I've tried a quick search on here but didn't find anything that seemed to directly answer my question so I hope you don't mind me trying your patience with what must be a common question...
I have two ignition keys, each with an immobiliser fob (black, lozenge shaped with a lock and unlock button on the front). The fob I use most often has now stopped working but luckily the other does still work.
Is a fob battery change a simple process or does it involve re-programming keys etc?
Grateful for any advice.