Head lights work or no power at all.
The reason I ask is I had the same thing happen to me in the summer .
It turned out to be a low charge in the battery because the car had only been used on short runs and had not had sufficient time to re charge the battery .
My advice to you is to try charging the battery in the car(dont remove it as you will get all sorts of code problems if you do )taking care to make sure your polarities are correct .
Put the charger on trickle-charge and just be patient ,It could be an over-night job.
What ever you do dont run a charge booster into it the
on lag 11 s is sensitive to voltage fluctuations(whatever the manufacturer may tell you so treat it gentle)
It may be that you have depleted the usable cranking voltage to below what will turn over your car .It is quite high on Diesels any way it wont harm trying to charge the battery the charger will tell you if its full or not
PM me and let me know how you get on