so i dismantled the the vacuum pump in the boot and it was all in good condition no sign of any water having ever been in there and the circuit board and all associated connections were free from any corrosion.

Are there any other tests i can do to try to figure out what is at the root of this?

What does rf reciver do with the info once the key is pressed? Im assuming it sends a message to the body control module? if so is there anyway to test if it is recieving the info? or sending a message to the door lock pump?

sorry for all the questions but i have driven landrovers for the last 10 yrs