TLDR: Both key fobs unexpectedly stop working? Pull disconnect/reconnect the battery. or Pull and replace Fuse 57 in the rear cargo area.

So this morning I go out to the garage to take the kid to school. Key fob doesn't unlock the door. I have a case on my key and couldn't get to the emergency key (lesson learned for the future lol). But I was able to unlock it with the app on the phone. Get in, car wont start unless I put the key up to the steering column.

Went back inside to get the second key. - No luck
Bought two brand new fresh batteries - Long shot, but no luck.
-Called up dealership to make an appt-.

Start looking around online. I found an old thread from 'the other big defender forum' that effectively said, check the fuses.

2023 Defender iGuide, has no mention of Keyless Vehicle Module on the Fuse diagram for some reason. But, in the 2020 Defender iGuide that was linked in that thread, it mentions Fuse 43 and 57 in the rear cargo fuse box.

So this afternoon I go out, find 43 not there. But, 57 is. 5A. I pull it and replace it with the spare in the fuse box. And voila... it works.

I do not get why the fuse would go bad in such a new truck, nothing got wet, haven't screwed with any wiring. So just for ****s and giggles I put back in the old fuse. And... still works.

So, effectively I guess I needed to hard reset this thing which probably could have also been done by disconnecting the battery for a few minutes.

But. What a random *** issue to deal with. Thankfully I have some minimal time/patience to look for solutions and was successful this time. But what do 'normal' people do? Visit the dealer once a week for random **** like this?

 

Very interesting. I have one key that won't unlock the doors with the buttons on the door. It'll allow me to lock the vehicle with the door buttons, but not unlock. That same key fob will lock/unlock, pop the rear door, and start the vehicle. Just not unlock with the door buttons.

Fob two works flawlessly for all functions. My GAP tool is in transit so I'm going to wait to see if I can see any codes and maybe clear any modules that aren't happy. If that doesn't work I'll pull fuse 57 and see if that works.

I agree with the question "what do normal people do?". I too don't mind tinkering even under warranty. I'd rather give it a shot than make an appt and waste several hours trying to get in for service for them to not tell me what they did, and only tell me they "cleared an error" if even that.

 

Have you had any luck fixing that one key FOB? I have the exact same issue with a CPO 2020 X I just purchased. The FOB won’t unlock doors 95% of time when I press button on door handle. It will lock them by pressing door handle button, and will unlock + lock using buttons on FOB itself. I even added fresh CR2032 batteries with no luck.

one or two times I even had the message on dash after entering vehicle, “No Key Fob detected in vehicle”.

 

I cleared some errors with the GAP tool yesterday and the fob started working again. I only unlocked it a couple times, but it did work so now I'll have to see how long it lasts.
I had a couple BCM and door errors along with the regular errors that seem to accumulate. Nothing was obviously the lock or fob though.