Ok, electrical geniuses got a puzzle for you

2006_LJ

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Long Island, NY
As I've posted on here before, I'm down a rabbit hole searching for a high charging alternator. Changed, PCM, Big 7 cable upgrade and a reman alternator — voltage still reads 14.8. But wait theres more!!!!!!!!! When doing the big 7 upgrade, I decided to look under my PCD and it looks like the PO did some funny wiring, which I undid while I was there to turn it back to stock. Not an electrical genius but I do know how to solder.

I wonder if undoing what the PO did is why, I am now having a crank but no start issue, intermittently — like I can crank it forever without turning over. Key word "intermittently"

Any ideas as to what he was trying to do? and if it relates to my problem? . — Red X is where the wire is cut, green line is where new wire is tapped/added

Also attached as PDF if its easier to read than the image

Untitled presentation.png
 

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That looks just a whole lot like the TSB 25-001-07 mod, an official Jeep mod for dealers (or owners) to perform to fix an emission monitor problem in the OBDII system. But your schematics look somewhat different from the 2005 FSM I used for mine. I think the 2005 and 2006 FSM are pretty identical on those schematics, so what schematic are you using? If the PO (or his dealer) did it right, and you undid it, you didn't do yourself any favors.
 
If your OBDII system will never report that all emission "Monitors" are complete, you do that mod, and then it works right. Gets you to pass emissions inspection in those nasty states which use the full CA emissions standards, like CO (and a few others, I suspect).
 
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I wonder if undoing what the PO did is why, I am now having a crank but no start issue, intermittently — like I can crank it forever without turning over. Key word "intermittently"
Agreed, it looks like it had the TSB done.
Cranking without starting is also what you'll get when you wire a kill switch to the ASD relay.
 
As I've posted on here before, I'm down a rabbit hole searching for a high charging alternator. Changed, PCM, Big 7 cable upgrade and a reman alternator — voltage still reads 14.8. But wait theres more!!!!!!!!! When doing the big 7 upgrade, I decided to look under my PCD and it looks like the PO did some funny wiring, which I undid while I was there to turn it back to stock. Not an electrical genius but I do know how to solder.

I wonder if undoing what the PO did is why, I am now having a crank but no start issue, intermittently — like I can crank it forever without turning over. Key word "intermittently"

Any ideas as to what he was trying to do? and if it relates to my problem? . — Red X is where the wire is cut, green line is where new wire is tapped/added

Also attached as PDF if its easier to read than the image

View attachment 374919

That looks like the TSB was done to your Jeep. Check the voltage with a scan tool and see what it reads.
 
I'm not familiar with the TSM mod, so I can't comment on that, but I just wanted to mention 14.8V is not overcharging, or I'm misunderstanding something.
 
1. Thank you to everyone for responding, sorry I didin't get to this earlier, currently travelling for work. — I will check into that TSB and it looks very familiar to what my wiring was like — and Yes I am in NY so we have strict emission laws.

2. I was using this thing that kept saying my alternator is over charging — then using a multimeter I keep getting readings of 14.7-14.9 — also glad to hear this is OK!


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Agreed, 14.4 is textbook I think, but in my opinion under 15 is still fine.

Boiled my battery coming back from Colorado in August. I have the same issue. Weather the battery failed and shorted internally and the new battery will survive I don’t know. I have installed a external regulator for now until I can dig back into it.
 
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1. Thank you to everyone for responding, sorry I didin't get to this earlier, currently travelling for work. — I will check into that TSB and it looks very familiar to what my wiring was like — and Yes I am in NY so we have strict emission laws.

2. I was using this thing that kept saying my alternator is over charging — then using a multimeter I keep getting readings of 14.7-14.9 — also glad to hear this is OK!


View attachment 375271
Do you have a scan tool? I am interested in the voltage reading you are getting from the pcm through the scan tool.
 
Do you have a scan tool? I am interested in the voltage reading you are getting from the pcm through the scan tool.

Do not have a scan tool, unless you mean the obd scanner ? Would really like to get to the bottom of this after all the work I put into it :(
 
Boiled my battery coming back from Colorado in August. I have the same issue. Weather the battery failed and shorted internally and the new battery will survive I don’t know. I have installed a external regulator for now until I can dig back into it.

Do you have a dual battery set up?
 
14.8 volts shouldn't hurt anything. Most modern vehicle electronics use components that can handle much higher voltage. I wouldn't recommend it, but I've seen vehicle charging systems upgraded with dual 8 volts batteries for 16 volt base, charging at 18.5 volts using externally regulated Leese Nevil alternators, where they would boost the voltage up to 21 durring peak load useage, and the only issues experienced were some of the light bulbs / headlights didn't last as long as normal. The computerized parts are the ones most likely to have issues, but they should be fine to at least 16 volts. But like I said, I would never recommend doing any of this to anyone, but 14.8 volts is nothing to worry about.
 
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nasty states which use the full CA emissions standards, like CO (and a few others, I suspect).

It's actually only about 6, maybe 7 counties in Colorado that do that. I get the feeling most of the people in those counties aren't even aware that their southern neighbors in Colorado Springs don't have to deal with that nonsense.
 
It's actually only about 6, maybe 7 counties in Colorado that do that. I get the feeling most of the people in those counties aren't even aware that their southern neighbors in Colorado Springs don't have to deal with that nonsense.

Just like folks don't know that we have counties here in CA where you don't have to get stuff smogged, at all.
 
It's actually only about 6, maybe 7 counties in Colorado that do that. I get the feeling most of the people in those counties aren't even aware that their southern neighbors in Colorado Springs don't have to deal with that nonsense.

Yes, I always have to consider where a vehicle comes from in CO before buying. I would love to move somewhere farther from Denver.

Just like folks don't know that we have counties here in CA where you don't have to get stuff smogged, at all.

True, I didn't know that.