I searched on this and found a relevant thread, but it was three years old and didn't solve my problem, so here goes.
'22 Bolt EV 19 months old and 27,500 miles.
My key fob (the one usually used) stopped working today. Won't do anything and car says "Remote not detected". My wife's key fob (which spends most of it's life in her dresser drawer and hasn't actually been used before today) works fine.
I changed the battery, and checked the contacts to make sure they're clean and in good shape. New battery tests 3.26 volts. Still not working. My cell phone is in my shirt pocket and the fob is either in my pants pocket or in my hand.
I put the fob in the "dead fob spot" in the center console and the car starts.
All this is happening in my garage where there should be no RFI.
Anybody had this happen? The only thing I can think of doing now is take it to the dealer.
That's probably the best thing to do. Make sure you let them know you already tried to replace the battery. If it's under warranty, and as long as you have a spare, make it their problem. Be prepared for the dealership to accuse you of abusing the fob in order to avoid a warranty replacement.
So I don't mean to offend, but there have been 2 other posters with key fob problems who later realized they inserted the battery the wrong way. It may be worth double checking the battery orientation.
I had this problem early on and it was because I activated KeyPass. once I deactivated the KeyPass feature, I never had the undetected key fob issue again.
What is KeyPass? I can't find it anywhere in the OM. Is it an OnStar thing? I don't have a subscription other than the basic Connected Services included with the car.
I didn't want to risk screwing up my one remaining working fob, so I tried another new battery from a different package I bought yesterday (still an Energizer). Still doesn't work.
I've got an appointment at the dealer tomorrow afternoon. We'll see what happens.
OK, time to eat crow. Sometimes you see what you want to see and not what you should.
I did, in fact, put the battery in backwards. I guess I’ve seen so many other devices with the positive side up that my brain transplanted that image.