no output from my 5 pin ecu

^^Easy. The path for coil current is key--through bulkhead---to ballast--to coil+ and through coil--and coil - goes back to the box and ground (Actual electron flow is opposite direction but I just mean "function"--describing the path.

So with the key "on" in "run" current flows through the coil. This means that coil voltage DROPS due to current through the ballast resistor, so check coil + reading---with key in "run" the coil should be around 6-8V or so, and NOT "same as battery"

If coil + is "same as battery" with key on, it means there is no current being drawn---which means either the box is not grounded, or the box is bad, or the box itself is not getting power--or the coil is open

Now measure coil- (NEG) It should read quite low, 1-2V which shows the box is "holding" the coil neg terminal "close to ground." If that terminal is 0, the coil is open or some issue no power to the coil. If it is same as battery, see paragraph above