Starter clicks using the key, engine starts by jumpering the relay

Dana67Dart said
You may have already figured this out but.

When you use a screwdriver between the battery terminal and the Sol terminal (red) you are bypassing the starter relay and not testing the starter relay for functionality.

When you jumper from the batt terminal to the I (Ignition, IGN 2 whatever you want to call it) terminal (Green) you are bypassing the ignition switch but testing the starter relay for functionality.

View attachment 1716072241

As to why it will start when the turn signal is on, I would assume you or someone has removed wires from the steering column connectors and put them back incorrectly.

That makes sense now, thank you.

Phreakish said
I've noticed when the second small ground wire from my battery to the core support on my 72 is disconnected, and on my 83 pickup, I get strange behavior like that involves the turn signals.

I think you said the big negative to the block is fine and clean. What about that smaller one that usually grounds near the radiator?

I had a dead short caused by my clutch linkage which melted that wire at one point and I played hell finding it because it's not very long and isn't in a place my eyes land often when looking around under the hood..

Just a thought in case it helps.

It's funny you mention that small ground wire, because ever since I bought the car, I noticed that small ground was cut right at the post, so that ground is nonexistent. I'll fix that next time I'm under the hood.