On 23/10/2019 08:30, Tim+ wrote:

About 40 years ago my mother bought a Fiat 124 which was the first car I
ever saw with a boot light. I was demonstrating this to my future
father-in-law when we discovered it had no switch but was permanently on


Um, sounds like ******** to me. So the battery was running flat every day?

Tim


Car batteries don't run flat every day just because there is a 5W load
on them.
If yours do then buy a working one.