1985 Spider Graduate-No Spark

["aitken.ssr" <aitken.ssr@domain.elided>]

The engine cranks fine but there's no spark. I tested the ignition ECU
harness and found that terminals 5 & 19 that are supposed to go to ground
(earth) in fact don't!  Does anyone know if these two go to a common ground
and where it might be found?
Thanks for you help!

Jim Aitken
Charlottesville VA

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