bypass ignition module?

bypass ignition module?
Just prior to this starting issue that you are having, did you have the two wires on top of the starter relay disconnected? If those two get crossed, the results are like you describe. Also, you problem does not sound like a faulty icm. The best and most expensive icm is made by NAPAs "Echlin" brand, the ultimite ignition system is an MSD.
 
I didn't mess with anything other then to take out and replace the tach and take out and replace the headlight switch. Again, the headlight switch was in the on position when I put it into the receptacle which accounts for the little spark and the lights coming on upon install. I also heard a CLICK somewhere but had no idea where.
I don't think I'm savvy enough to do anything but replace the original ignition AS as it's a true plug-and-play application. I don't think it's going to be that THAT is the solution but this truck is 201,000 miles old and has seen better days (which is to say anytime I can replace anything "as long as I'm in there" that's what I like to do).
When I was 16 I had my dad's car (Dodge Omni… embarrassing) and I had the same thing happen. Luckily I was at a full-service gas station and the mechanic came out and told me what it was and made a bypass. The next morning I snuck out to the auto parts store and picked up a ballast and replaced it and everything was good as new. (and my dad never knew... ha!). I was really hopeful that that's what it was in this truck, 'twas disappointing to discover that there is no ballast here.
So I'm at a complete loss. I'm still fiddlin'/searchin' and I do appreciate the input. I hope that talking to another mechanic buddy of mine that a solution shows up soon… The weather sure is nice out here in AZ!
 
Tryin' to post pictures but it will only let me post wanted to time.
 
Starter Relay Terminal with the "Redwire" mentioned above repaired and still no start.
 
Ignition coil, I didn't change anything here!
 
Could this relay have gone bad? There is to Evelyn they are located in the wire loom right against the firewall just behind the engine…
 
And what is this thing pray tell? I open the flap on the black plastic sleeve and was able to slide out a card with some resistors on it…
 
Actually, now that I think of it, what replaced the ballast on the older ignitions was the installation of a resistance wire. It is a dark brown wire from the alternator and goes to a junction of the red wire from the ignition module and the red wire coming out of the coil. This is not a wear item like the ballast, but there might be a break in the connection where it goes into the alternator or on the other end where it runs into the red wire at the icm/coil junction. Another check would be to turn ignition key to the on position and you shouls be getting 6 volts at the red wire on the coil.
 
Torxhead said:
resistance wire (dark brown wire from the alternator and goes to a junction of the red wire from the ignition module and the red wire coming out of the coil).
Another check: turn ignition key to "ON", 6 volts at red wire coil.
Click to expand...

Nope & Nope! I sure do appreciate the help Torx. The info on the ballast v resistor wire was familiar, but I'm not sure which it'd be coming from the Alt (pic below)...
View attachment 17559

So that red wire that had the connector was the one I re-soldered just to ensure what you said... that it was a good connection. There is no brown wire from the Alt, but there is one 'floating' around in the engine compartment from the wire loom where other ignition wires go and it is right next to the Alt, with a female connector end... no clue!

Tested the Coil (I think) and get the following reading when connecting the positive lead to the Coil + and the negative lead to the engine block (pic below)...
View attachment 17560
well below 6 volts I should say (that is, if I'm doing it right).

For kicks, and 'cause it was cheap, I replaced the ICM with another Stock Motorcraft (Ford) one, and I replaced the Starter Terminal Relay with a stock one. The headlight switch that 'sparked' when I inserted the switch I disconnected to ensure it was nothin' in there messin' with things, 'twasn't! I also 'multi-tested' the coil and decided not to replace it since the 2 terminal test and the ignition wire & 1 terminal test gave the numbers that it shoulda given. When I took off the ignition wire, started the Jeep an watched the schpark jump, it was a bright orange with a bitta blue in it. Shouldn't thatta been all blue?

Anyway, I'm interested in this Resistor wire as this issue was fixed whilst driving my dad's car with the same symptoms (replaced the ballast, which makes me suspect this 'Resistor' wire). Possibly related, one-a the pics above shows about a credit card size box that had about a credit card sized card on it to which were attached about 10 integrated circuits... don't suppose that's any relation.

Torx, really appreciate your response... makes me think you are the only member and this site just LOOKS BIG! :O)
 
Photo #1 I posed above (dunno how to insert photos into my posts I guess)...
 
... aaaand photo #2
 
LoveMyCj instead of highjacking someone elses thread why don't you start your own with your problem?
 
Looking at your pics, I see what appears to be the original coil, coil connector, and capacitor. That coil, if original should be tested for around 1.35 ohms across the positive and negative terminals. That coil connector has a history of making a poor connection, so keep an eye on that. The capacitor if original, is supposed to mellow out electrical spikes in the system and should be checked for resistance also. That credit card sized box you are referring to looks like the harness plug for the rear.
 
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Coil tested almost exactly like the new OEM one I bought to install (so obviously I won't install it) and as per specs.
Resistor wire is which one? I figure that green wire coming off the coil with the black connector between it and the rest of the wire loom was the noise supressor??? Which is the Resistor wire?
And based on the comment from the guy before you Torx, should I start a new thread? I was just trying to play off the "start/vroom" issue but apparently I've violated a major rule… or something!
 
The resistor is the thin brown wire coming out of the alternator and goes into the icm/coil jonction. There are three wires coming out of the alternator-red, orange, and brown. NAPA does sell them. Three volts is pretty weak to be coming out of the coil positive.
 
Doing some research, it seems that the oem tachometer is wired in series with the ignition, or this is what I have read. You did say that you replaced the tach with a Crown brand. Did it rewire the same way? What colors are the wires going to the oem tach?
 
I'm not sure what "wired in series with the ignition" means but the tach wiring diagram from Painless Performance (Ford, Delco and MOPAR) shows tach source like this:

View attachment 17570

Ignition Coil NEGATIVE (-) terminal to tachometer source.

-Jon
 
From what I have seen in a few diagrams JD, there are different ways to hook up an oem tach. There seeems to be one type of circut where if the tach is disconnected the "run" circut will not operate and a little wiring rework has to be done.
 
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