2000 jaguar - the remote went dead. I got a new battery and I know I have to get that reprogrammed in order to use. My problem is that I can't use the key to lock the doors or trunk. when I lock it with the keys, it will lock but immediately unlocks and I am not able to use the key to open the trunk.
There are some vehicles that require a FOB reprogram if the battery is not replaces according to a procedure
Some manufacturers have a battery replacement procedure so key fobs, stereos and clocks do not have to be reset after the replacemnt.
I can not validate a 2000 Jaguar but I can say a 2013 Jaguar (yahg-u-r) does require a process driven battery replacement to prevent key fob reprogramming.
If you call a local locksmith, they will probably know if you need a reprogram or not.
Are you sure it's the fob? First, I don't believe you need to get the remote programmed for a battery change ... most cars are not this way. Second, when the locks pop back up, this is usually due to one of the doors being ajar. Could also be the trunk lid or the hood. Before you assume it's the remote (sounds like it's actually working to me or you'd get nothing), ensure all of the doors/trunk/hood are shut tight.