No crank after 32RH to NV3550 swap on 2002 TJ 4.0

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toohak

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united states
***This is my first time on the forum and I apologize if this is in the wrong section***

So I underwent the easy task(not apparently) of swapping my jeep out from an automatic to a 5 speed manual.

Everything is hooked up and I replaced the PCM with one for the appropriate transmission but I am getting no crank,
So far I have tried:
swapping back the original pcm
replacing the crank position sensor
checking fuses and relays.

Jeep acts like it is just done with life, doesn't crank, no guages work(The radio and odometer do work, as well as exterior and interior lights)
The obd2 port does still work and reports no error codes, the onboard diagnostic doesn't report no pcm eiher.

I am very lost and have quite the headache from this, any help would be greatly appreciated.
 
toohak said:
***This is my first time on the forum and I apologize if this is in the wrong section***

So I underwent the easy task(not apparently) of swapping my jeep out from an automatic to a 5 speed manual.

Everything is hooked up and I replaced the PCM with one for the appropriate transmission but I am getting no crank,
So far I have tried:
swapping back the original pcm
replacing the crank position sensor
checking fuses and relays.

Jeep acts like it is just done with life, doesn't crank, no guages work(The radio and odometer do work, as well as exterior and interior lights)
The obd2 port does still work and reports no error codes, the onboard diagnostic doesn't report no pcm eiher.

I am very lost and have quite the headache from this, any help would be greatly appreciated.
Click to expand...

Do you have a clutch inner lock? Did you replace the wiring for the auto for a manual or how did you do it?

@Eddie Greenlee just swapped a 5 speed to 32RH so he might be able to help.

@mrblaine might be able to help also as he does this a lot more.
 
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Wildman said:
Do you have a clutch inner lock? Did you replace the wiring for the auto for a manual or how did you do it?

@Eddie Greenlee just swapped a 5 speed to 32RH so he might be able to help.

@mrblaine might be able to help also as he does this a lot more.
Click to expand...
I do have one, and probably wrongfully, I re-used the auto wiring harness as everything seemed to plug in correctly.
 
toohak said:
I do have one, and probably wrongfully, I re-used the auto wiring harness as everything seemed to plug in correctly.
Click to expand...

Do you still have the auto trans? Try plugging the Park/Neutral safety switch in and see what happens? That would be my first guess.
But the gauges not working has me stumped.

What year rig?

Edit: Fill out your profile information as it helps others to try and help you with questions.

Do you have a FSM for the year of your rig? Have you looked at the wiring diagrams?
 
Wildman said:
Do you still have the auto trans? Try plugging the Park/Neutral safety switch in and see what happens? That would be my first guess.
But the gauges not working has me stumped.

What year rig?

Edit: Fill out your profile information as it helps others to try and help you with questions.

Do you have a FSM for the year of your rig? Have you looked at the wiring diagrams?
Click to expand...
Sorry I should have included that. It's a 2002.
I do have the original PCM but I don't have the trans anymore. There is very limited info I can find about this swap but I did see something saying to ground some pins for the auto safety switch? The gauges are what I can't figure out either. That part really doesn't make any sense at all to me.
 
toohak said:
Sorry I should have included that. It's a 2002.
I do have the original PCM but I don't have the trans anymore. There is very limited info I can find about this swap but I did see something saying to ground some pins for the auto safety switch? The gauges are what I can't figure out either. That part really doesn't make any sense at all to me.
Click to expand...
I don't know if this helps at all but it if I put the key in none of the gauges do anything for ~10 seconds and then lights such as the gas light come on(full tank of gas). The light for the e-brake is working too
 
toohak said:
Sorry I should have included that. It's a 2002.
I do have the original PCM but I don't have the trans anymore. There is very limited info I can find about this swap but I did see something saying to ground some pins for the auto safety switch? The gauges are what I can't figure out either. That part really doesn't make any sense at all to me.
Click to expand...

These rigs are VERY sensitive to not having things grounded. But I couldn't offer any help in that area since I haven't looked at it.
You need to get a FSM for your year rig and start tracing wires and make sure all your grounds are done.
I just got done blending a Jeep and Dodge Ram wiring harness for a V-8 swap and there are a lot of grounds that have to be done.
 
Wildman said:
These rigs are VERY sensitive to not having things grounded. But I couldn't offer any help in that area since I haven't looked at it.
You need to get a FSM for your year rig and start tracing wires and make sure all your grounds are done.
I just got done blending a Jeep and Dodge Ram wiring harness for a V-8 swap and there are a lot of grounds that have to be done.
Click to expand...
I was afraid of this. I was hoping it'd be something that was common. I appreciate all of your help.
 
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Xposure said:
When you installed the clutch pedal does it have the clutch safety switch plugged in? It wont crank without that working properly.
Click to expand...
It does, I think I narrowed it down to the '00 pcm not working in my 02. I'm supposed to pick an 03 pcm tomorrow I'm hoping that will solve my problem
 
toohak said:
It does, I think I narrowed it down to the '00 pcm not working in my 02. I'm supposed to pick an 03 pcm tomorrow I'm hoping that will solve my problem
Click to expand...

OK that is at least ONE of your problems. 1997 to 2000 used a CCD type process to communicate. 2001-2006 uses a PCI type format to communicate so yes trying to use the older PCM will be a problem. Hopefully this will fix all your issues and you can test out your new transmission tomorrow.

This is one of the reasons when trying to troubleshoot things like this giving a forum ALL the information is very important.
 
Wildman said:
OK that is at least ONE of your problems. 1997 to 2000 used a CCD type process to communicate. 2001-2006 uses a PCI type format to communicate so yes trying to use the older PCM will be a problem. Hopefully this will fix all your issues and you can test out your new transmission tomorrow.

This is one of the reasons when trying to troubleshoot things like this giving a forum ALL the information is very important.
Click to expand...
I appreciate the detailed response. So in theory as long as the 03 matches my engine and trans there shouldn't be an issue?
 
toohak said:
I appreciate the detailed response. So in theory as long as the 03 matches my engine and trans there shouldn't be an issue?
Click to expand...

No it should work fine. I don't know that it will fix all your issues but it solves the no bus problem.
 
toohak said:
This is my first time ever even messing with a transmission, if this takes care of it I'll be very happy. This has been a very helpful forum and I'm glad I found it.
Click to expand...

Well welcome to the forum and hope you stick around. There is a lot of good information here.
 
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