If is all the pumps then look at the three connections to the main pump in the engine bay, could be a relay or just possibly a gunged up connection that needs a bit of contact cleaner, if not see if there is a blockage coming form the pump itself, they sometimes manage to get the odd leaf or dead bug in the system which can stop the screen cleaner from getting through.
Just an after thought, you do know that the front headlamp washers will only operate once the front window wipers have operated 5 swoops across the screen, you should then see a mist of spray coming from the front head lamp washers, took me ages to figure out until a 'wise man' on this site put me right. Hope this helps.
Here at LandyZone we have plenty of very knowledgable members so if you have any questions about your Land Rover or just want to connect with other Landy owners, you're in the right place.