LLY Ficm

[kidturbo]

You guys sort that one out. Spent last 2 hours setting up an aws virtual machine just to run SnapOn software, so i can view the scope files captured.. Doesn't like my old win7 64bit... lol

Sent from my SM-S901U using Tapatalk

 

[kidturbo]

Making progress.... Virtual Machines Kick A...

On the LLY, J2-94 on the FICM looks to be reading a raw Crank Signal... While the white wire, is a Tach Signal..
Question 1 solved..

Now who wants to bet an LB7 has 5V Crank Signal on a scope?

 

[kidturbo]

Zoomed that out a bit further just so everyone can verify. I sure know a crank when I see one. But anyone can count those pulses if ya wanna confirm it. That 57x in the schematic, is our reluctor teeth count. Which is same on LB7 and LLY. But we know they have a different Voltage on the pickup. Could it really be that easy?

LLY vs LBZ Reluctor Wheel.

3 holes on LLY, 4 holes on LBZ. 57 teeth LLY, 58 teeth LBZ. Same apparent "timing" based on TDC indicator and timing holes. Both based on a 60 tooth wheel, with 3 or 2 teeth removed.

www.duramaxdiesels.com

 

[kidturbo]

@1FastBrick also so graciously captured us a control line scope. Which is 5v signals, as seen in previous videos. Not best capture resolution to count the us on our pulsewidth, but ya can make out the difference between Pilot and Primary. But the timing and dwell us is tucked in there, which is all we really needed to know anyways.

 

[kidturbo]

Last screen shot of the morning. Our white wire on ECM C3-37.




200mV signal, X pulses per revolution. Could be cleaned up some with filter, but tool has no option on the saved data.

What X is =, to late to do that math. But is where the "Tach Adapter" came in on my stand alone build I recall. Totally irrelevant to this topic, but now we know they added that extra wire for a tach application in something.

Our FICM utilizes a raw crank signal. Likely to identify TDC on #1 as a ref I would guess. Quick check of the J1939 data when I get a minute, and think we can call the LLY research side of this done for the moment.

 

[2004LB7]

Zoomed that out a bit further just so everyone can verify. I sure know a crank when I see one. But anyone can count those pulses if ya wanna confirm it. That 57x in the schematic, is our reluctor teeth count. Which is same on LB7 and LLY. But we know they have a different Voltage on the pickup. Could it really be that easy?

LLY vs LBZ Reluctor Wheel.

3 holes on LLY, 4 holes on LBZ. 57 teeth LLY, 58 teeth LBZ. Same apparent "timing" based on TDC indicator and timing holes. Both based on a 60 tooth wheel, with 3 or 2 teeth removed.

www.duramaxdiesels.com

View attachment 117132

I count 57 pulses on the zero. Or in other words, it looks like the signal is 12 volts that gets pulled to 0 when it senses a reluctor tooth. Looks like it's inverted from what I would have expected. But I do count 57 on the bottom and 56 on the top not including the gap signal. Maybe swap probes?

 

[2004LB7]

Do you have an actual FICM hooked up or is this all just what the ECM is pumping out?

Can you capture the injector command along side the crank to see the relationship between the two? If you have an FICM could you use your crank simulator to vary the signal from the injector command and see what the injector pulse does?

 

[1FastBrick]

Do you have an actual FICM hooked up or is this all just what the ECM is pumping out?

Can you capture the injector command along side the crank to see the relationship between the two? If you have an FICM could you use your crank simulator to vary the signal from the injector command and see what the injector pulse does?

Does this answer your question on how it was captured?

 

[1FastBrick]

It's still set up and I can try and filter or capture what ever you want. This is my personal truck and I would like to not cut or damage anything. The scan tool with scope is also my personal unit. I will need to move the truck before Monday morning so I don't press my luck any further...

Ken has been a huge help to make sure I was able to get the right data this far for this project.

As for that other FICM, the LBZ build has pulled all my financial resources... I can chip in towards it if it helps. I can plug it in and test it too.

 

[2004LB7]

Does this answer your question on how it was captured?

View attachment 117142View attachment 117143

Ok, so he's still working on the data you captured. I was under the impression he set up his bench setup with the ECM and maybe even an FICM but was mistaken

 

[1FastBrick]

Ok, so he's still working on the data you captured. I was under the impression he set up his bench setup with the ECM and maybe even an FICM but was mistaken

Correct! He is trying to secure some of the stuff needed to make a bench set up for this application.

He also has a line on an LB7 truck so he can capture the type of data.

 

[kidturbo]

Yeah unless someone can beat me to it, I'm gonna go run same tests on a lb7 tomorrow.

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[1FastBrick]

If you have an FICM could you use your crank simulator to vary the signal from the injector command and see what the injector pulse does?

So to better answer your question. I sent him captures of all 3 signals at IDLE and at 1500ish RPM.

I am not sure how long it will take him to acquire the stuff to build an LLY bench unit. As we know, good FICM's aren't cheap. An LLY ECU is around the $500 mark give or take right now. Used Wire harness's are almost as bad as good LLY FICkeM's...

 

[2004LB7]

FICkeM's

 

[1FastBrick]

@2004LB7 So did you want me to try and capture something specific? Or try and add a filter to something I tested?

 

[2004LB7]

@2004LB7 So did you want me to try and capture something specific? Or try and add a filter to something I tested?

I think we will need to wait for Ken. I don't think you will be able to test what I am looking for. The timing relationship between the Cam signal and injector trigger signal and how it effects the injector pulse. You would need some way to separate the two so that you can see what happens if the two are not in perfect sync

What I am trying to figure out is why there are individual injector signal wires unless all it does is provide the PW for balancing. If there was no balance then all could be run off a single line. The timing of the pulse would be the difference between the injector signal and the cam signal.

If you wanted you can measure two or more, if you have multiple probes, injector trigger signals and see if there is any timing difference or are they all set the same. If they are all timed the same that would explain why they used the cam signal. If they are all pulling high with respect to when each injector is supposed to fire then the cam signal seems redundant. If it's redundant then we wouldn't even need it for a home brew version. Would simplify things considerably

 

[kidturbo]

FICkeM's

Get this hashed out, say we name this hack the FUCM...

 

[1FastBrick]

I think we will need to wait for Ken. I don't think you will be able to test what I am looking for. The timing relationship between the Cam signal and injector trigger signal and how it effects the injector pulse. You would need some way to separate the two so that you can see what happens if the two are not in perfect sync

What I am trying to figure out is why there are individual injector signal wires unless all it does is provide the PW for balancing. If there was no balance then all could be run off a single line. The timing of the pulse would be the difference between the injector signal and the cam signal.

If you wanted you can measure two or more, if you have multiple probes, injector trigger signals and see if there is any timing difference or are they all set the same. If they are all timed the same that would explain why they used the cam signal. If they are all pulling high with respect to when each injector is supposed to fire then the cam signal seems redundant. If it's redundant then we wouldn't even need it for a home brew version. Would simplify things considerably

I didn't see your edit till now.

Technically, it's a 4 Channel lab scope. Just not sure how convoluted the data would look with out a bigger screen. It can be done though.

 

[kidturbo]

I think we will need to wait for Ken. I don't think you will be able to test what I am looking for. The timing relationship between the Cam signal and injector trigger signal and how it effects the injector pulse. You would need some way to separate the two so that you can see what happens if the two are not in perfect sync

What I am trying to figure out is why there are individual injector signal wires unless all it does is provide the PW for balancing. If there was no balance then all could be run off a single line. The timing of the pulse would be the difference between the injector signal and the cam signal.

If you wanted you can measure two or more, if you have multiple probes, injector trigger signals and see if there is any timing difference or are they all set the same. If they are all timed the same that would explain why they used the cam signal. If they are all pulling high with respect to when each injector is supposed to fire then the cam signal seems redundant. If it's redundant then we wouldn't even need it for a home brew version. Would simplify things considerably

That's not a bad Idea.

If we look at FICM pin 94, and say control lines for Injector #1 and #3 at same capture, should give us a better idea of how they used that crank trigger data. My guess is it's just a reference to determine RPM for voltage and such.

To get the complete picture, will require a bench setup with scope on all 9 lines and EFIlive monitoring the related PIDs. Then we can create a map of full RPM scale and see if anything strange jumps out. GM used 8 control wires from ECM for a reason. If you look at an LB7 ECM, it's exact same hardware used on a 6.0L gasser... I found one in a box here, and thought it was for a gasser, till I ran the OS #.

So my guess is GM cobbled together an OS to run on the existing hardware, then had Bosch build that FICM to be a signal amplifier. I've explored doing the same with some aftermarket ECU manufactures. Easy to fire injectors with correct timing and pulse width using a 5v sig, but then ya gotta amp it up to the injector specs. So the FICM was born...

Stole the whole idea from Ford..

 

[1FastBrick]

That's not a bad Idea.

If we look at FICM pin 94, and say control lines for Injector #1 and #3 at same capture, should give us a better idea of how they used that crank trigger data. My guess is it's just a reference to determine RPM for voltage and such.

To get the complete picture, will require a bench setup with scope on all 9 lines and EFIlive monitoring the related PIDs. Then we can create a map of full RPM scale and see if anything strange jumps out. GM used 8 control wires from ECM for a reason. If you look at an LB7 ECM, it's exact same hardware used on a 6.0L gasser... I found one in a box here, and thought it was for a gasser, till I ran the OS #.

So my guess is GM cobbled together an OS to run on the existing hardware, then had Bosch build that FICM to be a signal amplifier. I've explored doing the same with some aftermarket ECU manufactures. Easy to fire injectors with correct timing and pulse width using a 5v sig, but then ya gotta amp it up to the injector specs. So the FICM was born...

Stole the whole idea from Ford..

If they stole it from FORD... it really is a FUKM...