I have an 82 aircooled CA Westy,

My van used to run fine, a stumbling at light load turned into it not starting any more.

This is the only malfunction I can find in the system is...

I have =battery voltage(12v) at the + injector connector(to ground) on the wiring harness, key on,
but no signal (using LED voltage tester) when turning engine over(connector + to connector ground at ECU using test light).

I have continuity on; each wire in the harness& all three grounds on the ECU.
I have voltage to the ECU

I'm assuming it's the ECU and am in the process of getting it replaced.

THE QUESTION IS...

Is there any other component, or combination of components that gives the ECU the signal when to fire the injector??? That may be the culprit for not getting a signal at the injector?