Help Please...electrical/starter Fault With My E34 524td
Hope someone can give a bit of quick advise here, i recently bought a 524td (1991) it has developed an irritating fault in starting, for some time it occasionally is effectively dead when turing the key (starter does not engage, though fans, lights etc come on) after a couple of attempts it starts, however the other night i tried to start it and it sounded like the battery was drained, sluggisg starter motor etc, i swapped the battery with another car i have and it started first time, however after being left for 15-20 minuted plus it was dead again this time nothing, no starter, dash warning lights, nothing!...however i discond the battery terminals, reconnected and it again started first time, so i cant undertand why discon and recon of battery would kick things back in? starter or starter solinoid perhaps, and how do i know if its one or the other?
Any help greatly appreciated!!