Dave, By reading the existing diagram, The main relay and the aux relay are both activated by the key switch. At that point the power terminal terminal #30 is coming from the brown wires off the back of the alternator/solenoid/battery. Then when the relay's close the power is going to #1 fuse instead of coming from #1 Fuse. #1 from the diagram is feeding power to the ECU's via the green wire and other components. M:18:02 is a little mis leading because they aren't consistent in the electrical drawings of the position or power terminal input of the main & aux relay's. The ignition switch is only activating the main relay and the aux relay not carrying the current load. The 105 ( Start Inhibit ) relay is getting is however getting the power from the heavy brown wires from the alt to the ign switch to activate the starter solenoid. John Hervey -----Original Message----- From: Dave Swingle [mailto:swingle@xxxxxxxxxxx] Sent: Monday, February 09, 2004 12:10 PM To: dmcnews@xxxxxxxxxxxxxxx Subject: Re: [DML] Starter circuit theory? This is kind of a frankenstein car - the one I'm rebuilding from a burned car and a wreck. The entire electrical system - wiring harness and all, is out of the wrecked car, and I'm not really sure of the vintage of that one but I think its about 10/81. I think you are right - there is something "undocumented" in the wiring. At this point it's a non-issue but I would really like to understand it. I'll dive back into it with a voltmeter when I get a chance - an about a week. This also seems like the kind of thing where someone may have hacked the wiring to install a security system. [Moderator snip] To address comments privately to the moderating team, please address: moderators@xxxxxxxxxxx For more info on the list, tech articles, cars for sale see www.dmcnews.com To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnews Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/dmcnews/ <*> To unsubscribe from this group, send an email to: dmcnews-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/