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Instructions for 03 to 05 PCM Swap

26648 Views 92 Replies 23 Participants Last post by  Dan22644
Ok here is a rough draft of the PCM swap. I’ll post this for any suggestions, corrections, or added info, then edit and repost. Please feel free to give me any suggestions, I'm no pro at this, just figured I had some time to write this up, and I'm just trying to help out anyone interested in this swap. I know first hand how difficult it is trying to read through 70 pages of info trying to pick up everything you need to know.

I have scans of all the pinouts and diagrams on my computer. I will upload them to this post, but I've noticed the pictures on here don't always show up the greatest. I found all of them in the 03 and 05 service manuals. Here is a website to download the 05 Service Manual. I Found the 03 stickied somewhere else. If you can't find them anywhere else, PM me and I will email you all my scans. These are available free, I had one guy on a facebook truck page offer to email them to me for $50, what a douche :confused:

OEM SERVICE MANUALS

General overview
You will need to add in a new bank of oxygen sensors, Upstream and Downstream. Add wiring from the new sensors all the way to the computer location and pin it to the connectors. You will add 6 new pins, and two wires will splice onto existing wires for a return signal.
Remove the old TCM computer from the truck. Most of these wires will be pinned onto connector C4 on the 05 PCM.
You will need to purchase a NGC connector (C4 Green) with pins. I believe you can order these online, or just go to a salvage yard and cut off a connector or two to use. The pins will come out fairly easily. Pry open the 4 tabs on the connector to remove the back, then use a flat screwdriver to unlock a red holding tab on the side of the connector. Then the pins should pull out with a good tug. The pins can be reinserted, then the red tab closed to lock the pins in solid. It may be beneficial to purchase a few extra connectors, the cover on the back of the plug has a tendency to break very easily.

Downstream sensors can be tuned out with a custom tune to remove any codes if you are not installing catalytic converters. It's recommended to add the wiring and sensors, but is not absolutely necessary in order to work.

O2 sensors-
05 sensor designatons
Sensor 1/1 Driver side upstream
Senor 1/2 Driver side downstream
Sensor 2/1 Passenger side upstream
Senor 2/2 Passenger side downstream

For adding in the new O2 sensors, the 03 truck should have the 1/1 and 1/2 sensors located on the passenger side. On the new 05 setup, Bank 1 will be the driver side; Bank 2 will be the passenger side. On my personal truck, having these reversed caused major issues with the truck running right. I had to switch pins, so my new sensors went to Bank 1 pins, and I had to relocate the existing sensors to the open spots for Bank 2.


Word of caution, it is not recommended to cut the harness off of the new sensor. The sensor wires are typically silver or aluminum, and shouldn’t be soldered to copper. I used Casper Electronics O2 sensor extenders for the connectors; I cut them off and soldered them to the new wire going to the computer.

Connector C1
Switch Pin 31 to 33
Add new Downstream o2 signal wire to pin 31
Splice on new Upstream o2 Return to Pin 32
Add TCM Pin 46 to Pin 26 SCI Receive (TCM)
Add TCM Pin 7 to C1 37 SCI Transmit (TCM)
Add TCM Pin 38 to C1 27 5 Volt Supply

Connector C2
Switch Pin 18 to 17
Add new upstream o2 Heater Control to Pin 18
Switch Pin 31 to 33
Add new upstream o2 Signal
Splice on new Downstream o2 Return to Pin 32

Connector C3
Switch Pin 9 to 10
Add new o2 downstream heater control to Pin 9

Connector C4
TCM Pin 60 (OD solenoid Control) to Pin 1
TCM Pin 59 (4C Solenoid Control) to Pin 2
TCM Pin 40 (MS Solenoid Control) to Pin 4
TCM Pin 19 (2C Solenoid Control) to pin 6
TCM Pin 55 (UD Solenoid Control) to pin 8
TCM Pin 20 (L/R Solenoid Control) to pin 10
TCM Pin 18 (Pressure Control Solenoid Control) to Pin 11
TCM Pin 37 (Ground) to Pin 12
TCM Pin 53 (Ground) to Pin 13
TCM Pin 57 (Ground) to Pin 14
TCM Pin 1 (TRS T1 Sense) to Pin 15
TCM Pin 3 (TRS T3 Sense) to Pin 16
TCM Pin 49 (Tow/Haul Overdrive Off Switch Sense) to Pin 17
TCM Pin 15 (Transmission Control Relay Control) to Pin 18
TCM Pin 16 (Transmission Control Relay Output) to Pin 19
TCM Pin 48 (4C Pressure Switch Sense) to Pin 20
TCM Pin 29 (UD Pressure Switch Sense) to Pin 21
TCM Pin 9 (OD Pressure Switch Sense) to Pin 22
TCM Pin 2 (TRS T2 Sense) to Pin 26
TCM Pin 17 (Transmission Control Relay Output) to Pin 28
TCM Pin 50 (L/R Pressure Switch Sense to Pin 29
TCM Pin 47 (2C Pressure Switch Sense) to Pin 30
TCM Pin 30 (Line Pressure Sensor Signal) to Pin 31
TCM Pin 14 (Output Speed Sensor Signal) to Pin 32
TCM Pin 52 (Input Speed Sensor Signal) to Pin 33
TCM Pin 13 (Speed Sensor Ground) to Pin 34
TCM Pin 54 (Transmission Temperature Sensor Signal) to Pin 35
TCM Pin 42 (TRS T42 Sensor) to Pin 37
TCM Pin 36 (Transmission Control Relay Output) to Pin 38
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Worse case is go to stearlership and get them. I agree though. Plenty of stuff in yards. Dont be set just on truck harness. I got my stuff from a Durango.
Thank you for the info, great write up and very helpful. I have a 03 ram with bad 4.7 that iv decided on swapping in a 5.7 hemi & upgrading to the 05 pcm.
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Thank you for the info, great write up and very helpful. I have a 03 ram with bad 4.7 that iv decided on swapping in a 5.7 hemi & upgrading to the 05 pcm.
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Recently Did this swap myself, had jtotin build my harness. Only issue I seem to be having is I'm getting a P0152 code, Jerry moved the rear O2 wiring to be the B2S1 wiring and I tuned out the rest since it's not required.

Is it possible the code is being set because I left the B1S1 O2 in the OEM placement and didn't move it up the downpipe causing a funky reading?
Recently Did this swap myself, had jtotin build my harness. Only issue I seem to be having is I'm getting a P0152 code, Jerry moved the rear O2 wiring to be the B2S1 wiring and I tuned out the rest since it's not required.

Is it possible the code is being set because I left the B1S1 O2 in the OEM placement and didn't move it up the downpipe causing a funky reading?
Note: P0152 is the OBD-II generic code indicating that the O2 sensor for bank 2 sensor 1 fails to have a lower voltage output below 1.2 volts for more than 10 seconds indicating a lack of oxygen in the exhaust stream or a short to power in the sensor circuit.
There needs to be a cat separating the sensors. Each voltage change is counted as a flip. The forward O2s should have a higher flip count (voltage) than the down stream O2s. If both O2s read the same it throws an code. My rear sensors are still installed and wired, but tuned out. In the early days of these swaps it was thought the sensors needed to be installed and tuned out to not have a code. Mine has sort of evolved to what it is now with a B&G modified pcm and HP Tuning. No codes.. never have been able to get cruise to work..
Note: P0152 is the OBD-II generic code indicating that the O2 sensor for bank 2 sensor 1 fails to have a lower voltage output below 1.2 volts for more than 10 seconds indicating a lack of oxygen in the exhaust stream or a short to power in the sensor circuit.
There needs to be a cat separating the sensors. Each voltage change is counted as a flip. The forward O2s should have a higher flip count (voltage) than the down stream O2s. If both O2s read the same it throws an code. My rear sensors are still installed and wired, but tuned out. In the early days of these swaps it was thought the sensors needed to be installed and tuned out to not have a code. Mine has sort of evolved to what it is now with a B&G modified pcm and HP Tuning. No codes.. never have been able to get cruise to work..
The rear sensors are tuned out along with the EGR. THey aren't required where I am. and have no codes for them.

I am thinking I either need to swap the wiring side to side (since right now bank 2 is driver side and bank 1 is passenger) or I need to move the sensor up into the downpipe and not in the OEM location in the Y where the 03's are. Something to do tomorrow lol
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Skim was removed before computer install

Confirmed Working!! 05 ECM !!!!! will post vids and pics of it running later
Hey bud I did the pcm swap myself but it won't crank it started up the first 3 trys it would turn on then turn off then after that it wouldn't crank any more I tool it to get the skim removed but still nothing would you know what it could be
PCM is locked. First question: did you use an un-SKIM'd 2005 PCM? Second question: did you remove the SKIM from the column prior to plugging in the PCM?
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OK I did even think of the skim when I bought the pcm and I didn't remove the skim but I didn't even know about the skim at the time so took it to a shop and they removed the skim from the coloum and the skim from 05 pcm and still didn't work
If it's locked will I be able to get it unlocked or am I screwed and have to get a new one
OK I did even think of the skim when I bought the pcm and I didn't remove the skim but I didn't even know about the skim at the time so took it to a shop and they removed the skim from the coloum and the skim from 05 pcm and still didn't work
Can you rephrase this so it makes sense? I'm not following.

If it's locked will I be able to get it unlocked or am I screwed and have to get a new one
Yes, it's a simple procedure to unlock a SKIM locked PCM, problem is it's gonna happen again unless you fix what caused it to begin with.
But I took it to unlock the skim but still didn't start and there is no crank I can't figure it out went thru the whole p/n in and outs but they look good but I don't know what it could be so ima look for a 05 pcm with black key
So I have a 03 Laramie. With skim. I cannot get the truck to run. Can't get anyone to build me a pcm with my vin and 05 software. No one will unlock the skim locked pcm.

So looks like I get to undo everything I just did last night and go back to my 03 stuff. Really wish that info would have been out there before I started hacking my harness.

Flagship. Sat on hold for 45 mins. Got hung up on before I could say hello. Then sat on hold again to be told to go fly a kite.

Found some other number on these forums they laughed when they heard Skim.

Dodge told me to fly a kite. And every tuner in the state wants the whole truck to do anything. What a colossal waste of time.
This has been all posted in the past.. all pcm's if plugged into a truck with a skim module will become a skim active. Depending on your emission requirements you may be able to use a mismatch vin ie 05 non-skim junkyard pcm. I have used junkyard pcm with no re-programming and it worked fine. However my final solution was buying a NIB 05 manual pcm and having B&G program only my vin into it. Then tuned it using Diablo CMR tuning. When HP Tuning became available I switched to that.. Whoever you use to tune /write to your pcm, be explicit that the pcm needs to remain unlocked for future tuning. With this all said if the engine doesn't crank, the you have another issue beside skim protection.
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What are the differences between the 05 ram and the 05 durango pcm pin outs? I can't find info anywhere.

So here's the story.
I did the wiring. Plugged in the 05 ram pcm. Hooked up and batteries. Turned the key on, fuel pump cycled and it cranked and wouldn't start. It did this 3 or 4 times. Then it started and died. Started and died.
I then disconnected the batteries and unhooked my skim and tried again, as I forgot I had one. Tried it and same thing.
I stopped did some research and couldn't find any information that would help. So I plugged my solus legend in and had tons of codes. So I deleted the codes and tired again. Start and die. I then went to get into the skim side using the solus legend. It said it wouldn't communicate. So I plugged the skim back in. I deleted skim codes and used the "reset ecu" option under: Skim- functions-reset ecu.

Once this happened now it won't crank. Gauges work. Solus will talk to it. No crank.

So I have three pcms as I was junk yard diving.
The other two are from durangos. One according to the pcms vin is a 04. This one just cranks and won't start. Won't communicate with solus.

The other says 05 in the vin. This one is will start and engine will run. No gauges work. Won't communicate with pcm.

Yes wiring is all correct and O2s added. Plus if you look at what you're splicing it's all relative to the TCM. So I don't see anything you could mess up anyway. Beside a ground. As far as starting, running, and communicating.

I am very frustrated. Feel like I should have just dealt with the 03 issues instead. This truck is a nightmare. Was built and born in Canada and sold in the US.

2003 2500 qcsb 4x4 Laramie auto.
Comp cam, cool valvetrain everything, msd, headers, s&B, full x pipe exhaust. Diablo trinity t1000 with hemi fever.
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Sounds like you are close to solving this. I don't know anything about a solus legend, but sounfs like it is a powerful tool. Once the skim module was plugged in the pcm became skim active and will need reprogramming to remove the skim activation.
03 sucks, Welcome to our Hemi Family!! (y)
2
What are the differences between the 05 ram and the 05 durango pcm pin outs? I can't find info anywhere.

So here's the story.
I did the wiring. Plugged in the 05 ram pcm. Hooked up and batteries. Turned the key on, fuel pump cycled and it cranked and wouldn't start. It did this 3 or 4 times. Then it started and died. Started and died.
I then disconnected the batteries and unhooked my skim and tried again, as I forgot I had one. Tried it and same thing.
I stopped did some research and couldn't find any information that would help. So I plugged my solus legend in and had tons of codes. So I deleted the codes and tired again. Start and die. I then went to get into the skim side using the solus legend. It said it wouldn't communicate. So I plugged the skim back in. I deleted skim codes and used the "reset ecu" option under: Skim- functions-reset ecu.

Once this happened now it won't crank. Gauges work. Solus will talk to it. No crank.

So I have three pcms as I was junk yard diving.
The other two are from durangos. One according to the pcms vin is a 04. This one just cranks and won't start. Won't communicate with solus.

The other says 05 in the vin. This one is will start and engine will run. No gauges work. Won't communicate with pcm.

Yes wiring is all correct and O2s added. Plus if you look at what you're splicing it's all relative to the TCM. So I don't see anything you could mess up anyway. Beside a ground. As far as starting, running, and communicating.

I am very frustrated. Feel like I should have just dealt with the 03 issues instead. This truck is a nightmare. Was built and born in Canada and sold in the US.

2003 2500 qcsb 4x4 Laramie auto.
Comp cam, cool valvetrain everything, msd, headers, s&B, full x pipe exhaust. Diablo trinity t1000 with hemi fever.
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I found this person when looking into LS swap computer info. He also works on Dodge Ecu's. I haven't used him, but he does seem like he knows what he is doing. He doesn't have much on his webpage about other makes, but his facebook page does talk and show him working on others.
Home (customecm.com)
Whatever you do before you try another computer unplug the skim module so it doesn’t security lock you again.
I have run my 2005 truck on 2003,2004,2005 and a 2006 pcm( only to move it) but they all worked non skim pcm and truck
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