Voltage drop at ballast resistor

Ninety percent of the time you do NOT 'really' have a 5 pin ECU and therefore the 4 pin resistor is only "using" the coil side of the resistance. This is easily confirmed with the following test:

Turn key to "run" engine off. Ground your meter, and determine where the switch side of the resistor is. These are the two poles jumpered together, if you cannot see that they are the two terminals with the highest voltage reading

Now read one of the other two. One will be same as coil + because that is where it's connected. If it reads 6-9V that is "fairly normal"

If the 4th terminal reads "same as" the switch terminals, that is the ECU terminal and that shows there is NO CURRENT in other words the ECU is not drawing that terminal. In other words, nothing is connected to it.

Further, the old "points coil" resistor is wired to the coil in exactly the same way on electronic systems. If the ECU quits, or distributor, and the coil/ resistor/ wiring is OK, you can unplug the ECU, drop in a "points" distributor, hook the dist. wire to the coil NEG and go down the road