Hard to say what that terminal plug is. Close to the master cylinder, not part of the HP fuel pump?
Battery is ok? Fuses all good? Ground wire connections corroded?
Even if you do re-connect that plug, were there any other signs or conditions about it not starting? I wonder how.. that plug became disconnected in the first place? Any work done on the engine by yourself or others lately?
Hang in there someone here will have an answer for you. John or TS or Robo will know the electrical stuff for our cars. I'll see if can find a parts drawing on the engine bay, might give a clue to what it does, concerning the starting system, if that's it?
Last edited by LAC Sky; 01-08-2019 at 06:40 PM.