i would to keep a key fob in my truck with the battery not in it, for emergency use, i will use the key to open the door, will it work from the truck battery if i put it in the right area of the consul, thank you, richard

If you have a tow hitch there's an other option. You can keep it securely stored in a lockable safe that fits inside your tow hitch.
This way you don't need to remove the battery. The safe is small water tight and a combination opens it.

please explane, is the a safe that i buy that goes in the receiver ??

Yes, like these

https://www.walmart.com/ip/HitchSafe...E&gclsrc=aw.ds

thank you, not sure if i trust the combination, maybe get froze, i will look for a keyed one, thanks, richard