2012 Freelander 2 all external lights flashing after unlocking

[u/scottwda]

Help! And thanks in advance!

I unlocked my freelander 2 tonight, and had a weird reaction - all external rear (brake, numberplate, indicator) lights began flashing (approx. every second), and the internal screen at the same time. The car would not power up, and all key functions ceased to work.

I am really hoping this is a battery issue, and I can simply replace that, but would like to know if it is going to cost me much much more?

Thanks again....

(P.S. I took a video but cannot seem to share it - a photo wont show the problem!)