03 to 05 PCM swap

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chrisp2493

chrisp2493

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Got it all off ebay. Shipped to hotwireauto and they did the conversion. Thats why I tried diablo bc of the comp 260. Had someone send me custom tune. Still stalled. I will have to get it started up to see what codes its throwing

Yeah it’s hard figuring out what’s wrong, I don’t know what hot wires does exactly, you could have a bad tune, you could have a pre-existing problem. How did you hook up the oxygen sensors? Did you at least hook up the new upstream sensor? You’ll need both upstream sensors hooked up, and have the back ones turned off in the custom tune or hooked up correctly.


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Austin Andersen

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Ok guys going to try charging battery tomorrow andstarting her up. What are obvious things I should look for? Im sure its tune and pcm related but just want to do simple quick check to see where I should start. Will take videos tomorrow. Im almost positive pcm is locked up again from diablo tune per previous mechanic.
 

Austin Andersen

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Yeah it’s hard figuring out what’s wrong, I don’t know what hot wires does exactly, you could have a bad tune, you could have a pre-existing problem. How did you hook up the oxygen sensors? Did you at least hook up the new upstream sensor? You’ll need both upstream sensors hooked up, and have the back ones turned off in the custom tune or hooked up correctly.


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Can you give me a call tomorrow if you have time. Want to run my setup by you to see if you have any thoughts on where to start troubleshooting.
4025400017
 
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chrisp2493

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Can you give me a call tomorrow if you have time. Want to run my setup by you to see if you have any thoughts on where to start troubleshooting.
4025400017

I can try to help you out later this evening, I’ll be at work all day and can’t take a call there


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Evilsizer

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would it be better to use a 2005 harness instead or would it work out to be the same using my 03 harness for the swap?

maybe im miss reading something but what about these other sensors the 1500 has in the 05 vs the 03. would it not be better to run a 2500 ecu vs the 1500 because of the sensors? i also ask cause i have found a 2500 5.7 harness for half price of getting a 1500 harness to use. been looking on ebay.
 

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Starts and dies... sounds like SKIM issue..
Need to keep to the basics and get it started and running. Hotwire should of flashed the (03) vin and possibly provided a wiring harness for the needed o2s's. The only added sensor in 05 would be the EGR which is turned off by Hotwire or in a custom tune. It won't keep you from running just throw a code. IMO, it is easier just to add the o2s wiring than installing a complete harness.
 
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mairj40

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Well I'm gonna start this swap. After a few weeks of searching I ordered (what I sure hope lol) is the right pcm from a junkyard in Texas. Found some extra plugs at a local scrapyard. Definitely nervous about doing this, hope everything goes smoothly 37fa9894aad75d2ef4248a4b2d4f184d.jpg

Not to revive an old thread, but are those the only 2 connectors you needed from the 05? I have a PCM and complete engine harness from a 2005 Durango. I know the PCM won't work, but it came with an engine I bought. The only thing that's missing is the blue plug on the PCM. I'm not sure what it is for, but I have the two plugs you show in your picture.
 

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Durango isn't a Ram. There will be differences. Only way to verify for sure is to get both wiring diagrams and compare.
 

mairj40

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Durango isn't a Ram. There will be differences. Only way to verify for sure is to get both wiring diagrams and compare.

Yeah, I've already figured that I won't use the PCM. I'm mainly looking to use the wiring harness. I can get a RAM PCM from the junkyard.
 

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Since you have the entire harness you might try to breakout C4 plug from the harness and see if it takes the place of the tcm splicing needed to populate C4. I would list the tcm wires in a notebook and compare them to C4 wires in the harness. I have a little booklet of numbers and label each wire so I can easily identify and compare in my notebook. This will help you decide whether to splice or use the C4 harness.
 

Hawkfoot03

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Currently putting a high lifter cam in my 03 and am needing to do this swap. Im planning on repinning the new 05 pcm. How do i know which one to order though? Any help would greatly be appreciated.
 
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You need to find one out of a similarly equipped 05 ram, match up the bed length, gas tank size, and transmission.
 

Redtruck-VA

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Currently putting a high lifter cam in my 03 and am needing to do this swap. Im planning on repinning the new 05 pcm. How do i know which one to order though? Any help would greatly be appreciated.

I would recommend swaping the pcm before the cam swap. Then you will be ready for whatever tuning you choose.
The common pcm number I have found is 56028930AB. I used B&G to flash my VIN. They are experienced in swaps. Hotwire also can install vin's #..
The common sellers seen on ebay often screw up by installing the software along with the vin. Good luck..
 

Hawkfoot03

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Thank yall a lot. Its already torn down and in the process of getting the cam put in already. So fingers crossed it all comes together in perfect roaring harmony. Im gonna order the pcm you mentioned, i found a website that has them in stock and the skm system is reset along with my vin and mileage added.
 

Fast69Mopar

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Thank yall a lot. Its already torn down and in the process of getting the cam put in already. So fingers crossed it all comes together in perfect roaring harmony. Im gonna order the pcm you mentioned, i found a website that has them in stock and the skm system is reset along with my vin and mileage added.

Does your truck have SKIM, or a Sentry Key Immobilizer? Do you have a grey key or a black key?

If you have a black key then you want to find a PCM from a truck without SKIM. If the new PCM came from a truck with SKIM you will have a truck that starts and dies because you won't have a key to program to a SKIM Module.

What does the company mean that SKIM has been reset? Are you getting a PCM without SKIM? I'd make sure .
 

Soup1213

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Can anyone help with the rpm signal i seen it on the 03 wiring pin out but not for the 05.

I have a pcm from a 05 and 04 ram 1500 they run the truck fine but trans doesnt function i have manually shift it not worried about this at the moment.
I tried to take it to smog with the 05 pcm and all monitors were set but it couldn't pass due to the smog computer not being able to read the rpms.
Can you get the gauges from the 03 to function normally?
My pcm that originally came with engine is bad and throws a p0443 code soon as you start it
 

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You are asking several questions. C4-11 is the rpm signal. 04 and 05 pcm are interchangeable but not the same. Have you converted the wiring from the 03 TCM to C4 plug?
 

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You are asking several questions. C4-11 is the rpm signal. 04 and 05 pcm are interchangeable but not the same. Have you converted the wiring from the 03 TCM to C4 plug?
No not yet i want to get the 05 pcm working on my 03 hemi engine. Do i take the rpm signal from the tcm?
 

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I'm going to say no. I would wire it up oem first to get it running and operating correctly. I'm using a 05 manual pcm and C4 is blank. Everything works on mine except cruise control. Your dash should be working. Hopefully Chris will drop by to help. He knows this better than I do.
 
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