Please help, mk6 fiesta has died, hopefully temporarily. Lights were fading and electrics cutting out last week, now won't start at all. Ignition goes on, starter clicks but nothing happens. Have checked battery, changed alternator and starter, cleaned earths, what's next? 

Your issue sounds a lot like what I’m having happen at the moment. I have narrowed it down to somehow when my battery died the immobiliser activated. Check the light between your fuel and engine temp gauges there should be a small red light if it is solid then goes off it’s good if it’s solid and stays on or flashing fast then it’s definitely your immobilise. Unfortunately I still haven’t managed to get mine to deactivate but I have until 4 January to get her going again, so I’m currently researching how to deactivate it without paying out hundreds of pounds