Cadillac ATS shifting on its own, help!

Hoping someone here can help me. I have a 2014 ATS, about 50K miles. Sometimes while I’m driving, the car will go from Drive to M1 or M2 gear without me doing anything. There are no shift buttons on the wheel, and I definitely didn’t shift gears myself. If I try to shift the gears to get it back in drive nothing happens. Reverse neutral and park all work, but the screen will still show M1/2. Turning the car off and back on will bring it back to normal sometimes, but there have been times I’ve just had to wait for a few minutes before I could drive normally again.
The dealership said no codes came up when they ran it for that
Any idea what can cause this??? The car is currently at the dealership, and of course this didn’t happen when they checked it out so they’re saying it’s fine.
I don’t know much about car maintenance but someone suggested it may be a PCM issue?
any advice would be appreciated. I’m supposed to pick the car up tomorrow but I want to be sure they checked everything that could possibly cause this before I pay them for essentially renting a loaner car for a day. Thanks in advance

Sounds like a PCM problem but it could be something else. Wiring, or a bad button or… lots of things.
Problem is… WE can’t lay hands on the car, scan the PCM while this is going on, or experience the problem. The dealer can.

That is the only way this problem is going to be fixed. And the tech better be pretty good at diagnosis or the rental car is going to be pennies compared to the parts that could be thrown at this problem trying to fix it.

I wish you the best of luck. Post back with what the dealer finds and tell us what they did.

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The dealer looked at it and they said they didn’t find anything wrong. The car ran fine when they drove it of course, that’s why I came on here for advice, maybe one of you guys would suggest something they didn’t check.

Obviously this isn’t something I can’t ignore, and them saying they found nothing wrong is just unacceptable.

Thank you for your reply, I don’t know anything about cars besides how to drive them so I appreciate the help! I’ll post back here after I see them tomorrow…

Just picked the car up, they said they couldn’t find anything wrong. I drive the car to Wendy’s, while I’m waiting in line I notice the car had moved to M2 mode so I took a video of me attempting to change gear and sent it to them, hopefully this will help get me an answer.

Lemme ask you… The screen changes to M2 mode, but does the car drive any different? Shift funny? Not shift at all? Or is it just the display that changes on its own?

BTW, the advice you got on the Cadillac Forum regarding the center console shifter replacement sounds like a real possibility.

The speed drops a little bit, and when you hit the gas it’s a loud revving sound(not sure if that’s the right word But best description I can come up with) I’ve always pulled over and waited for it to go back to normal when that happens, doesn’t seem like driving that way is good for the car.

I have to get my brakes done soon so I’ll have him look at the shifter while he has the car in there.

I don’t have an answer, but I do have a question-what is M1 and M2? Are they first and second gear in manual mode?

Sounds like when it SAYS M1 or M2, it really IS in first or second gear.

I suggested a scan because with no error code, you could at least see what command the transmission is actually being given irrespective of the gear shift lever setting. Makes me think the gear lever switch is bad. If the shifter really is $114 as the Caddy Forum says, I’d say that’s the cause and replacing it is the (cheap) fix.

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Hopefully it’s the gear switch, I can live with that price! I’ll post back here next week after my regular mechanic checks it out while he’s changing my brakes.

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