#1 coil is always grounded, burning fuse (Ford coils), all other coils don't get signal.

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DreamV4

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Other coils don't burn fuse.
Seller said harness problem, he gave me second harness.
I believe he was saying something about generator electrical parts.
Here is possible reason( just an idea)
One of pick-up coils is shorted, giving signal to ign. module to ground 1st coil.
Fuse doesn't burn until connector is attached to 1st coil.
Maybe just shorted wire between coil and ign. module.
I have until morning to come up with diagnostic plan.
any ideas?
 
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Fire-medic

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You have the 'late-model' ignition, only one pick-up coil. Sometimes it gets an intermittent open-circuit, and the engine quits. Let it cool-down, and it will start again. Other times it will not pass the resistance test. Then, it will-not start.

If you have a charging/lighting circuit in the stator bad, that's another test.

VMax electrical resistance data enlarged.png
VMax primary coil-pick-up coil resistance.png VMax Stator ohms reading.png
 

DreamV4

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Great, thanks!!! that is important!!! only 1 coil!!!!!!!
It makes sense! Bad pick up coil will drive ign. module crazy and module will not "know" that crank is turning. Pick up coil works kind of like crank sensor.
electr pick up.jpg
 
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DreamV4

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Moderators, please move to 1 gen. sorry...
 

02GF74

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The pick coil or coil(s) give a signal to the ignition unit so that it can determine when to produce the spark.

If the power line to one of the coils is always grounded, then I don't see how the pick coil can be responsible. If the pick up was faulty it would affect all the power lines to the ignition coils.

Disconnect the leads to the coil and ignition module and measure resistance between power to coil and ground to see if there is a short

I suspect the ignition module's output stage the coil is damaged.

I think you are using COPs - you've checked the ignition coil is not faulty easy to swap it for another.
 

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