Scrat 2.5 to Scrat Limited 5.9

You are correct. The gauges do not work. I have video but its to large to post.
This gets moving forward finishing up the loose wiring and moving onto drive shafts.
I am going to Clarksville TN this weekend to see my newest grandson. Right across the street from the campground we stay at is a pull a part so I am hoping to find a PCM there

OK good to verify.
I use YouTube for all my videos then I don't have to worry about the size.

Congratulations 🎊 on the grandson.

PM me your address when you are ready for the scanner. You can set your fuel sync with any PCM. Once set it won't change.
 
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No Jeep work although I did get a stock air intake from the junk yard but look at this!

IMG_9063.jpg
 
Well I live 7 miles fro. Florida so stop by if your in the area 😀
You're on. Was hoping to make it this winter but I have ran out of time to get stuff done on the motorhome and the Jeep isn't ready. But I'll be headed that way once everything is done.
 
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Having trouble finding a PCM. I have three now and only one runs the engine but my gauges do not work.

I bought a 98 PCM from a guy online. He sent me pics of the PCM and then did a video of him installing it in his truck and driving it but when I got it and put it in my Jeep, it turns over but does not start up.

is there a place to go where I can research and find a group of part numbers of PCM,s that should work?
Every time I ask wither a junk yard or a person on line about what they are selling they do not have all the information I need. Or they try to tell me what I am doing wont work etc...

any help or ideas would be appreciated.
 
I just dealt with practically the same problem. I believe you have 2 separate and unrelated issues here - the gauges and the PCM. I'm not positive about this so someone feel free to fact check me, but I don't think that a CCD PCM will run a PCI bus (or vise versa) so your PCM shouldn't be related to the gauges not working.

Initially my gauges didn't work either and I'll check my wiring diagrams and notes when I'm not at work. Off memory, check your 5V supplies and your generator field source wiring coming off the alternator. My issue was a simple fix and I'd imagine yours is as well. Have you checked to see if the OBD2 port can read the PCM?
 
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Having trouble finding a PCM. I have three now and only one runs the engine but my gauges do not work.

I bought a 98 PCM from a guy online. He sent me pics of the PCM and then did a video of him installing it in his truck and driving it but when I got it and put it in my Jeep, it turns over but does not start up.

is there a place to go where I can research and find a group of part numbers of PCM,s that should work?
Every time I ask wither a junk yard or a person on line about what they are selling they do not have all the information I need. Or they try to tell me what I am doing wont work etc...

any help or ideas would be appreciated.

If it helps any I went thru 3 bad PCM's when I first did my swap and it wasn't until the 4th that I found a good one.

https://www.ebay.com/itm/2340356712...d=link&campid=5337789113&toolid=20001&mkevt=1

https://www.ebay.com/p/1123647384

https://www.ebay.com/itm/1856629752...d=link&campid=5337789113&toolid=20001&mkevt=1

https://www.ebay.com/b/ECUs-Compute....9L+360Cu.+In.+V8+GAS+OHV+Naturally+Aspirated


I bought my last PCM off Ebay and had my vin programed into it also. Unless you live in a state that has emissions testing and requires the vin in the PCM to match the vehicle this isn't a issue.
I honestly do not know why you have two that won't run the Jeep. Do they start and then die within 3-5 seconds? If yes then that is the SKIM or alarm system. It's why Durango or Dakota or Grand Cherokee PCM's don't normally work. Those vehicles came with skim or a alarm system and unless you have the BCM the PCM won't work. And we don't have a BCM on our Jeeps.

Since the one PCM allows it to run you at least know your wiring is good. Now it's finding a PCM that will work your gauges. Or use the one that allows the engine to run and run aftermarket gauges.


I just dealt with practically the same problem. I believe you have 2 separate and unrelated issues here - the gauges and the PCM. I'm not positive about this so someone feel free to fact check me, but I don't think that a CCD PCM will run a PCI bus (or vise versa) so your PCM shouldn't be related to the gauges not working.

Initially my gauges didn't work either and I'll check my wiring diagrams and notes when I'm not at work. Off memory, check your 5V supplies and your generator field source wiring coming off the alternator. My issue was a simple fix and I'd imagine yours is as well. Have you checked to see if the OBD2 port can read the PCM?

They could be related or they could be separate. A CCD PCM will not make the gauges work if it's a PCI vehicle. But he's looking at the correct years of PCM's. You need a 1998-2000 if it's a 97-2000 TJ and then a 2001-2006 TJ is PCI.
The one PCM that is allowing his engine to run but the gauges not to work COULD be a 1996 0r 1997. These years will allow the engine to run but because Dodge didn't go to the CCD bus in the trucks until 1998 they won't make the gauges work.
 
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I just dealt with practically the same problem. I believe you have 2 separate and unrelated issues here - the gauges and the PCM. I'm not positive about this so someone feel free to fact check me, but I don't think that a CCD PCM will run a PCI bus (or vise versa) so your PCM shouldn't be related to the gauges not working.

Initially my gauges didn't work either and I'll check my wiring diagrams and notes when I'm not at work. Off memory, check your 5V supplies and your generator field source wiring coming off the alternator. My issue was a simple fix and I'd imagine yours is as well. Have you checked to see if the OBD2 port can read the PCM?

Thank you. I did plug into the obd2 port and it reads the pcm. I will check the wiring of alt tomorrow
 
Hope you can get it figured out.

The 1998 one you said will crank but no start? Did you check for spark & fuel? Because you said you have one that makes it run I would guess it's not grounds or ASD. Does it try to start?
 
Hope you can get it figured out.

The 1998 one you said will crank but no start? Did you check for spark & fuel? Because you said you have one that makes it run I would guess it's not grounds or ASD. Does it try to start?

yes it turns over and will until I let off the key. but no start, I plug the other one that runs the motor back in and it fires right up. strange to me just not sure where to go from here.
 
So have had more time to look into this issue.... I check codes and got 1388 which lead to ASD relay. Found a short there!!! reset codes and got the engine running and gauges working now!!! Such a great feeling! Thank you all for the suggestions and help!

That is awesome NEWS.... Sometimes all it takes is stepping away and talking to others. I've done that on more than one occasion during my whole build.
So what is next? What do you have left to do to it at this point? Will you be driving it to work soon?
 
So have had more time to look into this issue.... I check codes and got 1388 which lead to ASD relay. Found a short there!!! reset codes and got the engine running and gauges working now!!! Such a great feeling! Thank you all for the suggestions and help!

Great work. Electrical gremlins can be a pain.
 
Cool swap! Is that the gc front dress,fan and shroud? Also i missed what year tj you have?

On the axle swap issue consider a super 35 kit over the 44hd. Probably a better choice.

On the transfercase side an sye is cheaper for the 231 and it is an inch or so shorter.wider chain and 6 pinion planetary is a simple junkyard swap.but a 242 would be cool for launching that tj.awd and a 5.9 will throw you back hard compared to a 2.5
 
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