Inside the CM849B ECM

Printable View

September 6th, 2011
GMPX

Inside the CM849B ECM

Ever wondered what the inside of the 2006-2007 Cummins CM849B ECM looks like?
To get the ECM opened up like the picture below pretty much renders the ECM useless because of the way the case is wrapped around a frame (not shown), the case ends up looks like it's been run over by a bus (so don't try this on your own ECM).

The main sections of the ECM are shown in the picture below.
1 - This is the Injector drive circuit with the big green charge capacitors clearly visible.
2 - The C1 & C2 connectors underside.
3 - The 'brain' section of the ECM with the CPU, Flash memory and RAM.

The CPU is from the popular Freescale PowerPC range, this CPU is used in many ECM's from GM, FORD and Chrysler, to many European cars. The PowerPC CPU core was also once used in Mac's and numerous gaming consoles (Xbox360, PS3, Wii).
Cummins first started using the PowerPC processor as far back as the 2003 model ECM's (CM846), which was years ahead of most other manufacturers (Delphi, Visteon, Bosch) switching to these CPU's for their controllers.
Notice there is no solid PCB as such, everything is mounted on a flexible type PCB, making component level repairs almost impossible.

http://download.efilive.com/Software..._Internal2.jpg
September 6th, 2011
Dmaxink

That's super cool! Glad you posted this
September 6th, 2011
GMPX

No problem, a number of people had asked for something like it.
September 6th, 2011
joecar

Very interesting, flex film PCB.
October 3rd, 2011
dsltnr

Is this a Motorola MPC555 processor
October 3rd, 2011
chance cobb

cool
October 3rd, 2011
GMPX

I can't remember if it was a MPC555 or 563, one of them anyway.
August 10th, 2015
SASDakota

Any chance of doing this for the newer CM2200 and CM2350?
August 10th, 2015
GMPX

Sure, might not be as detailed but I have a few bricked ones that I can pull apart.
August 10th, 2015
GMC-2002-Dmax

Is there a reason to pull it apart Ross, or was it making you mad and you decided that you will gut it just because, LOL

Interesting to see that all that makes a vehicle run
August 10th, 2015
SASDakota

Quote:

Originally Posted by GMC-2002-Dmax

Is there a reason to pull it apart Ross, or was it making you mad and you decided that you will gut it just because, LOL

Interesting to see that all that makes a vehicle run

Maybe he tried to flash this one and it said "PC load letter" so he went office space on it! :Eyecrazy::throw:
August 11th, 2015
WyoFreeride

That would be cool. The engineer in me wants to take everything apart and see whats inside...
August 11th, 2015
GMPX

I think it was a bricked one, because once you prise them open I doubt it could ever be sealed back up again, there is a lot of force and bending involved.