2010 Mini that began making rapid clicking sounds in the passenger side fusebox and would not start. Crank a bit but not want to fully turn over. Battery, alternator, starter good, but whatever problem does seem to drain the battery if not used for a few days. Once it starts it runs fine no problems.
I've read through the various threads referencing CAS module and removing the fuse box to address corrosion (likely possibility since in hot humid area and probably has leaked along the way with sunroof etc).
That said, the one temporary fix I've found, is if I remove the two start/stop fuses (40v and 5v) and then put them back in, it starts fine. Turn it off and try it again and the clicking resumes and less likely to start. Try a third time and it's likely going to be back to the all clicks and no start.
So what is it about removing and reinserting the start/stop fuses that temporarily fixes/resets it? And does that give any clues as to what the underlying cause is?
Thanks!

 

Replace the battery.

 

If it were a primary battery issue, why would removing and re-inserting the start/stop fuse address it each time?

 

Odd and unusual things happen when a MINI's battery can't hold charge. Replace the battery and then go from there.

 

The JBE goes bad in these models. I had mine replaced earlier this year. Not sure if this is your problem, but that fuse box/JBE is known to have issues with the low pressure fuel pump (LPFP) relay on one half of that circuit board (there are two stacked circuit boards within the housing).. the JBE can either be repaired or replaced. Mine first presented itself by the car stopping running, then it started again.. then it failed to start at all. Hope this helps.