Need some help with 2.5 wiring

[wingnut]

New to the forum. Hello all.

To keep this post reasonable short on September 27 my son totaled his 99 2.5 Wrangler TJ, he got T bone, I told him I would fix it it's his pride and joy. Nine months later here I am. New frame, new tub,paint, POR 15, Raptor Liner I could go on but the list is endless. I rebuilt the used 4.0 that is currently in it.

So here is my problem, wiring I am a Tool Maker wiring is not my thing. I can use a meter but that is the extent of it.
Anyway here is whats happening. No Bus no gas gauge reading fuel pump works. Running lights work, no headlights. No starter engagement when I turn the key. New Computer/ flashed

I have check every ground that I KNOW of, firewall, behind the gauge cluster, right side kick panel, grounds near the front speakers, grounds located on the inside of the grill by the lights. I have checked every fuse and relay, I do have power to both fuse boxes. Crank sensor is plugged in. I have removed the gauge cluster and cleaned the terminals, removed the plugs from the dash and manually plugged them in.

I do have Two 02 sensors that are not plugged in, as of late last night I could not locate the wires. I have a couple of plugs under the dash drivers side right foot location that are not in use, I can't find anything that they plug into. I also have two on the passenger side firewall that are not in use here again I can't find anything for them.

Thanks in advance for your help.

 

[Wildman]

WOW I want that shop......... Nice boat also....


You said it was a 2.5 model Jeep but then say it has a 4.0 in it now? If so did you change the wiring harness when you swapped engines?
A No Bus issue a lot of times is the plug going into the rear of the gauges/instrument cluster. Do you still have the old PCM? If so hook it up and try it to see what happens.

 

[wingnut]

WOW I want that shop......... Nice boat also....


You said it was a 2.5 model Jeep but then say it has a 4.0 in it now? If so did you change the wiring harness when you swapped engines?
A No Bus issue a lot of times is the plug going into the rear of the gauges/instrument cluster. Do you still have the old PCM? If so hook it up and try it to see what happens.

Thanks

Yes I used the harness that came with the motor. It did not come with a PCM thus the reason for the new one. I did use the original 2.5 interior harness, I was told it would work just fine.,

 

[Wildman]

Thanks

Yes I used the harness that came with the motor. It did not come with a PCM thus the reason for the new one. I did use the original 2.5 interior harness, I was told it would work just fine.,

What year is the engine? & harness?

If you still have the old 2.5 PCM install it and see what happens. Just becasue you have a new/rebuilt PCM doesn't make it good. If the engine will start/run with the 2.5 PCM it will just run on 4 cylinders. But it is a good way to test things.
The headlights are another issue. One thing at a time.

 

[wingnut]

What year is the engine? & harness?

If you still have the old 2.5 PCM install it and see what happens. Just becasue you have a new/rebuilt PCM doesn't make it good. If the engine will start/run with the 2.5 PCM it will just run on 4 cylinders. But it is a good way to test things.
The headlights are another issue. One thing at a time.

2000 stamped on the block, the guy sold it to me as a 2001.
I will try the 2.5 PCM. Thanks for the information that helps I didn't think the 2.5 PCM would do anything.

Thanks again

 

[Wildman]

2000 stamped on the block, the guy sold it to me as a 2001.
I will try the 2.5 PCM. Thanks for the information that helps I didn't think the 2.5 PCM would do anything.

Thanks again

Okay that is your issue. If the wiring harness is from a 2001 they had changed to a PCI type communication to the dash. Your sons Jeep is a CCD style. You need to find a 1998-2000 wiring harness.

 

[wingnut]

Okay that is your issue. If the wiring harness is from a 2001 they had changed to a PCI type communication to the dash. Your sons Jeep is a CCD style. You need to find a 1998-2000 wiring harness.

The interior wiring harness? His Jeep was a 1999. Just to clear things up I am using the 1999 interior wiring harness with the 2001 firewall wiring harness.

 

[Wildman]

The interior wiring harness? His Jeep was a 1999. Just to clear things up I am using the 1999 interior wiring harness with the 2001 firewall wiring harness.

Yes the 2001 harness is not compatible with the 1999 harness. At least this is my understanding. Also you need a PCM for a 2000 or older TJ. I might be mistaken but from what I know you need a engine wiring harness that is from 1998-2000. Some 1997 harnesses would also work but there were changes made thru the year so it's just better not to mess with them.

 

[qslim]

I can't speak to the wire harness year combo thing, but for the purpose of getting everything back to the way it was I would head over to the Resources Forum and grab the factory manual. Section 8W is all things wiring, to include pictures of the harness routings, ground locations, individual connector pin-outs, etc. If you're using two different years for the dash harness and engine harness you might need to look at 2 sets of pics, but you might at least find a ground or something that you missed. Or you can look at the pictures of the connectors and see if there's a wire that's missing.

https://wranglertjforum.com/threads...ice-manuals-fsm-technical-documentation.4618/

 

[wingnut]

The interior wiring harness? His Jeep was a 1999. Just to clear things up I am using the 1999 interior wiring harness with the 2001 firewall wiring harness.

I put the old PCM in and I have the same results

 

[Wildman]

I put the old PCM in and I have the same results

Which leads me to believe I might be correct about the wiring harnesses not being compatible. I would ask @RangerRick if he happens to log into the site.

 

[qslim]

Which leads me to believe I might be correct about the wiring harnesses not being compatible. I would ask @RangerRick if he happens to log into the site.

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.

 

[Wildman]

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?

 

[qslim]

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.

Google says that they switched from CCD to PCI in 2000 or 2001 depending on the source. What's interesting is that the wiring diagrams for both 99 & '01 both say "CCD+"/"CCD-" for the databus signals coming out of the PCM. Makes it seem like the tech authors might have kept the CCD nomenclature in the manual despite the change?

 

[Wildman]

Google says that they switched from CCD to PCI in 2000 or 2001 depending on the source. What's interesting is that the wiring diagrams for both 99 & '01 both say "CCD+"/"CCD-" for the databus signals coming out of the PCM. Makes it seem like the tech authors might have kept the CCD nomenclature in the manual despite the change?

Yes this is what us engine swappers have gone thru also. I'm almost certain it was in 2001 but am not 100% sure of this. And who knows it could have been a mid year change?
It's like my early made 1997 that was made in 01/96 has different wiring than a 06/96 and later model.

 

[qslim]

Yes this is what us engine swappers have gone thru also. I'm almost certain it was in 2001 but am not 100% sure of this. And who knows it could have been a mid year change?
It's like my early made 1997 that was made in 01/96 has different wiring than a 06/96 and later model.

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.

 

[reddvltj]

Google says that they switched from CCD to PCI in 2000 or 2001 depending on the source. What's interesting is that the wiring diagrams for both 99 & '01 both say "CCD+"/"CCD-" for the databus signals coming out of the PCM. Makes it seem like the tech authors might have kept the CCD nomenclature in the manual despite the change?

The interior wiring harness? His Jeep was a 1999. Just to clear things up I am using the 1999 interior wiring harness with the 2001 firewall wiring harness.

Yes this is what us engine swappers have gone thru also. I'm almost certain it was in 2001 but am not 100% sure of this. And who knows it could have been a mid year change?
It's like my early made 1997 that was made in 01/96 has different wiring than a 06/96 and later model.

2000 model year is a transition year. There are 2 different configurations, Federal Emissions and CA emissions. The Fed model runs the '99 2 O2 sensor design and the CA model runs with 4 O2 sensors.

 

[Wildman]

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 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.

 

[qslim]

2000 model year is a transition year. There are 2 different configurations, Federal Emissions and CA emissions. The Fed model runs the '99 2 O2 sensor design and the CA model runs with 4 O2 sensors.

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?

 

[Wildman]

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?

I would guess by build sheets and/or part numbers on the wiring harness?