Update: I got an ecm today I took it off a truck identical to mine .. will this one work ?

Gotta replace ecm the first pic is mine out of my truck and the 2nd one is the one i found out of an early model 04 will it work?

 

Short anwer no

 

I don't think so either but further research is required plus what transmission corresponds to each ECM.



Just for reference, here is the original ECM info on my 2004.5 manual trans truck.

 

Ecm that came off my truck reads
C/m-CM848D
P/N-3971104
S/ N 65473
D/C 06/23/2004
ESN 57219358
FIC. S90140.06
It’s a 04 3500 HO automatic
•Today I got a ecm off a 3500 04 Ho automatically identical to mine here’s the tag
C/m Cm848D
P/n 3971104
S/n 1332
D/C 12/19/03
ESN 57133770
Fic s90140.05

• my question is can I just stick this new AC ECM on my truck and it works or do I have to go get it flashed to my VIN number?

 

ECM needs to programmed for VIN and any security , transmission option.

 

Dealer told me they couldn’t do it and I called another they said it’s a 50/50 chance it will work?? They just BS? Or they being fr

 

What is the issue with your original 2004.5 ECM? Will an OBDII scanner even connect to it?


Does your 2004.5 have the optional SKIM/RFID/Chip key security system?
Are the original keys, gray and kinda thick plastic? SKIM keys.
Or are they black and kinda thin plastic? Non-SKIM keys.

If you are not sure, you can get a blank ignition key cut and try it.
If your 2004.5 truck has the SKIM security system, the truck will start and run for about 10 seconds and shut off with a basic metal key.
Lol, if the truck runs that is?!

If your truck has the Skim system, you definitely need to configure the new ECM with your truck's VIN.


If you truck doesn't have the Skim system, that 3rd ECM you posted is worth trying.

If the used replacement ECM has SKIM active, the engine wont stay running.
It will have a mismatched VIN but should work. Not sure how the ABS module and other modules air bag will react.
OBDII scanner to see if the ECM is alive.


Short of that, there is a mostly reputable ECM rebuilder on this forum. You may pursue that option.
Those used ECM's you have are worth money. Hang on to them for now.

@autocomputerspecialist@gm

 

Wire harness 60way , got a short in it and over time it got the ecu hot and melted the inside .. I was getting positive off of a ground wire coming from the 60way plug lol.. I’ll check my keys when I get out there tommorw . The my OG ecu my code reader won’t detect it anymore. But the 3rd one I posted it will crank and try to start but I keep getting codes for circuit #1 injector-#4 .. so I’m trying to track down a used harness today and hopefully it’s a match .. ill Post keys later

 

It was my old
Harness I replaced it today ..

 

Thats not good
Like mentioned can try ACS, some ECMs issues are fixable.


can go to

FCA RAM

fcacommunity.force.com

get info on truck


If you tried to install ECM with wrong VIN, and SKIM usually the truck thinks it is being stolen and will lock out itself out .
if you dont have SKIM and try to install ECM with wrong VIN, or not following the proper procedure, the other modules on the Bus wont be able to communicate and will not work properly .
Gonna need to find and fix any wiring issues , find shop that can write to ECM, most Dealerships wont/cant as they buy preprogramed ECMs

Some owners have been able to contact Smarty and get recovery file to reflash ECM .
can try to contact them discuss
MADS Electronics - Contact us


good info how to install modules and for wiring/code diagnostics can get FSM here

Newbies guide to your new to you truck

First off welcome to CumminsForum! Lots of smart guys here that have seen a lot. VIN Lookup... https://www.cumminsforum.com/threads/newbies-guide-to-your-new-to-you-truck.1909713/page-11#post-29385439 Service Manuals (PM me if the link is not working, use Adobe to open them) Updated Links...

www.cumminsforum.com

 

I

Thats not good
Like mentioned can try ACS, some ECMs issues are fixable.


can go to

FCA RAM

fcacommunity.force.com

get info on truck


If you tried to install ECM with wrong VIN, and SKIM usually the truck thinks it is being stolen and will lock out itself out .
if you dont have SKIM and try to install ECM with wrong VIN, or not following the proper procedure, the other modules on the Bus wont be able to communicate and will not work properly .
Gonna need to find and fix any wiring issues , find shop that can write to ECM, most Dealerships wont/cant as they buy preprogramed ECMs

Some owners have been able to contact Smarty and get recovery file to reflash ECM .
can try to contact them discuss
MADS Electronics - Contact us


good info how to install modules and for wiring/code diagnostics can get FSM here

Newbies guide to your new to you truck

First off welcome to CumminsForum! Lots of smart guys here that have seen a lot. VIN Lookup... https://www.cumminsforum.com/threads/newbies-guide-to-your-new-to-you-truck.1909713/page-11#post-29385439 Service Manuals (PM me if the link is not working, use Adobe to open them) Updated Links...

www.cumminsforum.com

thanks. I got bought another harness and double check the wire and fixed any issues I seen and re loomed them ..

Only thing different from this harness then my Og one is on pin 17 there is a wire coming out .and it’s Been cut . And idk what it goes to cause my harness don’t have that wire ..


and I don’t have a skim key .. I’m actually driving it at the moment .. and I already sent my old ecm to get fixed .. but I had to get something cause it’s my work truck , I’m a diesel mechanic. I used to work for Case HI before I went on my own ..

 

Long story short fca driver burnt up so I sent my OG ecm to SIA Electrionixs to get rebuild
So while I was waiting on them I found another ecm off a truck exactly like mine .stuck it on there and boom it worked … worked for a whole 2 days then burnt yhe fca driver in it too.. so I took off every harness cleaned everything checked every wire .. taped and loomed all back up and stuck back on truck ..
Then notice my fuse box 32-37 have ground coming out of fuses instead of positive . Figured out that had something to do with my trailer connector cause I have no power back there
Currently still working on that
Buy got my old ecm back stuck it on .. hook up my scan tool so I can seem ecm and watch the data .. well can’t detect the ecm .. so I evens tried 3 more different scanners and non of them can detect it .. so I put the 2nd ecm back on and even tho it was messed up it still detected it …. So I put my Og back on and it will start ( got injector sticking bad so it runs like dog crap) but still can’t read anything to do with ecm from tool..
Going to call them Monday and talk to whoever and see what the hell is up

 

IDK, sounds like Bus is down could be wiring could be installing ECM that was not programmed
Post 10 has resources for properly diagnosing