In a Mopar electronic ignition, battery + voltage goes thru bulkhead connector to ignition key switch. From the ignition switch, out thru bulkhead connector to ECU (orange box) and to the resistor. (it also goes to alternators voltage regulator on the bat terminal) The resistor is in series with the coil only in the RUN condition. The ignition switch electrically bypasses the resistor when cranking in START position, to provide full battery voltage to the coil for a hotter spark for getting engine started. With the ignition switch In the RUN position, the resistor is electrically in series with the coil circuit and coil voltage is reduced and current is limited by the resistor. The one side of the resistor goes to one terminal of the coil the other terminal of the coil goes to orange box connector.
In the most basic terms, the ECU or orange box electronically completes the circuit from one side of the coil to ground, replicating a light switch opening and closing on-off. Or, like the points in the distributor would in a car without electronic ignition. The pickup coil in the distributor sends a small magnetically generated "trigger" pulse to the ECU, in the ECU this pulse will eventually turn on / off a transistor ( the large one on front of ECU) to complete or interrupt the circuit the coil. This transistor is what is actually doing the switching on and off, of the voltage to the coil. This is why it's so important that orange box has a good ground.
Anything mentioned above can be having an effect on spark. The cars ignition switch, ECU, coil, resistor and bulkhead terminals are all at play to make the ignition work. Anything from coil to distributor and plugs is all on the output side of the coil and Hi voltage. Schematics are helpful.