No ground on entire ignition system

[Entity]

So, long story short, my girlfriend's Ranger won't start. Ironically, the last time it started was when I tested the fuel pressure, which is good. It will hold pressure in the fuel system fine, so I had the entire ignition system tested. Not a single component leading clear back to the PCM has ground, but has power to it. I put a new PCM in to rule that out, and it still has no spark. The relay is clicking on fine, and I switched it out to be sure. Aside from torching it and dancing around the flames, I can't think of where to go next. Anyone with an idea, please send it my way! Thanks, all.

 

[Rearanger]

so I had the entire ignition system tested.

By whom?

Not a single component leading clear back to the PCM has ground, but has power to it.

Did you test the PCM ground connection? Do other components work - lights, radio, horn, etc.?

 

[Entity]

I apologize for my delay in responding... in the middle of a hectic move. I had it tested by a mechanic (20+ years experience) friend of mine. Didn't test any grounds from the PCM because, frankly, I wasn't sure where that'd be. Every other accessory works, just not the ignition system. Horn, radio, lights, etc.

 

[Rearanger]

Creating spark is done by grounding and ungrounding the 12v primary of the coil(s). The PCM switches this grounding on/off with inputs from crank sensor, etc. If there is no path to ground then the switching won't occur. You'll need a circuit diagram to locate PCM ground to test or use a jump wire to establish.

If you can locate the 12v primary lead to the coil(s) then you should be able to hook a test light to it to see the switching as you crank the engine.