If it's the fuel pump relay clicking when you turn the ignition on, it shows that the relay is working and being fed, by ecu and live supply.
So we are down to the OUTPUT from the relay, which is on terminal 87, look at relay to see which slot is 87, and when a live is put in that slot does the pump then work ?, if it does renew relay, if it doesn't there is a break in the wire from relay to the fuel pump.
Terminal 30 or 30/51 is the permanent live supply to the relay(not the ecu one), so make sure this is present, use this feed to supply terminal 87, as that is all the relay does join them two together, pump should run.
tabetha