Key fob lost inside car

[petstk]

Hey, I couldn't really find a similar case, so I'll try a new post.

I got into an interesting situation. We went on a trip and now the key is lost inside the car. I'll describe my train of thought as to why I insist it's inside the car and if anyone has any idea where to look or what to do, I'd really appreciate that.

1. Car started with fob in a jacket pocket on passenger seat. Jacket then moved to back seat. No signal about no key detected.
2. Short travel, stopped to tend to a fussy 3 year old for 2-3 minutes. On departure again no signal for no key detected.
3. On arrival, car would not lock and would chime to signal "key inside". However would not start due to "Key ID incorrect"
4. After a few minutes it would no longer chime from the outside, but would still show "Key ID incorrect".

Luckily I had someone who could bring the spare fob from home. Car started and is working normal now, however if I take the spare fob out of the car, now it says no key detected.

Any ideas as to where I might begin to look? I've already gone through glovebox, taken the plastics off in the front footwells adjacent to the doors, checked between the seat and backrest, under seats, taken all the floor mats out, took the back seat off its brackets, still nothing...

Car is J11b Tekna+ if that matters at all in this case

[trout]

Not gone through a hole in your jacket pocket?

[petstk]

I forgot to mention that… all pockets were turned inside out, checked for holes and are made in a way that anything that falls through falls out, not inside the lining. That’s why I’m focused on inside the car

[andy2019]

So your unable to lock the car then ??

[petstk]

After a full night in sub-zero temps, it only now recognizes it when trying to start the car. I can lock it with the spare fob, but not with the door buttons.

Thing that makes me believe main fob is inside is the “key id incorrect” message I get. Otherwise it doesn’t say that if there is no key inside.

[andy2019]

It wont let you lock the car normally if the keyfob is inside the car. Try changeing the batt in your spare key fob as they only last a yr normally.