Automatic Emergency Braking Problems of GMC Yukon - part 2

I was driving and all my sensors came on stating they needed service including front camera, blind spot notification, lane departure, emergency braking etc. Upon parking I exited my vehicle and walked around the rear of my car to find multiple wires hanging down burned from my exhaust. I took my vehicle to an automotive repair shop and not the dealer since it was no longer under warranty. They said they had never seen anything like it. It appeared the harness that holds the sensor module/wires disconnected from the car. It appears to be held in place with some sort of industrial glue. When it failed it was hanging in front of the exhaust and melted all of them. This disabled all of these sensors. I now have to pay for a new harness and to replace all of these sensors. In researching online it appears water intrusion has caused issues in some models and caused these harnesses to fail. I’m wondering if this is the cause even though this model isn’t part of the recall.

See all problems of the 2017 GMC Yukon 🔎.

On Wednesday, January 12, 2022, while driving from columbia, SC to cincinnati, we were heading northwest through the mountains of north carolina, on I-40, just east of the TN border. Traffic was fairly steady and heavy, so we were traveling at approximately 45 mph, in the right lane, winding through the mountains. Our friend, ** ***** was driving, my wife, ********* *****, was sitting in the right front passenger seat, working on her laptop, and I was sitting immediately behind her, also working on my laptop. With a semi-trailer truck slowing ahead of us, *** signaled to make a lane change into the left lane (this is only a two lane highway). As we were transitioning to the left lane, the vehicle suddenly – without any warning or driver inputs – slammed on its brakes, bringing the truck to a sudden and violent stop. Given the violent halting of the truck, we all assumed we had been rear-ended by a truck. The braking was so serious, luggage from the rear of the vehicle shot forward like a missile, striking my wife in the back of the head. She suffered what we believe to be a concussion, and she did seek medical attention in the days following the incident. Sitting behind her, the sudden stopping action caused me to twist my left knee, resulting in what might be a cartilage tear. I also saw my physician in the days following, and he acknowledged the swelling of the left knee. He advised me to monitor the knee carefully, and if the pain persists, to get an mri. The pain has not gone away, and I plan to get an mri in the next week or so. Our friend suffered a severely strained back in the incident, and has been treating his back with both ice and heat therapy. This was the third time this happened, each nearly resulting in a tragic accident. The dealer said "it's just a software glitch. " the "brake assist" program is clearly defective and unsafe.

See all problems of the 2021 GMC Yukon 🔎.

This new 2021 GMC Yukon denali we purchased on June 2, 2021 has a very sophisticated controls system that includes a feature, entitled "brake assist," that is designed to detect "rapid brake pedal applications due to emergency braking situations and provides additional braking to activate the antilock brake system (abs) if the brake pedal is not pushed hard enough to activate abs normally. " "brake assist disengages when the brake pedal is released. " after I left the dealership (June 2nd), I noticed that the "service brake assist" light had illuminated on the driver information center (dic). I pulled off the road to check the owner's manual, and then continued home trusting that no immediate hazard existed. I subsequently set up an appointment with the dealership for a checkup. A week later, the dealership downloaded a new software package from GMC. The brake assist light did not appear when the engine started, so I left for home (50-minute drive at moderate speeds). Enroute to my home, I stopped at a store and turned the engine off. Started home a few minutes later. While accelerating past 45 mph, the brake system independently engaged, which threw me against the steering wheel and into the windshield. As the SUV decelerated through 20 mph, the brakes automatically released. I was not hurt, nor did I lose angular control of the vehicle. I completed my drive home and parked the Yukon normally. Did not drive it again until returning to the dealership a few days later. This second visit did not bear fruit. After significant explorative work, the lead mechanic drove the vehicle several miles under a multitude of conditions, but could not duplicate the problem or get the light on the dic to extinguish. At my request, the dealership returned possession to me with the light still illuminated. I have driven the vehicle several miles since then with the "service brake assist" light still illuminated. I suspect this is a GMC software problem.

Driving approx. 62 mph on a highway, went to slow down and unable to brake, upon pushing down on the break there was resistance, after pumping the breaks multiple times I was eventually able to slow down with a lot of force. Messages on dashboard read "brake system failure" "62 max speed esc, service esc, service trailer break system, and forward collision system unavailable. " abs, esc and check engine light all illuminated on dash screen.