2018 GMC Acadia electrical problems

Filed Nov 2, 2026 · Electrical, Engine · WV

Our vehicle’s horn beeped and a message on the dash said vehicle not in park. I copied the following from your web site and am requesting an update: General Motors has acknowledged the "Shift to Park" issue through several Technical Service Bulletins (TSBs). While there hasn't been a formal safety recall for this specific shifter issue as of early 2026, a class-action lawsuit has been filed alleging one is needed.

Filed Sep 29, 2026 · Electrical, Engine · PA

I get error electric Steering assist reduced or unavailable drive with care at around 84234 miles on my car . Upon looking up problem on Internet it has to do with the Thermostat. I also found where Gm has a bulletin N252508350 which only seems to cover certain vehicles with the same problem. This seems to happen at all different miles driven on vehicles. I don't see how Gm can get away with only fixing certain vehicles with this safety problem when it shuts down the electric steering assist . This problem from what I can find on the internet is common to all years from 2017 up in Acadia with the 3.6L engine . The Thermostats seem to be defective and I feel Gm needs to address this problem for all of these vehicles . Not just for there special bulletin N252508350 which covers some vehicles in 2021with 3.6L engines. If the engine design was like the old engines and easy to replace the Thermostat by just taking out 2 bolts , I would say no problem I will replace it .But when you have to take half the Engine apart just to replace a 20.00 part that is defective that affects the steering of the vehicle, they need to have a safety recall.

Filed Jun 8, 2026 · Electrical, Lights · OR

Shift to park Malfunction again, 4 th time!! 1000$ to fix is ridiculous

Filed May 21, 2026 · Electrical · KY

Shift to park error Vehicle won’t shut off

Filed May 15, 2026 · Electrical · MI

For the last 6 months, I keep getting a "shift to Park" message on my dashboard indicating that my vehicle is not in park (in which it is). The problem is getting wors, so I called GMC on 5/14/26 to inquire and was informed that my VIN number WAS not include in the resent class action lawsuit for this issue. I then found out by searching myself on line for other complaints that GMC is very aware of this situation and yet refuses to fix the issue free of charge to customers. According to TSB 19-NA-206, t does list my year , make and model of vehicle affected by this faulty part. On 5.15.26, I called the dealership to inquire and was informed that my VIN was not covered under warranty (which I had already known), and that that service I would have to pay lots of money out of pocket for it. The service tech did look in the system and claims (without me even knowing that they had did that repair already....He lied I'm for sure). I informed him well if they did repair that part, and I'm still getting an error message about the same thing, clearly its faulty and the dealership should be responsible for fixing it. This was not the case as I was informed it would have to be out of my pocket. This mess is unfair! GMC is well aware of this faulty pat on vehicles, and to refuse to fix it free of charge is just down right hurtful! GMS is responsible for repairing this part on everyone's vehicle as it is a hazard to everyone and the community to have a vehicle unstable to be able to slide away from a parked position. This is such a road hazard, something has to be done about it. It's not far that I am expected to pay for these faulty wiring costs out my pocket when its a faulty issue GMC is very well aware of.

Filed Apr 27, 2026 · Electrical, Transmission · AK

The contact owns a 2018 GMC Acadia. The contact stated that while the vehicle was parked and turned off, the “Shift-to-Park” warning light illuminated with a continuous audible alert. The vehicle was unable to recognize that the transmission was in park(P). Several attempts were needed to shift to park. The battery was disconnected to turn off the audible alert. The contact stated that the vehicle was previously repaired under an associated recall. During the recall repair, the shifter and wiring harness were replaced with Part Numbers: GM84955381 and GM84733196. The manufacturer was not notified of the failure. The failure mileage was unavailable.

Filed Mar 18, 2026 · Electrical · PA

Vehicle dies with no warning, no warning lights, no power even emergency flashers are inoperative, almost like it got hit by an EMP

Filed Mar 17, 2026 · Electrical · TX

My car says Shift to park when I try to turn it off. Leaving my battery to drain.

Filed Mar 12, 2026 · Electrical · CA

Car does not turn off, says “Shift to Park” but car already is in park and car won’t turn off.

Filed Feb 7, 2026 · Brakes, Electrical · TX · crash

The vehicle has experienced repeated electrical and engine-related malfunctions, including random engine shutdowns while driving and random no-start conditions. The thermostat and cooling system failed and were replaced in 2024. Multiple sensors have failed. The braking system remains noisy even after brake replacement. The lane detection safety system does not provide audible alerts. The vehicle is currently operational and available for inspection upon request. How was your safety or the safety of others put at risk? The vehicle has randomly shut off while driving on both highways and city roads in Azle, Texas. This occurred while my two children were in the vehicle. When the engine shut off, there was a risk of losing power steering and braking assist, which could have caused an accident, especially at highway speeds and in traffic. Has the problem been reproduced or confirmed by a dealer or independent service center? The thermostat and cooling system failure were confirmed and repaired by a service center in 2024. Electrical and sensor issues have occurred repeatedly but have not been fully diagnosed or resolved. Brake noise persists despite replacement. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives, or others? UNKNOWN. The vehicle has been serviced by repair facilities, but the manufacturer has not provided a definitive diagnosis for the engine shutdown and electrical failures. Were there any warning lamps, messages, or other symptoms prior to the failure? When did they first appear? Yes. Various warning lights and symptoms appeared prior to failures, including cooling system warnings and sensor alerts. Electrical issues and battery failures have occurred repeatedly, with batteries lasting only 2–3 years. Symptoms began after purchase and have continued throughout ownership. Additional details The brakes have been noisy even after replacement, and the lane detection system does not produce audible warni