If you see all those problems and your battery was checked and its good than you have a alternator problem and is time to fix or replace your alternator. Bmw e39 alternator wiring. Rdl posted today some nice charging circuit & starter wiring diagrams for the e39 in yet another ubiquitous car-won't-start thread today i reproduce his information below in the hopes that someone whose car won't start, in the future, who has determined it's not the battery, nor the alternator, nor parasitic drain, that it might be the starter circuit.
bmw e39 alternator wiring
Some people have heard that on “old” bmws with a four-wire alternator and an external voltage regulator—meaning 2002, bavaria, and e9-era cars—as well as on cars with a two-wire alternator—meaning, mostly, pre-1996 cars—if the alternator light is burned out, the alternator won’t work because it’s wired in series with the light. 2001 e39 m5 : silverstone blue, 19" breyton spirits (horribly rashed...genuine bbs lm's to go on), philips silverline indicator bulbs, intravee ii and alpine kca-420i (in a box in the house) and 160gb ipod classic , evolve headers and race cats to go on, otherwise standard at the mo... lovelove "i look at it like this.. I have a 2003 bmw 525i e39. brand new bosch oem alternator tested, brand new h8 battery tested, battery light on the dash is on all the time. fuse 15, 18, 38 checked, all ground connections checked, red wire 30 b+ in the back of the alternator indicates the battery voltage..
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