My wife phoned me today to tell me that while she was in the garden she heard the alarm start to go off on the S (in the garage). She managed to disarm it but when I got home I found the battery almost completely flat. Whilst sat pondering I noticed that one of the map reading lights was on.

Now the S was out for a run on Saturday and Sunday, in daylight, and seemed absolutely fine. Is there any channce that a tiny bulb could drain the battery in that time or have I a different problem?

And would the draining battery set off the alarm? I couldn't see anything else that might.

 

The battery will drain a *lot* quicker in cold weather.

 

I'd say that bulb could certainly drain a battery to the point of the alarm triggering in a couple of days.
Remove the battery and give it a good charge!...oh turn that map light off!

 

..and at the end of the day, it's only a small battery on the S.

 

Wot they sez is true.

Also, it's probably getting time for a new battery, if it's original.