Am I getting this?

More spark issues, I previously had the ballast resistor wired all kinds of wrong, with power going into both ends of the ballast (don't ask, I don't know lol), wired it up correctly this time, except that the coils power supply is resisted during cranking and running (keyed hot is manually switched and doesn't lose power when key turns to crank... regardless, back when the wiring was all messed up, the coil would spark decent but only once per second, and the plug wires barely sparked at all, now on new setup the coil doesn't spark at all. Just want to make sure that I understand how the electronic system works: box gets full 12v, box gives pickup coil power, pickup coil tells coil when to fire, coil tells plugs wires when to fire, plugs fire in given sequence/timing, correct? Trying to troubleshoot but don't know where to start and really need to learn this system instead of posting threads on here every other day, big TIA

Watch these You Tube videos. In the first one the way the coil is wired is not accurate to your system but close enough. (the positive side of the coil gets power directly from the blast resister rather than the control box as in the video)

The second one is not an electronic ignition but you could set the same thing up on a bench to test your components. make sure everything that is typically grounded to the car body is all tied together and to batt negative.

check this website out it should help

Dave's Place - Chrysler Electronic Ignition System Test[/UR

Troubleshooting
Troubleshooting an electronic ignition system is fairly simple. Once it has been determined that there is no spark, there are a few quick checks that can be performed to determine the cause. A DC volt/ohm meter can be used to check the continuity of the pick-up coil. It can be checked at the leads as they leave the distributor, or on pins 4 and 5 of the ECU connector. When measuring the resistance across the two leads of the pick-up coil you should see a 150-900 ohm reading. Always flex the wiring leading to the distributor and to the ECU while checking the resistance to be sure that there are no breaks in the wiring. You should also check for 12 volts at pin 1 of the ECU connector when the ignition is in the "on" position. It is also important that the ECU be securely bolted in place and that bolts provide a good ground to the ECU housing. The only other lead that is connected to the ECU is the "-" lead to the coil, which can be checked to insure that it is not broken.



Chrysler Electronic Ignition

The other important component of the electronic ignition system is the ballast resistor. It should be checked with an ohm meter and should have 1.2 ohms of resistance. Typically, a failure of the ballast resistor will result in the engine starting, but then dying as soon as the key is released from the start position. It is often handy to have a spare ballast resistor or ECU lying around to use for troubleshooting.

Check your wiring against this

I'm no expert on ignition, but not a newbie on electronics either.. I have gotten a much better understanding of how electronic ignition works over the last week or so while working through some electrical gremlins of my own. So I wrote my understanding of it in my build thread. Maybe it will help.

BigBlockMopar28 said:

More spark issues, I previously had the ballast resistor wired all kinds of wrong, with power going into both ends of the ballast (don't ask, I don't know lol), wired it up correctly this time, except that the coils power supply is resisted during cranking and running (keyed hot is manually switched and doesn't lose power when key turns to crank... regardless, back when the wiring was all messed up, the coil would spark decent but only once per second, and the plug wires barely sparked at all, now on new setup the coil doesn't spark at all. Just want to make sure that I understand how the electronic system works: box gets full 12v, box gives pickup coil power, pickup coil tells coil when to fire, coil tells plugs wires when to fire, plugs fire in given sequence/timing, correct? Trying to troubleshoot but don't know where to start and really need to learn this system instead of posting threads on here every other day, big TIA

Click to expand...

FYI
The pick-up coil is a signal generator. There is no power going out to it. When a reluctor vane swings by it, it generates a very tiny signal, and sends that to the ECU, which interprets it.
The coil is a transformer. It has about a step-up ratio of about 12 to 24000 or more. It generates a secondary voltage when the primary side magnetic field collapses.
The Ecu is just a glorified switcher.When the ECU receives a signal from the Pick-up, it opens the coil ground. This collapses the magnetic field in the coil primary, and the secondary immediately responds by sending out a armada of electrons which find their way to ground......hopefully at the plug-tip.
The ballast-resistor is just voltage reducer. As it heats up, it will cut battery voltage to about 60%. This helps the coil generate maximum secondary voltage for starting a cold engine.
Depending on the type of ECU, it might also require a voltage reduced power supply. The 5-pin ECUs are this type and require a dual-ballast resistor. This is just a fancy name for a ceramic block with two resistors in it. The 4-pin ECUs do not require a stepped down power supply. The 4-pin type plugs directly into a 5-pin harness with no changes; the output from the second ballast is just dead-ended at the Ecu.The 4-pin Ecu gets it's continuous power supply from a different pin.
Hope that helps.
BTW
the pick-up coil circuit is polarity sensitive. If you reverse the polarity on the pick-up coil, the ECU will get lost as the rpm increases. So the pick-ups are color-coded for the engine they will run on. SBM distributors spin CW as viewed from the top, and one of the wires (OEM) is usually orange.The second one I forget....
TIPS
The pick-up coil works better the faster the iron reluctor vane swings by it.
The gap seems to be OK from zero to .030, but the spec is .008 to .011
The ECU must to be grounded back to the battery, via the mounting surface and the body grounds; one at the back of the passenger side of the head to the firewall, and then most important,from the core support to the battery.

Here is a quick-test for the coil
Remove all wires from the coil negative, and near-ground the hi-voltage coil wire. Grab the longest coarsest file you have and lay it on a grounded surface. Find a small gauge (10 to 16) wire long enough to span from the coil to the file and attach one end to the coil neg. Strip and Isolate the other end from ground. Now go turn the key to on. Return to the wire. Pick it up about 4 to six inches from the end, and stroke it along the file, lifting it before you run out of file-teeth.( Do not leave the bare end sitting on the file; this will eventually overheat the coil.) As you are doing this, watch for a stream of sparks issuing from the near-grounded coil-wire. If you got it, then the coil and the run circuit are working fine.
Then test the crank circuit the same way, but it's a good idea to disable the starter. I do this by just putting the gear selector into any gear except Neutral or Park. And you will need a helper to twist the key. If you again get the spark stream, then the cranking circuit is also fine.
But if either of these fails to make sparks,the first thing to do is to run a 12volt jumper from the battery directly to the coil plus, and retest. If this also fails then replace the coil.
But if this gets you the sparks, then attach an analog voltmeter to the coil plus and to ground. Then retest, taking note of the rest voltage, and voltage-drop as you are stroking the file.
Next, remove the 12v jumper.Then turn the key on. Note the voltage compared to the jumper.If the ballast is cold, the voltage should be very similar. If it's not, then turn the key off and bypass the ballast. Then turn the key back on, and again note the voltage, then begin stroking the file, and watching the meter and listening for the spark-stream. The rest-voltage and voltage-drop should be the same as/very similar to, when you jumpered the coil-plus. And a stream now indicates bad ballast. But still no stream, or a plummeting voltage-drop, indicates a problem in the power supply.
This begins the hunt; start at the fusible link. Give that link a good pull; maybe it has only a strand or two still passing juice,which is enough to measure voltage, but it's a total bottleneck to actually passing electrons. Don't wuss out on the tugging.
If that's good, move to the large gauge red and black wires in the bulkhead connector, Next, disconnect the battery, then move to the amp gauge, making sure the wires are tight on the back of it. Spend some time on this guy, as he is known to be a trouble spot.
Next is the ignition switch itself, but I almost never have to go that far.
As to the ammeter
inside the ammeter is a big bar that bypasses most of the electricity, but a shunt is taken off it to drive the needle in direct proportion to what is flowing in the main bus-bar. The studs coming out of the back of the gauge are directly attached to that bus-bar................or are supposed to be. As I recall they are just swedged to the bar so an overzealous mechanic somewhere in the distant past could have broken or loosened the swedge, and over time the electrical load might have burned it off internally.......but the shunt still exists, so some current can/might still pass thru that; and nobody is the wiser. So you have to pay particular attention to this guy. If you find that something like this is what has happened to your ammeter, you can do one of three things; 1) replace it, 2) bypass it, 3) repair it.
To bypass it just put both wires on the same stud and secure the nut.
To repair it; fabricate a new copper bus bar and strap it across the studs. You have no accurate way to determine the size of the bus, and that will affect the gauge reading, but if you are close, you might be back in action ;at least long enough to procure a replacement.
Now for the most important part. Once that exposed copper bus bar is on there, you have to make sure nothing can ever short across it to ground. So do what you gotta do to prevent that.........and then you can reconnect the battery.
I don't want to read about your car being burned down to the ground. Well actually that would probably never happen, cuz the fusible link is supposed to prevent such things; I just wanted to scare you a little bit to make you aware of the possibility,lol. What I'm saying is don't fudge the F-link!

BigBlockMopar28 said:

1. box gets full 12v
2. pickup coil tells coil when to fire
3. coil tells plugs wires when to fire
4. plugs fire in given sequence/timing

Click to expand...

Step 0 is to describe your vehicle. Everyone is assuming a 1971+ A-body w/ factory electronic ignition.
1. "box" = Mopar ECU? What color (it matters)?
2. no, pickup tells ECU when to fire. The ECU transistor stops the current flow to ground thru the coil primary wire when it gets a trigger signal. When not triggered, the current flows - charging up the coil for the next spark.
3. no, the coil is not a sensor, it is a driver and forces current to flow thru the HV leads. It builds whatever voltage is necessary to jump the spark gap (or short thru the wire).
4. yes, the distributor distributes the spark to the correct spark wire. It is turned by the camshaft and adjusted to match the valve openings.

BillGrissom said:

Step 0 is to describe your vehicle. Everyone is assuming a 1971+ A-body w/ factory electronic ignition.
1. "box" = Mopar ECU? What color (it matters)?
2. no, pickup tells ECU when to fire. The ECU transistor stops the current flow to ground thru the coil primary wire when it gets a trigger signal. When not triggered, the current flows - charging up the coil for the next spark.
3. no, the coil is not a sensor, it is a driver and forces current to flow thru the HV leads. It builds whatever voltage is necessary to jump the spark gap (or short thru the wire).
4. yes, the distributor distributes the spark to the correct spark wire. It is turned by the camshaft and adjusted to match the valve openings.

Click to expand...

Particular vehicle is a former lean burn 1st gen ram, converting it back to the old style electronic ignition. The ecu itself is a 4 pin parts house box, blue if it matters, not an orange box or anything of that nature.

BillGrissom said:

Step 0 is to describe your vehicle. Everyone is assuming a 1971+ A-body w/ factory electronic ignition.
1. "box" = Mopar ECU? What color (it matters)?
2. no, pickup tells ECU when to fire. The ECU transistor stops the current flow to ground thru the coil primary wire when it gets a trigger signal. When not triggered, the current flows - charging up the coil for the next spark.
3. no, the coil is not a sensor, it is a driver and forces current to flow thru the HV leads. It builds whatever voltage is necessary to jump the spark gap (or short thru the wire).
4. yes, the distributor distributes the spark to the correct spark wire. It is turned by the camshaft and adjusted to match the valve openings.

Click to expand...

READ the above!!

Here's a post I made about the simplest way I know to get across testing the ECU/ ignition parts

You need a coil, the ECU and the distributor

Lay it out on the bench. Follow the diagram. Find the two distributor pickup terminals on the ECU. Hook them to the distributor

Hook the ECU case to battery NEG

Coil does NOT need grounded

Distributor does NOT need grounded.

Hook coil + to the power lead terminal on the ECU. Get a clip lead hooked there and let dangle. This is your battery "hot" when you are ready

Hook something from coil "case" to a probe for testing spark.

Hook up your power clip lead. Twist the distributor shaft while holding the test probe near the coil tower. The thing should make sparks

If not, unhook distributor. Take first one, then the other pickup clip leads, and "tap tap" ground them at the battery connection. Coil should make 1 spark each time you do so.

If not, try another coil. If that does not fix it replace the ECU

IF you hook it all up and it WORKS, then there is something AFU in the car harness. SUSPECT a bad ECU connector OR a bad DISTRIBUTOR connector
=============================================
This is all you need to test the basics of the ignition. You can easily test the ballast separate. A battery, the ECU, distributor and a coil, and of course some test leads

View attachment 1715095428

Below, the basic diagram for a 4 pin ECU

View attachment 1715095429

Below, the wire for testing spark. I use my 12V test light. No, LOL the spark won't blow up the bulb

View attachment 1715095430

Below, the ground connection. ALL you need is one wire from batt NEG to the ECU case

View attachment 1715095431

Below, the two distributor connections. In the car these are polarity sensitive, but for testing does not matter

View attachment 1715095432

Below, the coil NEG connection

View attachment 1715095433

Below, battery PLUS connection, one wire to this terminal of ECU and jumpered over to + side of coil


View attachment 1715095434

Below, all hooked up and ready to test (except for battery ground). Should produce sparks at least 3/8" and typically 1/2" long

View attachment 1715095435

Below, distributor "one wire" test. I have removed the other distributor wire for simplicity. Take the bare connector end or this clip lead (the yellow) and with everything hooked up, ground it repeatedly. Each grounding should result in a spark (In this photo you need to hook up the ECU ground wire, I left it off for the photo)

View attachment 1715095436

The software on this God Damned site pisses me off so much it is incredible. Can't even post a GOD DAMN old post and get the GOD DAMN photos to show up!!!!!

Had to HAND COPY the entire GOD DAMN thing

Here's a post I made about the simplest way I know to get across testing the ECU/ ignition parts

You need a coil, the ECU and the distributor

Lay it out on the bench. Follow the diagram. Find the two distributor pickup terminals on the ECU. Hook them to the distributor

Hook the ECU case to battery NEG

Coil does NOT need grounded

Distributor does NOT need grounded.

Hook coil + to the power lead terminal on the ECU. Get a clip lead hooked there and let dangle. This is your battery "hot" when you are ready

Hook something from coil "case" to a probe for testing spark.

Hook up your power clip lead. Twist the distributor shaft while holding the test probe near the coil tower. The thing should make sparks

If not, unhook distributor. Take first one, then the other pickup clip leads, and "tap tap" ground them at the battery connection. Coil should make 1 spark each time you do so.

If not, try another coil. If that does not fix it replace the ECU

IF you hook it all up and it WORKS, then there is something AFU in the car harness. SUSPECT a bad ECU connector OR a bad DISTRIBUTOR connector
=============================================
This is all you need to test the basics of the ignition. You can easily test the ballast separate. A battery, the ECU, distributor and a coil, and of course some test leads

(copy image location......................)





Below, the basic diagram for a 4 pin ECU



Below, the wire for testing spark. I use my 12V test light. No, LOL the spark won't blow up the bulb



Below, the ground connection. ALL you need is one wire from batt NEG to the ECU case



Below, the two distributor connections. In the car these are polarity sensitive, but for testing does not matter



Below, the coil NEG connection



Below, battery PLUS connection, one wire to this terminal of ECU and jumpered over to + side of coil




Below, all hooked up and ready to test (except for battery ground). Should produce sparks at least 3/8" and typically 1/2" long



Below, distributor "one wire" test. I have removed the other distributor wire for simplicity. Take the bare connector end or this clip lead (the yellow) and with everything hooked up, ground it repeatedly. Each grounding should result in a spark (In this photo you need to hook up the ECU ground wire, I left it off for the photo)

Happy Joey?? ARE YOU HAPPY??

Bear in mind that the wiring in each photo is only showing that part of the instruction for clarity.............

Some generalities

Suspect the distributor pickup connector. This is prone to bad connections and corrosion.. Remove ALL connectors and inspect them with a light for corrosion, and "work" them in/ out several times to scrub the terminals and to "feel" for tightness

Inspect the distributor for reluctor strike damage, shaft wobble and bushing looseness, and for debri and rust on the pickup or reluctor

Hook you meter, when set to LOW AC volts to the distributor connector and crank the engine. Distributor should generate about 1v AC

With the key in "run" take the disconnected engine harness end of the distributor connector. Tap the exposed end on ground. Should generate a nice hot single "snap" spark from the coil each time

DO NOT check spark with a resistor coil wire. "Rig" a test gap such as a store bought tester, or an over-gapped plug, with a solid core wire. System should generate at least 3/8 nice hot blue spark and typically more like 1/2" long

Measure coil+ voltage when in "run" and when in cranking. Should have AT LEAST 10.5V in crank

MAKE SURE ECU box is grounded. FOR SURE

Don't assume the ECU (or any other connector) is "good." I have found others have found, a poor connection at the ECU. THAT IS ONE REASON WHY in the test suggestions above, I USE CLIP LEADS to test

Big thanks once again, did some testing over the weekend, it only wants to spark when the coil gets a full 12v, or atleast straight from the battery (sparks when wired straight from battery to coil are small and white, only when the coil wire is very close to the tower, plug wire spark is orange). The battery was kinda tired anyways and lately it hasnt wanted to hold charge very well, I let it charge on 10 amp for maybe 15 min yesterday and it started smelling, before that on saturday you could hear a slight boiling noise within the battery on 10 amp. Since the new timing chain was installed it hasn't cranked quite as fast as it used to for whatever reason. Don't know alot about batteries but i'm going to test with a known good one tonight and see where that goes, I tested all components and nothing seems to be an issue.

The only other odd occurrence was with the ballast resistor, I know that on a 4 prong like mine the 2 circuits have different resistance levels, I wasn't sure if I had my 12v switched on the correct circuit, gave the same power to 1 prong on each circuit, the opposite circuit from what I had been using showed more voltage on resistance side, until I plugged the connector for the coil + on the prong, then it barely showed any power on the prong or coil wire. Also don't know what to think of that.