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No power to DME pin 18 in 86 325 es.

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    No power to DME pin 18 in 86 325 es.

    Hello folks, 1st time E30 poster, long time E24 owner. Helping a friend with typical no start, no spark condition on 86 325 es Motronic 1.0.

    One day he went to start and it cranks only. I've check everything as found here, E28 forums, Bimmerforums, Bimmerfest but nothing similar to final diagnosis: no sparks, no power to pin 18 in plug, main relay is hot with no key in.

    I followed these with result below : , ,

    I checked CPS at plug and pin 25 and 26, then 27 and 8 at Dme plug: 1000 ohm. Checked fuel pump, relay and injector by jump pin 30 and 87 at both relay, jump DME pin 20 to 19 or ground for FP and DME pin 14 and 15 to ground for injector pulsing. Went through every component 3-4 times.Coil is new and tested.

    What I can't figure out is: DME pin 18 ohm out to pin 30 so wire is not broken to main relay socket BUT no 12v to pin 18? Main and FP relay works/ click and relay socket 87a has 12 V but I can't find out how main relay power from socket 87a to 87 or 30? DME don't have power from pin 18 so DME not turn on? Main relay constant on and HOT even with ignition off? Any suggestions? TIA.