Of course you could test the coil, ballast resister, ignition switch and all the wiring in between, by simply, MOMENTARILY, grounding the negative side of the coil (ignition switch in "run" position) to a know good ground, while holding the high tension lead (coil output) near the block (grounded), you should get a spark when you remove the temporary ground lead on the negative side of the coil. The spark should repeat each time you ground the coil.
The odds of seeing that split second where the switch is on are much more in your favor if you have an oscilloscope. Since a multimeter is much more commonly used, you are very unlikely to see the voltage at anything less than 12v nominal on either side when testing it. This is particularly true with a digital meter.
Because I understand how it works, thats how I know.
The presence of 12v on the negative side (measured at the connector to the ECU) means the circuit is working fine. Funny how those factory test procedures actually test what they are designed to test.
Crack open the FSM and get back to me on this.
Ok, do I need to review with you that the circuit is NEVER grounded until the engine is turning? And that the circuit is only grounded for a split second? This since a build up and collapse of the coil field is designed to happen as quickly as possible. Therefore, if you want to see the circuit in a grounded condition, you need an oscilloscope. At all other times, the coil will show 12v nominal on both sides. Thats twice that I've explained this to you. One more time, and we're done here and you fail.
Yeah, because you are never wrong.
Except if you had read his test results, you would know that the pickup coil had the required resistance.
WRONG. So wrong, its hard to believe you actually posted that. The bolt is not permanently affixed to the ECU or the car body. Thus, rust can form betwen the bolt and the ECU OR between the bolt and the car body. Your test only shows how well the bolt is grounded. Thus, the proper test (which I posted from the FSM) is to go from pin five to the battery negative and look for continuity.
Ok, let me rephrase for you textbook types that have never troubleshot this system in reality. What I suggested was a test to see if the ignition switch was cutting power to the coil (as in, NO power) when in the "start" position. What I suggested is not a test for the coil circuit. The test for the coil circuit was to look for battery voltage at the 1,2 and 3 cavities in the connector to the ECU. If you dispute this last sentence, please take it up with the factory engineers.
6.5v is too low. Look for a problem between the battery and the ignition switch, and then to the ballast resister, and then to the coil positive. This voltage would indicate that cavity two isn't getting battery voltage like it should to pass the test procedure.
If all those fail to show 12v or the required voltage by your FSM (mine calls for 12v) suspect the ignition switch as the cause. Also, its possible the ammeter is doing weird things, as its in the circuit.
That voltage seems a bit on the low side. Unplug the ballast resistor and try measuring voltage again while cranking. If you have no voltage then you have a problem with the ignition switch and if it is still at around 6 volts, I would reconnect the ballast resistor and attempt a jump start (even if it seems to be cranking ok). This could be nothing more than a bad battery.
They are NOT "after the primary circuit, in fact, they control it. They take the place of the points in a standard ignition system as far as triggering the spark. The difference is that they don't deal with the voltage and current from the coil that points do, that is handled by the ECU. Did you check the air gap between the reluctor and the pickup coil with a non-magnetic feeler gauge? You are not getting spark because either nothing is triggering the coil or the coil is bad. To test the coil, connect your jumper wire to the negative side of the coil and with the ignition on and holding the coil wire near ground, connect you jumper to ground and then remove it again. You should get a spark every time you remove it from ground.
I am very familiar with this ignition system after dealing with it for many years.
That just simplifies the system and removes more possible points of failure.
Here is something else to look at. Does the distributor rotate when you are cranking the engine? I would check this first if you have not already done so.
It is not as split second as you might think and a dwell meter will see it just fine. It will also show up on a multi-meter (especially a digital one) if you set it to AC.
By what you are saying, it really doesn't sound like you understand it all that well.
LOL, all that shows is that the harness is intact, not that the control circuitry or even the ECU is functional.
I don't need the FSM for this, it is far to simple and I have installed these on many mopars, both replacing point ignitions and the troublesome lean-burns.
I think that you need to take a lesson in coil operations. Did you forget what dwell angle means? You do know that magnetic fields take time to build, right?
Sure I am, just not this time. Must you always jump back into your childish mode when someone says something different from your idea? BTW, when have you ever admitted to being wrong about anything?
So what? That doesn't mean that it's position didn't change or that there isn't damage to the reluctor itself. There could also be a short in the pickup to ground but I see that you didn't bother to tell him to check for that. He also needs to unplug the pickup coil from the harness and check for continuity between either lead and a good ground and if any exists, the pickup coil is bad, IOW, it had better be an infinite resistance.
LOL, complete BS. The ECU gets its ground from those bolts and if they are tight and getting a good ground, then the ECU should also be properly grounded. Even you FSM says that if the pin 5 ground test fails, to TIGHTEN THE BOLTS.
It is funny thaty you would call me a textbook type when you are the one reading from the damn book and not really understanding what you are reading.
I thought that we were done? Back to your childish reactions again I see but we all know that is your way to admit to being wrong or not knowing everything that you claim to. Now go study up in that FSM again, maybe you might actually learn how the system works.
That is simply not true. His ECU does NOT get its voltage from the ballast resistor as he has a single resistor and no pin 3 on his unit. Pin 1 gets voltage DIRECTLY from the ignition switch as does the ballast resistor. The coil does get its voltage from the ballast resistor EXCEPT WHEN CRANKING where its voltage also comes directly from the ignition switch! The purpose of this test is to make sure that the ballast resistor bypass during cranking is working. Next time, understand what you are talking about before jumping in to defend your friend and wind up just making an ass out of yourself.
That still doesn't guarantee that the coil is good as there could be a short to ground in the windings that will not be seen measuring terminal to terminal.
That would once again be you Budd. Perhaps you should review the operation before you just jump in and look stupid.
As a matter of fact, I don't know that he did and neither do you.
You know what they say about ASSumptions, right??? In many cases it is the obvious that gets overlooked because everyone ASSumes that it was done when it in fact was not.
If you are trying to ground the ECU, as he is in this case (yeah, a wire from the ECU body to negative on the battery grounds the ECU) connecting the ECU body to the negitive side of the coil would probably really screw up the ECU if it wasn't grounded.
If he were trying to ground the coil with this method, it would be obvious why the truck never started, and might kill the coil.
What you suggest is a bad idea.
But, you know these systems so well, I'll just sit back and watch you post bullshit some more.
No, Tom, the mistake was made by you as you did not mention a single thing about needing to hold the key in the START position to supply voltage to the coil to be measured.
Thank you for screwing up and beginning the name calling as usual.
Btw, the ass is a excellent domesticated beast of burden that is known for loyalty, determination and surprising intelligence.
And I would rather be compared to an ass than to be compared to you.
Since he didn't include the text he was referring to, I took it as he was going to test the coil itself and if so, connecting the temp wire to the coil is easier. If he is attempting to run a wire from the case of the ECU to ground, then he is just wasting his time on your bogus advice.
If he was referring to my previous post, it will cause no harm to the coil and if he simply grounded it that way, then as you said, it would not start.
Once again, you speak without actually knowing what it was about.
It is still in the text below without the caps. Now perhaps you could explain to the rest of us how to crank the engine without turning the key to the start position, unless of course you ASSumed that he would hotwire the starter. You just keep digging deeper.
Once again you are wrong as I didn't call you names, I simply suggested what you were doing to yourself. And speaking of screwing up, what about your BS that the ECU gets its power from the ballast resistor and before you say it, he already said that he had the 4 pin version of the ECU in the post that you replied to.
IOW, the polar opposit of the way you are acting again. Grow up Budd.
I guess that you would rather be compared to an ass rather than a man because you are still not man enough to admit to being wrong or jhaving enough class to just shut up.
If you read the thread, you would have had context on what he was saying, AND my answer to him.
Well, since I didn't advise him to use any sort of jumper wire, this would be more ASSuption on your part.
Says the one who is about a day behind the rest of us and hasn't been reading everything he wants to reply to.
YOU claimed that the coil negative would not have 12v unless grounded. But the FSM clearly states that cavity 2 on the ECU connector will have 12v, and the connector IS the ground for the coil. As such, if its disconnected for the test, and you find 12v as specified, YOUR claim that the coil negative would only have 12v when grounded is BULLSHIT.
Ok, I missed it, so shoot me. But you'll NEVER remember me admitting to this or anyother mistake, will you?
My, my, it was Max you accused of that mistake, not me. You hate me so much you have to yell at me for things I never did.
And you insinuated I was an ass, the same as calling me one.
No, you grow up and practice the tolerance you liberals accuse everyone else of needing to have.
Did someone lie to you about you being a man again? No, Tom, I consider you to be the rectum of the group. Unwiped, hemorrhoidal, full of excrement and happiest when you're in the toilet even when in your usual condition of diarrhea of the brain.
You brag about being receptive of criticism, but you never, NEVER are. If anyone was to dare tell you where you screwed up, it opens them up for one of your vulagar tirades. Max and I seem to be the only ones with the constitution to tolerate your sheer idiocy.
Well, I've wasted my time on you again. I guess I keep hoping for a miracle to take place in you. Ah, well . . . .
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