Mopar electronic ignition wiring schematic question

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prorac1

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The above picture is what we are using for electronic ignition, and dual field alternator and regulator conversion . Two post ballast resistor, and four pin ECU.

My question is, there are three unlabeled wires that go off towards the right-hand side of the schematic.

One of them, obviously is the main charge wire for the alternator.

What are the other two?

The original wires for the point style ballast resistor?

Thank you in advance for the help. Eric and Jason.
 
Believe ballast goes to key switch.

I believe your right. I believe that's what those wires are.

A keyed hot and a crank hot.

Original ballast wires.

But I'm not sure if they are polarity sensitive, or if they are even ignition switch wires honestly.

Assuming gets me in trouble. Lol.
 
Yep I just put my pos away for winter storage. Electrical issues fd my entire summer up. Sorry I ain't much help lol. Good luck.
I believe your right. I believe that's what those wires are.

A keyed hot and a crank hot.

Original ballast wires.

But I'm not sure if they are polarity sensitive, or if they are even ignition switch wires honestly.

Assuming gets me in trouble. Lol.
 
Yep I just put my pos away for winter storage. Electrical issues fd my entire summer up. Sorry I ain't much help lol. Good luck.

Thank you for trying though. LOL.

That's why were over analyzing every circuit on this wiring harness. To avoid having those problems in the future. It's all laid on the bench in front of us, if we're going to do it, we may as well do it now and right.
 
I don’t understand the diagram. Why is the voltage regulator hooked to the start ignition supply? Seems wrong to me. Seems like the blue voltage regulator wire should be on the other side of the ballast resistor.
 
Top wire appears to be “start”
Middle wire appears to be “run”
Bottom wire appears to be “battery”
 
I don’t understand the diagram. Why is the voltage regulator hooked to the start ignition supply? Seems wrong to me. Seems like the blue voltage regulator wire should be on the other side of the ballast resistor.

Beats me. But that's how all of the diagrams I'm finding are wired.
 
IMG_4787.PNG


I found this Schematic from Mopar performance. It seems more along the lines of the one shown above only with a two post ballast resistor
 
View attachment 1715251082


The above picture is what we are using for electronic ignition, and dual field alternator and regulator conversion . Two post ballast resistor, and four pin ECU.

My question is, there are three unlabeled wires that go off towards the right-hand side of the schematic.

One of them, obviously is the main charge wire for the alternator.

What are the other two?

The original wires for the point style ballast resistor?

Thank you in advance for the help. Eric and Jason.

That diagram is wrong. The coil/ ballast wiring, whether 4 or 2 wire is unchanged from points. That is, the coil part of the wiring is all the same.
 
That diagram is wrong. The coil/ ballast wiring, whether 4 or 2 wire is unchanged from points. That is, the coil part of the wiring is all the same.

So the ballast is wired backwards in the original pic I posted?

Should I use Pishtas diagram than?

Thanks. Eric
 
https://www.forabodiesonly.com/mopar/attachments/img_4787-png.1715251248/[/mg]

This is also partially wrong because of the reference to the yellow colored wire to the start relay. That wire is also unchanged in reality. It is supposed to be the coil/ bypass circuit IE ign2, which goes from the coil+ side of the ballast to the ignition switch IGN2 contact. it supplies power to the coil/ ignition for starting and bypasses the ballast

If you are ADDING a 4 pin ECU / breakerless system here are the basics Numbers are simply enumerators not pin numbers

A...GROUND ECU box MUST be grounded. MUST
B&C..........distributor pickup
D...............power to ECU. This goes to the "high" side of the ballst, IE directly from the key IGN1. This point also branches off under the hood and supples alternator field (blue), VR IGN terminal (blue) electric choke if used, and sometimes smog devices
E...........Coil NEG........this wire goes to coil - and switches the coil on/off just like the points did
 
This is from MyMOpar. It is correct except it does not show the bypass (IGN2) circuit which is unchanged, anyhow. Notice at top right it says "splice" and "new wire". This is spliced into the existing ballast power supply wire from the key. So basically you leave the ballast / coil alone, disconnect the points, and hook the wire from the ECU up to the coil NEG in it's place

Ignition_System_4pin.jpg
 
Sorry guys but some of the diagrams posted here are too darn small for me to read
 
https://www.forabodiesonly.com/mopar/attachments/img_4787-png.1715251248/[/mg]

This is also partially wrong because of the reference to the yellow colored wire to the start relay. That wire is also unchanged in reality. It is supposed to be the coil/ bypass circuit IE ign2, which goes from the coil+ side of the ballast to the ignition switch IGN2 contact. it supplies power to the coil/ ignition for starting and bypasses the ballast

If you are ADDING a 4 pin ECU / breakerless system here are the basics Numbers are simply enumerators not pin numbers

A...GROUND ECU box MUST be grounded. MUST
B&C..........distributor pickup
D...............power to ECU. This goes to the "high" side of the ballst, IE directly from the key IGN1. This point also branches off under the hood and supples alternator field (blue), VR IGN terminal (blue) electric choke if used, and sometimes smog devices
E...........Coil NEG........this wire goes to coil - and switches the coil on/off just like the points did

Thank you so much. That definitely cleared a lot of things up.

I think I was over thinking it.

Leave ballast wires alone (stock)

Tie dual field alternator/regulator in with 12 volt feed to ECU.
 
This is from MyMOpar. It is correct except it does not show the bypass (IGN2) circuit which is unchanged, anyhow. Notice at top right it says "splice" and "new wire". This is spliced into the existing ballast power supply wire from the key. So basically you leave the ballast / coil alone, disconnect the points, and hook the wire from the ECU up to the coil NEG in it's place

View attachment 1715251276

Our biggest stumbling block is that we are starting with an empty shell.

So I had no previous hook ups to reference from.

IMG_4742.JPG
IMG_4773.PNG
 
This is from MyMOpar. It is correct except it does not show the bypass (IGN2) circuit which is unchanged, anyhow. Notice at top right it says "splice" and "new wire". This is spliced into the existing ballast power supply wire from the key. So basically you leave the ballast / coil alone, disconnect the points, and hook the wire from the ECU up to the coil NEG in it's place

View attachment 1715251276


Maybe a silly question.

But (just in case, I'd better ask) can you plug the two ballast resistor connectors in on the wrong ends?

As in mix the two single spades side for side and still work the same?
 
the dual resistor has 2 resistor values (5 ohm feeds ECU, and .5-1.5 ohm to feed the coil) , but they are not polarized, hook em in any direction you want. Here is an old quote, take it or leave it:

"...Ok... let's clear up

dual ballast provides two sources by two diff resistances. One is 5 ohms ( secondary ) which feeds the stock 5 pins ECU, and the other one is anything between 1.5 or .5 ohms ( Primary ) which feeds the coil.

single ballast just provides power for the coil. Resistance varies depending on which one and application, between 1.5 and .25 ohms

on 5 pins ECU, the 5th pin takes ONE POWER SOURCE from the secondary ballast resistor on dual piece.

on 4 pins ECU, the secondary resistor is not anymore outside, was moved to INSIDE the ECU... that's why the pin is gone

you can fit a 4 pins ECU on an stock 5 pins system without problem, simply the secondary resistance power will be going to, ANYWHERE... the pin is not there

you should NOT use the 5 pins ECU, on a system set to 4 pins. Probably your car will start up and ride around, what doesn't mean will work properly..."

confirmed...
mopar_5pin_ign.jpg
 
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Wiring has begun.

Thank you to everyone for the help. I have a much better understanding of the chrysler starting and charging circuits and how they intermingle with the ignition system. Thank you again.

Come to find out……we have a 5 pin ECU. In the pictures I was looking at the center screw blocked the 5th post.

Not a big deal, we had a brand new 4 bin ballast on hand.

We also bypassed the bulkhead with the main hot wires, cleaned all connections and terminals with evaporust, wired the alternator charge wire to the starter relay, and ran new heavier guage wires to the interior, the battery (to feed the relay), and from the starter solenoid to the starter relay.

We added in the electronic ignition, square back dual field alternator, and electronic regulator as well.

So far it's turning out great.

As the pictures show we are slowly "looming" everything together in an organized fashion.

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^^I doubt you have a 5 pin ECU. You cannot tell by looking. Many especially aftermarket (that is one) ECU have 5 PHYSICAL pins but the 5th is unconnected. Without ohms test to the rest of the pins you cannot tell. But that is a "newer looking aftermarket" and I'd bet it is a 4. Running a 4 pin ballast won't hurt, it simply doesn't use the other section

How to tell for sure? Easy. After you get it all wired up and running. Measure all 4 pins with the engine running. The two which are jumpered together will measure "same as battery" that is whatever the running V is (13.8--14.2) If the other two are both used, they will measure somewhat LESS than that showing that current is dropping voltage through them. If one is unused, it will be same as the supply pins
 
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