NHTSA Complaint #11428632 — 2017 DODGE DURANGO

The vehicle has a rear parking assist function. Via a Uconnect (touchscreen) system, the function can be enabled or disabled. The Uconnect system allows the operator to select whether the function will provide an audible warning or brake automatically if an object behind the vehicle is detected by any of 4 sensors installed in the rear bumper. The function can also be enabled or disabled via a physical button below the Uconnect system. I purchased the vehicle new and have owned the vehicle for 3 years. I have towed boats many times. Until recently, I was able to successfully use the touchscreen or physical button to disable the function when backing up with a trailer connected. Now I cannot disable the function or braking via either method. It appears to turn off for about 1 second before turning back on. I've tested in various conditions such as park/neutral, with/without a trailer, etc. to no avail. I thought I would try resetting software in the rear parking assist controller, so I disconnected both batteries and removed the proper fuse, but that didn't fix the issue. That got me worried because the failsafe should be that if the control system goes bad, the function should be disabled. I believe this to be true, because sometimes you need to back up to avoid collisions with irresponsible drivers, etc. If you are towing a trailer, you wouldn't be able to back up if the system failed. I understand about failsafe design from working on safety-critical aircraft computers. I reviewed the users manual and information online, and found that if connected to a trailer or exceeding 7 mph in reverse, the function should disengage. However, the function has NEVER, in 3 years, disengaged when towing a trailer, and I am unable to exceed 7 mph when towing due to the automatic braking. I tested this again by plugging a trailer into both factory-installed electrical receptacles provided with the tow package. I could not disable it. Other vehicle owners have the same issue.