hi ed

a fellow ed here

I had the same problem on my 86 cab.Have you got the original jag aerial? The previous owner of mine had fitted a new mast but had left the base of the old mast in it and the aerial never reached the bottom of the mechanism. This meant that it never switched off and it slaughtered the battery. As soon as I fixed it the problem went away. Hope you find the problem soon

cheers

Eddie Panton