Once you bypass the Pump relay (30-87 jumper) you remove all control automation on the fuel pump, so if it does not run after bypassing, the culprit is not the DME relay or Pump relay, or the DME itself. The only remaining components are the fuse F23 and the pump itself, besides wiring. It is not usual to find wire issues, contact issues may be, but not wire issues. Overheated contacts in fuse, relay, connector sockets and ground connections may lead to high resistance current paths dropping the available voltage to values below operative requirements, but you would notice through visual inspection such damages. I have not seen this damages in the fuel pump circuit, but I do have seen fooling fuses (visual inspection of the filament presence is not enough to check a fuse Ok).
Regarding your interest in locating the grounding point for the pump (Terminal 4), I'd suggest you to download from Shogun's web site http://twrite.org/shogunnew/topmenu.html => Reference Data => wiring diagrams => wiring diagram others => E34 directory of files => e34_93.pdf (Bookmark Shogun's web site, it is plenty of resources).
In the downloaded pdf look after page 7100.0-02, figure 2 and identify location of X495 underside the rear seat Right hand side.
Page 1210.13-02 shows the Fuel pump circuit, note that B tag leads to B+ post.
Reply With Quote