2017 GMC Acadia Limited electrical system problems

“Cannot shift out of park. AC stops blowing also. Electric seats stopped working. Replaced BCM modular, solenoid , entire shifter and more. It worked for two months. -Happening again. Cannot shift out of park and the AC stops working. Seat are working at moment. It’s all intermittent. Currently dealer will not help me. No warranty anymore. Im on a site where thousands of gmc’s have this same problem. Im gonna have to bring back to another dealer but no one can figure it out how to fix this. I sent my last bill. I also had one before that with the shifter assembly and solenoid replaced. I cannot find at moment”

“I’m just reporting several known issues. First, with code P2138, which I got today at Oreilly after my car started throwing warnings. I used my parking brake briefly and afterwards got the following warnings on my car: “Steering Assist is Reduced, Drive with care”, “Engine power reduced” , “Propulsion Power is reduced” , “Service Parking Brake”. I’ve never even had one of these warnings. I’ve only gotten “shift to park” which is another known & common issue. With this P2138 code, it can affect acceleration and essentially loss of control over it, but seems I suddenly have several issues. Recently the infotainment system is possessed, touch screen stops working, it calls people by itself, beeps and scrolls by itself and is essentially useless. Might as well be driving at 1997 something or other, at least I could play a tape or CD. This is Denali trim at 87K miles. Primarily though I’m concerned with this code, if it’s legit, it is very dangerous. How unreliable and unsafe to not know.”

“After shifting to park and attempting to turn off my vehicle, I receive an “Action Required Shift to Park” error message. I’m assuming the vehicle is in park but I’m not certain and worry about it moving or rolling. It is difficult to get it to turn off by jiggling the shifter and turning the vehicle on and off. At times, I am not able to get it off and then the vehicle will not lock and the battery goes dead. According to my VIN there is not an active recall but brief internet search states there has been numerous reports, recalls, and lemon law returns due to this.”

“The contact owns a 2017 GMC Acadia. The contact stated that while attempting to turn off the vehicle, the vehicle failed to turn off. The contact shifted from park (P) to drive(D) and was eventually able to turn off the vehicle. The contact stated that the letter P(park) was outlined in yellow and was illuminated on the instrument panel. Additionally, the contact stated that while attempting to close and lock the driver's side door, the door failed to lock securely. The contact stated that the failures occurred simultaneously. The contact stated that the failures were intermittent. The contact had not taken the vehicle to a local dealer or independent mechanic. The vehicle was not diagnosed or repaired. The manufacturer was not informed of the failure. The failure mileage was approximately 74,000.”

“Twice the shift to park function of the vehicle has failed, once in 2020 and again in 2025, it appear that there is a recall for the year make and model vehicle, but for some reason my particular VIN in not included in this recall. The recall needs to be expanded to address this safety issue.”

“The contact owns a 2017 GMC Acadia. The contact stated that after shifting to the park position and attempting to turn the vehicle off, the engine shut off but the headlights and dashboard lights remained illuminated. Also, on multiple occasions, the battery had drained and the vehicle had to be jump-started. The vehicle was taken to the local dealer who diagnosed that the floor shifter harness was faulty and needed to be replaced. The floor shifter harness was replaced and the failure was remedied, but approximately two years later the failure reoccurred. The vehicle was taken back to the local dealer. The contact was informed of the manufacturer's TSB to repair the failure and a new and improved floor shifter harness was installed which corrected the failure. The contact indicated that the manufacturer was aware of the faulty harness but no assistance was offered. The failure mileage was 45,000.”