LLY Ficm

2004LB7

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I think you are right about it being used on other engines before the Duramax. I too googled the EDC15C7 and they look identical. I wonder if the internal programming is the same or different. If it's the same then you may have just opened up a whole new source of FICMs for likely a lot lower cost.
 
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2004LB7

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Little more googling. That EDC15C7 isn't a match. Close but seems to only have the ability to drive maybe 4 injectors. The internals are different. Looks like for some engines it is the ECM and runs everything. Would make sense why there is so many "unused" pins in these FICM's.

So either Bosch redesigned the EDC15C7 or another one that looks identical or more then likely it's a a different one we haven't found yet

As you can see in this picture. There is only drivers on one side

ECU_1.JPG_ZXnQcDh.resize.jpeg
 
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1FastBrick

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@kidturbo I know someone that should be able to write code for the andrino. Let me know what you need so I can discuss with him.

Do you need the pedal and harness from that LB7??? I can go see if it still there.

Been working on LS stuff for a buddy who's truck has been down. I will be finish the motor and getting it droped in today.
 

kidturbo

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Little more googling. That EDC15C7 isn't a match. Close but seems to only have the ability to drive maybe 4 injectors. The internals are different. Looks like for some engines it is the ECM and runs everything. Would make sense why there is so many "unused" pins in these FICM's.

So either Bosch redesigned the EDC15C7 or another one that looks identical or more then likely it's a a different one we haven't found yet

As you can see in this picture. There is only drivers on one side
Nice work. Glad to see I'm not only one feels this was a full fledged ECU once upon a time. That FB guy across the pond might actually be helpful to identify this Isuzu board version. Seems to know his way around all the Bosch code too.

From my experience owning and hacking around on the MB 3.2L CDI [now considered one of the best diesels ever built] I noticed how close it's ECU was in design to the E35A/B of same period. Similar units also found in the WV/Audi V10. However if ya do your reading, VW actually used 2 ECMs on that V10 because nothing was out there to fire "10" Bosch Injectors... One unit was main brain, while other was basically in standby used as a FCIM, and to control the second VGT if I recall. Been a decade since I last read about that layout.

I have noticed over the years that EU gurus are pretty knowledgeable on the internals, have all the bin files, and like hacking around known issue of these Bosch units. I also agree this GM FICM has way to many extra pins and processors to have been designed to do this single job. I'll happily hit a few FB forums for any other clues to where or what this board might fit. Post up some good LLY board pics, and I'll crack open this DOA LB7 box today.

Also when ya get a minute, trace out those spliced together small pins they used to drive injectors 7 and 8, and maybe we can figure out how that works. What is difference between 1-6 and 7-8 circuitry. Because while I would love believe this is a Dumb Driver box, the more I see, I believe it's fully CPU controlled, and someone dumbed down the code..
 
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kidturbo

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@kidturbo I know someone that should be able to write code for the andrino. Let me know what you need so I can discuss with him.

Do you need the pedal and harness from that LB7??? I can go see if it still there.

Been working on LS stuff for a buddy who's truck has been down. I will be finish the motor and getting it droped in today.
That would be great if could find someone to write us a sketch to run those 8 control wires.

Link to the Ardu-Stim project files; https://github.com/speeduino/Ardu-Stim

I believe the Arduino Uno has enough digital IO ports to replicate a 60-3 crank signal, along with the 8 control lines for the injectors. What we need is to replace the CAM wheel sections of that code with an update to power ON/OFF 8 control pins in a "firing order" to signal injectors. Something fairly simple, 1 injector fires every 90deg of crank wheel, or 45 of CAM wheel. Equals about every 15th tooth on the crank wheel that we need to add a pulse for an injector. 1+45deg, then 2,3,4,5,6,7,8 then start over.

I can assign the wires to FICM to match GM firing order. Would be nice to have an adjustable "dwell" time for each pulse. Along with easy way to Reverse ON & OFF for all 8 pins, since seems LB7 and LLY are backwards in the control voltage.

Easy enough right? Probably require a conference call or chat to sort the details.. But yes, any help with coding be handy to make a simple desk top test rig anyone involved could use to test these design changes off-truck.

And yes could use a pedal and pigtail if ya see one rusting away...

Pic of the std board used for Ardu-Stim builds. $20 on Amazon if anyone wants to play along.

37ea344d95f1867493cbd38befe0b9b5.jpg
 
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PureHybrid

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So what's the end goal here? A whole drop in unit that'll switch from LB7 to LLY, or a board that will replace existing piece inside the oem housing?
 

kidturbo

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But first, gonna need to understand how much data the ECM and FICM are exchanging, and if a truck will run without that J1939 connection. At first I would have said no problem, but now kinda leaning to the FUCM"e",, this is a more complicated design....

Sent from my SM-S901U using Tapatalk
 
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kidturbo

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I did a quick search of that Infineon 859398 processor on that EDC15C7 board posted above, and came up with this ECU Bin File site.

Where when you type in EDC15, it brings up a whole bunch of new options to review.

2685 Products found​


Lots of Chrysler products listed as running that same ECU. That short lived deal with Daimler, sure brought the Bosch side some major sales. Oh how the web deepens...
 

2004LB7

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Ken, from the sound of it. You are almost making an ECM with that Arduino. If you had the code to look at the crank signal to time the injector control and something to control the fuel regulator valve. That's everything needed to fire up an engine. Even if it's just to idle it.

Also, are you telling me I didn't need to buy a truck to test these FICM's on? I could have just bought a $20 little board that would be shipped to my home 🤣
 
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1FastBrick

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Ken, I went and got you an LB7 pedal and the pigtail. Let me know where to send it...

FICM, ECU, and TCU were gone.

20230904_151617.jpg
 

1FastBrick

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That will work perfect. I can't bring myself to hack the ECM plug off that LB7 Kodiak chassis harness. Now I can just wire up the lugs to a battery, figure out an ignition switch, and save a good harness for someones future stand alone build.
No need now and it was cheaper at the Bone Jard than just a pedal on FleaBay. I will send it out tomorrow, you should have it by friday. I marked the switch in the position as I removed it. Then you can use a flat blade screwdriver to increase the throttle position on your bench set up.
 
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kidturbo

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Received a little LLY bin data from a buddy tonight relating to CANbus. Good and bad news IMO.

Bad news first. ECM build lists under [Parse], the two "Proprietary" PGN files being sent by the FICM, along with normal J1939 transmission data. Meaning this is data it's listening for to use in who knows what. Defuel, ect.
  • 59904 - Standard PGN Requests
  • 61442 - ETC1 - Transmission
  • 61445 - ETC2 - Transmission
  • 65280 - PropB_00 - FICM
  • 65281 - PropB_01 - FICM

It also lists under [Build] these two NEW Proprietary PGN's. Which means it's sending these to something on the bus. I see it also sends some Environmental PGN data out, so maybe these 2 are GPCM related. We can only hope.. But certainly requires more research to define how important, and if FICM is listening to anything to make decisions.
  • 65300 - PropB_14
  • 65301 - PropB_15 TX & RX
  • 65269 - AMB - AAT, CAT, IAT data

Good New: Looks like both the LB7 and LLY receive those same 2 Proprietary PGN's from the FICM. So with a little bin file hacking, if we could figure out how to reverse the injector signal ON/OFF voltages, then a LB7 FICM should run no problems on a LLY...