No Power To Fuel Pump

I have an x308 3.2 97 Sport,
It has sat unused for a year or so but has been started a couple of times in that period,

I put a fully charged battery in it and it cranks fine but won’t fire,
I checked the shreader valve for fuel pressure and I have none,
I can’t hear the pump running in the boot with ignition on so I removed the white plug from top of tank to check voltage,
I’m only getting 0.5v with ignition turned on so I presume I should have 13v or so at this plug?

I am getting supply voltage at the fuel pump relay connections and I swapped the relay also to see if that helped but no joy,

Anyone got any ideas ?

Thanks
Malky

The pump will ONLY run for a few seconds when the ignition key is FIRST turned on and then ONLY when the engine is cranking or running!!!

You can JUMPER the relay (3 to 5 or 30 to 87) to get a continuous power to the pump and see if that helps.