Thats better
After diconnecting the relay I could see that water had been getting in from the white crud around the contacts (picture 2).
I cleaned up the terminals with wet and dry. Then put the relay back together using a thin smear of Blue Hylomar on the edge of the mating face and left it a while to 'go off'. Then I wraped some insulating tape round the joint for good measure and reassembled.
Remember to connect the positive cable to the battery first.
I will let you know if the problem is fixed. Please let me know if I have cocked up on any of this
