Won’t start No Spark.
I’m new to the world of Mopar and also to MSD CDI systems. Are these boxes voltage specific meaning if they have low voltage they won’t work. Reason I ask. The battery was a little low from sitting all winter unattended. After trying to get it running. I had to run an errand with another vehicle meanwhile I had not removed the battery charger from the car. When I returned it started. Thank you for taking the time to reply. Eric.
I would certainly get the battery up. You can monitor battery voltage and crank the engine. If the battery is below about 10.5 when cranking I'd stop there and get it charged
Some background. First, if you don't have a factory manual, run over to MyMopar and download one, free
The MSD CD (6A or whatever) hooks up main power with large black ground and large red straight to battery. It is "triggered" on my a small red wire which goes to switched power.
Originally your Mopar ignition switch fed TWO separate power sources into the engine bay. IGN1 is "run" is powered ONLY when the key is in "run" and not "start." This goes DEAD in start
The other end of the ballast resistor connected to coil, and had two wires, one leading to coil, the other the "bypass" or IGN2 coming from the ign switch. THIS IS the only power to ignition during start. This wire comes alive when key is twisted to start, just like the yellow feeding to the start relay. BUT THEY are separate contacts in the switch.
So the (usually brown) IGN2 "bypass" and the (usually blue) IGN1 "run" need to be tied together to provide both start and run power. Access your ign and make sure it has power in both key positions.
