There are quite a few sensors that come back from the engine to the Engine ECU, there are only Two that will stop it when the engine is running, the one that stop the engine are 1/ Earth feed back to main relay and if the main relay goes out then so does your fuel pump relay, all other sensors...

I have owned a Discovery 2 TD5 for about two months now and it has spent more time in the garage and behind the RAC ( God Bless Their Cotton Socks) than i have actually driven the dam thing, gradually loosing the plot with the car, and just when i was about to fire bomb the thing a ray of sun...