Stoped to help pull someone out of hedge , connected winch, engine running flicked switch on remote engine stalled . Engine cranks not start no EML showing no fuel pump working . Checked all fuses , relays ,inertia switch . Thought might be ECU sent away couldn’t find any problems had it upgraded while it was there. Fitted back ECU still same problem, checked and cleaned all earth connections.battery in good condition. Anybody got any ideas ?

If the fuel pump isn't running and you have checked everything else then maybe it's the fuel pump itself?
Quite common to fail.

Unfortunately there doesn’t seem to be power getting to ECU, new fuel pump 9 months ago ! Thinking it might be a break in wiring loom ?

Could it be a break in the wire from the inertia switch?