Need some help with 2.5 wiring

I was a generator mechanic in the Army so I played at schematics BUT I have lost a lot of that knowledge due to my injuries so I am struggling right now working on my harness for my swap. Some is coming back and the rest I am figuring out.
You ever need a hand hit me up. I'm pretty good at it because I do it every day for a living. Other stuff not so much..
 
Yeah, I noticed that on the WDs. Certain wires are populated in connectors depending on Fed/CA builds. How does one figure that out, their build sheet?
For the 2000 Model year it's pretty easy to differentiate CA and Fed. models. The Fed model does not have "Pre-Cats" and only has one up stream and one down stream O2 sensor, The CA does have the "Pre-Cats" and 2 of each up and down stream O2s
 
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I took a look at the wiring diagrams (for the instrument cluster at least) & compared 1999 to 2001 - I didn't see any difference. Every plug & pin is identical which makes me think they should be compatible at least for the IC circuitry according to the WDs. But, I haven't ever been involved directly in something like this so I could be missing something.

@wingnut I'd recommend taking a look at your '99 manual and starting on page 8W-90-7. There are drawings of all the connector locations, harness routings, & ground locations. I'd go through the pictures & make sure everything is accounted for. I've done projects like this more than a few times (just not on a TJ) and I forgot to either hook something up or missed a ground lug every time. Hopefully some folks with first-hand experience will chime in soon.

If you want to post up some pics of the mystery connectors that can't find a home post up a pic of them, we'll help you find them. When you put everything back together their pigtail probably ended up pointing the wrong direction or something.
Thanks for your efforts. I will do that this evening. I have a couple more transmission side that I will take pics of tonight and under the dash down I would say shin height right side.

The one on the transmission I have not put much effort into finding I am not to concerned about that one at this point.

plug 1.webp


plug 2.webp


trans.webp
 
Yeah, I'm a wiring schematic nerd. I do it for a living on aircraft so that's what I try to help people out with the most with on this forum. I've noticed that the '97 schematics don't always jive with what people actually have based on their build date.
I can't read a schematic to save my life lol
 
The issue may be the switch from the CCD bus to PCI bus. How this can or could affect things I don't know but I know when doing the engine swaps this creates issues.

What year is the PCM you bought? Is it the engine year or the tub year? Also what year did they change from distributor to the coil pack on the engines?

I would assume 2001 on the PCM, I specified that we I ordered it which is the year of the engine.
A friend on mine brought up two good points last night. Does the PCM have a SIM? I don't know, my key doesn't have a chip.I have a call into Nationwide Parts Wholesalers to see.
One thing he suggested that I do is run a set of jumper cables.. neg side of bat to the dash frame for an additional ground. That didn't change anything. I don't know what year they made that change, yes it does have coil packs.

Thanks
 
For the 2000 Model year it's pretty easy to differentiate CA and Fed. models. The Fed model does not have "Pre-Cats" and only has one up stream and one down stream O2 sensor, The CA does have the "Pre-Cats" and 2 of each up and down stream O2s
This is the configuration that I have. Two up and one down.
 
This is the configuration that I have. Two up and one down.
Something's not right then. I'm not sure what the entire engine harness look like. So I couldn't tell you where to look for the 2nd down stream O2 sensor plug, but if you have an 01 PCM it would be looking for 4 O2 sensors, but that wouldn't cause your issue.
 
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Well I am a little embarrassed. Gent keep in mind I am a tool maker and shade tree mechanic, not a very good one.

So I have been calling all four of these 02's up stream.

And the cat pic down stream. My bad.....

So the question now is the I have the cat in the second pic it has a threaded plug in it, I assumed this one requires another 02 sensor as well ? This is the one that I was referring to when I said that I could not find the plug for.
It's typical of me to just try and figure something out rather than refer to the book.

40L O2 Sensor Locations.webp


cat.webp
 
Get the pictures of the plugs you can't figure out under the dash and that might help with other issues.

Even if you had SKIM it would start and run for approx 3 seconds and then die. I'm still thinking it going to a PCI bus from a CCD bus is the problem but I have been mistaken before.
 
Okay something else I was thinking about.
Do you have any type of code reader that you can hook to the OBD-II port?

https://www.harborfreight.com/zr8-obd2-code-reader-with-live-data-63809.html
Something like this that can also read Live Data? If you do this could help to diagnose your issues. If not see if you can rent one from a parts store? This would help to tell us where you are or aren't getting voltage at.
 
Okay something else I was thinking about.
Do you have any type of code reader that you can hook to the OBD-II port?

https://www.harborfreight.com/zr8-obd2-code-reader-with-live-data-63809.html
Something like this that can also read Live Data? If you do this could help to diagnose your issues. If not see if you can rent one from a parts store? This would help to tell us where you are or aren't getting voltage at.
I think if the problem is with the bus then the code reader isn't going to connect. The OBD port stubs off from the CCD+- wires between the ECU & the cluster. Would be a good way to see if that's the problem though.

Edit: actually I guess that depends on where the CCD/PCI incompatibility is, which I'm not real clear on. Is it supposedly a problem with the early cluster or the harness? If the incompatibility is only with the cluster than I guess you'd still be able to connect...
 
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I think if the problem is with the bus then the code reader isn't going to connect. The OBD port stubs off from the CCD+- wires between the ECU & the cluster. Would be a good way to see if that's the problem though.

This was my idea to know if it is a wiring issue or what?
 
Thanks for your efforts. I will do that this evening. I have a couple more transmission side that I will take pics of tonight and under the dash down I would say shin height right side.

The one on the transmission I have not put much effort into finding I am not to concerned about that one at this point.

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View attachment 172240

Pic #1: AC low pressure switch?

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Pic #2: Hard to tell, how many wires are going to that; 2 or 3?

Pic # 3: Tough to say, one of the ones on this pic maybe?
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1593212724308.webp
 
Get the pictures of the plugs you can't figure out under the dash and that might help with other issues.

Even if you had SKIM it would start and run for approx 3 seconds and then die. I'm still thinking it going to a PCI bus from a CCD bus is the problem but I have been mistaken before.
Will do. Ill post them around 3:00
Thanks
Get the pictures of the plugs you can't figure out under the dash and that might help with other issues.

Even if you had SKIM it would start and run for approx 3 seconds and then die. I'm still thinking it going to a PCI bus from a CCD bus is the problem but I have been mistaken before.
Pic #1: AC low pressure switch?

View attachment 172382View attachment 172383

Pic #2: Hard to tell, how many wires are going to that; 2 or 3?

Pic # 3: Tough to say, one of the ones on this pic maybe?
View attachment 172389

View attachment 172381

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Pic 1. That plug is in the cluster of wires coming off of the plug on the top.
Pic 2. Is behind the dash cover, in the cluster going to the key switch.
Pic 3. Is coming out of top harness running along the firewall.
Pic 4. Is a small two pin in the same cluster going to the key switch.
Pic 5. Is a single pin close to the firewall just above the transmission jump.
Pic 6. (A) A round two pin. (B) 3 wires without a plug. (C) The black plug in the transmission, 2 wires.