday....

Interesting point the service advisor said (so take it with a grain of salt) but GM only gives them 18 minutes per repair order to do a test drive to diagnose warranty issues. So this false alarm plus my shudder concern better be replicated in 18 minutes. If not I'll have to go visit the dealer and take the service manager on a drive to show them.

 

[chaos]

Update to the lack of update last time - still no update. Took it to dealer, they fixed the 'easy' issue - but said they 'could not replicate' the adaptive cruise issue. Told them to have a tech ready in 20 minutes and I'd show them the issue. Got to dealership, waited another 45 minutes for service manager to take a ride with me. Got in the truck, they had driven less than 1 mile because the odometer was on the same mileage (I didn't check the decimal). I was beyond unhappy.

Took dealer for quick ride down the road - replicated the problem 100% of the time, and at least 3 times in less than half a mile. Then replicated the shudder at 14 mph. Service manager said they had never seen either and would get with GM. That was weeks ago. Haven't heard back from them.

Side note - anyone know GM regional tech manager or similar contact info?