My Names Zach, I own a 1974 dodge Powerwagon.. I have located a box on my fire wall that connects to both bottom on top of the ballast resistor.. This box looks somewhat like a voltage regulator but is not at all. It has a inline three prong connector. This box has H8D fairly Large on it, With a Chrysler Stamp. It also has two part numbers on it
375 A and below that
3874129


I need help figuring out what this is...
My truck is Currently not running,, I have tested all the Electrical, and everything passes.. And I still have no spark. This Box runs connects to the ballast on both top and bottom connectors, Could it be that this box is preventing a circulating current for the ignition coil to function properly?

 

Your part is an emissions control switch.

You've obvioulsy missed something.

Your ignition system has very few components, all of which are easily tested with a DVOM.Assuming you have power to the coil (Key on/start power is there, ballast OK), your problem is with one of the following components or wiring between them:

-Distributor pick-up coil(s)

-4/5-pin ECU

-ignition coil

These systems are somewhat prone to failure, but you can replace every component in the secondary system for under $200, so it's really not a big deal. I keep a spare of every ignition part in the trunk of my '78 Aspen, along with an alternator, belts, hoses and other sundries. Barring engine/tranny/diff failure, there is nothing I can't fix on the side of the road.

 

Well after further working on my truck, I have replaced the Distributor, and the Brain Box, ECU, and the Coil.., There is power at the coil, and at the 3 of the 5 pin ECU.

The Two Prong wires coming off the distributor, what are they supposed to read at on a meter?

 

Own a Dodge Ram Van 1500 automatic v8 5.2 liter. Have all towing equipment to go behind a Class A RV for flat towing. What do i get so I do not have to disconnect drive shaft when towing flat . Thanks