This is interesting... especially since you say it is there long enough for your clamp-on to register current flow and process it into a displayed value long
enough for a human to easily read on the display. Must be at least a couple seconds ...maybe longer?? Sounds more like an intentional pulse rather then
a transient spike due solely to cap charging up to steady state condition. Did it ever drop to a constant nominal lower level? You have my curiosity peaked!
Now I'll have to see what happens on my '05 PS with a improvised 4 screw power converter board.

Looking at my old test data taken on the converter board in a stand alone bench setup which I previously posted many years ago, it appears I did not post what
would be equivalent to key-on engine-off data state for just the converter board (idle no load). I must have dismissed this as minimal and insignificant at the time of
all the failures. Seems my interests were more on normal functioning of just this board at the limits I could control stand alone. That being basic operation where the
converter delivered steady output of minimally 46V and normal operation (statistically limited by my limited samples) at a low battery voltage of 9.7V while drawing
42 amps.Then at a steady state running condition where input Battery voltage was 13.5V and output at about 48V with 8 ohm load drawing about 6 amps.

With the board out of the housing it did not become of concern with over heating during the few minutes of testing, observation and recording the results. Your
suggestion of an 85 amp pulse at key-on engine -off for a measurable period of time may suggest that the PCM was diddling with the converter board in some
way even though it did not have what was eventually finalize as the injector induction preheat function. From my material readings it was my understanding that
Ford (IH) played with this function several times until it was finalized some time after 2007 via service bulletin??? All this time it has become vague for me with
the passing of years.

At the ebay price of $39.88 NEW ... just swap out the board and one can stock up and replace every couple years, after all how long will the 6.0L continue???

My ammeter has a peak function, so it's not readable by the human eye. However, I believe the normal current while the injectors were going through the test phase was ~20a.

The recorded video is old on my old Mac with corrupted video files, so it's not easy to access. I have videos on it I need, and it's been challenging to find someone who can get it sorted out. I'm more of a windows guy than a Mac, and Mac handles images and video files differently.

Even if I fire it up, the photos app where the files are will need to do its thing. A restore from Time Machine takes a few days. It probably would be easier just to do it again tomorrow. That will depend on when I get up as I need to go farming.

I would not really spend time at this point. I'm not sure it would yield any useful information, was the meter in AC/DC mode?
The net peaks would probably be integrated in some form through the function of the meter, a scope would be appropriate
and more relevant.

DC mode. A scope would have been more relevant; I don't have one.

Why would you set it to AC?

I was just going to say a current probe and amp for a good scope would be the only way you are going to get any excellent data.
The sad thing is I have a very nice Tektronix scope sitting on the bench with the ability to record events and export them as a
file. The item I don't have is the current prob and amplifier to get that type of reading.

The scope I am talking about is this one. BTW, that is the output from the fan speed sensor. That scope I believe supports an amp probe and amplifier.
https://cimg8.ibsrv.net/gimg/www.for...b6c4c8fe92.jpg

Things like the spool valve coils tend to get the simple meter treatment. Sorry for cutting off the lower edge of the display line with that horrid angle.
The reading should be 5.13Ω
https://cimg1.ibsrv.net/gimg/www.for...892d93bd9d.jpg

So we'll just ignore it because it's only an ammeter.

Did I say that?
a good scope would be the only way you are going to get any excellent data.
With an ammeter, you are still going to get info.

after over 45yrs in the industry using the top end Tek, and HP/Agilent/Keysight-AKA scopes I have been too cheap to buy one...:-X19 never expecting to need one at home. My small project I could take to work and work on after hours or weekends. The one time I attempted to buy one on ebay it was a fraud deal, ebay would not make good on the sellers fraud but fortunately I paid thru pay pal and they made good with a refund! NEVER AGAIN WITH EBAY !!

That said, Yahiko... what is the lowest volt/div range on your scope and If one is comfortable with experimenting and applying ohms law? Then applying say a 0.126 ohm resistor (50ft of 14ga copper insulated wire=0.12625 ohm) in series in the ground lead for just the FICM as TooManyToys pointed out in previous post of the wiring diagram? One has a current probe for making current measurements (not as good as Hall sensor but will work). Taps could be made every 10ft to have a variable resistor. Ground lead of the scope would connect directly to the chassis bolting point along with one end of the resistor, then the other end of the resistor is connected to the disconnected ground lead of the FICM along with the live lead of scope probe so one is measuring across the coil of wire( large coil say 1 ft dia to min inductance), Viola a current probe!!

You guys are going to make me go out and buy a scope after over 45yrs!! I will probably try a ham fest this time, but next for my area isn't until Oct 22 ? Maybe I'll look into one of those cheap PicoScopes, seems to much marketing hype to be true esp after working with $100K+ high end scopes/analyzers??

I found the video files, and made another today. Amps were higher than I remembered from 5 years ago.

Sorry Jack ... I'm not convinced those numbers are due to the FICM alone??

I may have to try out one of those PicoScopes myself to be convinced. :-X15

Nothing else connects to that 10ga between the grounding point and the FICM.

So I installed a known good FICM and still have the exact same scenario. At this point I’m stumped. I’ve checked all the fuses, I have all the powers and grounds at the FICM. I know the CAN wires are good because if I unplug the FICM I get a lost communication code for it. Any other ideas of things I could try?

What are you using to check for codes?

What is your logic voltage?

Do you get FICM sync when cranking?

TooManyToys, I guess that leaves the PCM doing something complex in the FICM at power up. Maybe the FICM powers up with
some or all of the injector drivers turn on? Would it be only a momentary turn on transient or are they left on until the cycling period
starts or completes or PCM senses engine crank? This is where a scope is better suited for this type of determination rather
then a DC peak current measurement at some random point on the time scale.

The converter board stand alone doesn't exhibit this, main reason I characterize the converter board stand alone to eliminate all the
other possible aberrations outside of the converter board itself. Not sure this peaks my curiosity enough to spent money on a scope
esp after all the past years of personally not owning? I guess the kids could have done without new cloths for a period of time?

But maybe, if I found a good Tek scope calling out to me at a Hamfest. I've been spoiled by my past jobs!! Just maybe???

I’m using a snap on solus and a Autel scanner.

LPWR AND VPWR are both battery voltage, 12.3V. MPWR is a solid 48v

Yes I get FICM SYNC.