Moparts Tech Archive

ECU wiring diagram

Go to your auto or elec supply store and pick up some of the connectors in the pic below.

Now go to the tech area and look at the ballast resistor thread. It has this picture in it.

Now on the car unhook both ends of the old ballast res. and remove the old one and replace it with the one in the kit. "hook NO wires to it yet"

Then turn the key to the run position and take a meter or test light and find which one of the 2 connections (wires that plugged to the ballast) has 12 volts on it and mark it ign #1. The other wire shouldn't have power to it.

Then have someone hold the key in the start position of the switch, and check the other wire to the ballast, it will have 12 volts on it then this is the ign #2 side. Not really a need to do it but it's a way to check yourself, and make sure you have id'ed the run side of the ballast.      Mark each wire to the ballast ign #1 or ign #2, It will make it easier to id them later.

Take the brass piggy back connector and put it on one end of the ballast. Then take the female wire connector and put it on the end of the Blue wire from the ecu box, and connect it to the brass piggy back connector.

Then take the wire from the key switch ign #1 (the one with 12 volts when the key was in the run pos) and hook it to the other spade on the piggy back connector.

Connection is complete with that wire.

Then run the black wire from the ecu box to the neg (-) side of the coil and then that connection is complete.

Rehook the other side of the ballast res(start or ign 2 in the ballast pic) back up.

Make sure the ecu box is grounded and the dist is plugged up. We run a wire from one of the bolts we use to bolt down the ecu box back to the neg (-)battery post to make sure we have a good ground.

The final connections to the new ballast will be like in the pics below.

You can swap the ign #1 wire and the blue wire from the ecu on the brass piggy back if you want to or need to. Sometimes the female connector on the org wiring harness will fit better on the top spade of the brass piggy back connector.

And now you can start the car.

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