Raggedroy
VIP Member
Cool, if only there was a diagram for the T5.1.It looks to me from the current flow diagram as thought the simple solution is to remove fuse SB23 from the fuse panel. This would appear to be the feed from ignition sw to starter. Without the fuse it won't start.
http://www.1946vw.co.uk/vwbooks/vw_info/T5_pdfs/T5_Basic_Elec_ 2005-7.pdf
Page 2. D is the ignition sw, B is the starter. The last twist of the key (the spring loaded part) will send juice to the starter motor via fuse SB23. Remove the fuse, it won't start.