Your EEC-IV has some specific information on it:
EEC-IV: Electronic Engine Control version 4
EFI-SD48E: Electronic Fuel Injection - Speed Density E4OD ( SD48E: 7.5l, SD48B: 5.8l, SD47A: 6cyl) *note* this is my interpretation
F6TF-12A650-AJA: Engineering number(F: decade, 6: year, T:model, F:department, 12A650: base part number, AJA: revision
BOX0: calibration/strategy/software code running on the hardware(EFI-SD48E).

Basically all SD48x hardware are the same, the software is different.

 

Mine has EFI-SD48E7C18 on it. Does that make a difference?

 

Everything makes a difference.
You really want BOX0 if your looking for a replacement.

Other SD48E will work, if they are in good working condition, but the fuel maps, emissions, and shift points may or may not be different.

I put an EEC-IV SD48B from a F250 in my F150, and it shifted horribly.
Probably due to the software/calibration/strategy differences (fuel map, shift points, etc) of having a heavier truck EEC in a lighter truck.

 

If I order one from some online company how does the BOX0 come into play? I've called several companies and they only asked for the F6TF number. Even when I called the Ford dealerships they didn't ask about the BOX0 number.

 

It's this number F6TF-12A650-AJA, specifcally the -AJA part, is the revision, emissions, etc.
They have parts books that reference the engineering numbers and emission calibration numbers, not the strategy numbers like BOX0, BCC0, etc.

 

Ok. It makes sense now. Last time I dealt with an ECU problem like this I went to the salvage yard and pulled one with the right color grommet and all was good. Thanks for the help and education. I may be able to get this anemic road slug moving again.

 

Hello, looks like some people in this thread of some experience with this already so maybe I can post my question here instead of wasting thread title space on a new post.
I have a 1994 F700 (medium duty according to Ford) service truck with a 7.0L (429ci) gasoline, auto transmission, single speed rear differential that has burned a hole in its ECM board. The ECM has the following info on it:


Apparently this is a unicorn, because locating the "F1TF" ECM to replace it yield little to no results. What are the thoughts on getting a F2TF-12A650-HA and slapping it in there? or F3TF or F4TF if available? Looks like the engine went to a 7.5L in the later dated models, which may just mean the computer will be trying to figure out where all the intake air is at? fuel compensation? but not fail catastrophically (as long as firing order is the same, or wire my spark plugs how the ECM wants them to be).
I have a request for the exact part with ModuleExperts, so they're on the lookout for me as well. Hometown dealer couldn't help and recommended a few truck places around which so far have all told me the same story of "F1TF is available right now." I had tried sending the unit for a rebuild, but CarComputerExchange deemed it "non-repairable, unit has major damage to board from blown caps, cannot repair" (any other recommendations, but I dont think anyone will agree to fix it with the hole being in the board).

I should also include: I went to rockauto to see if they had a replacement, they had BlueStreaks BSE EM8359 listed, but unavailable. Within the information part of the item, it says "OEM / Interchange Numbers: F4TF12A650CFA, F4TZ12A650CFA, F4TZ12A650CFB." Is the ECM in my truck a replacement that someone had swapped in at some point? Am I ok to order one of these ECM's through someone like Flagship 1, or whoever has it, and feel confident that it'll work?

 

Oohh!! Exciting! I have only read about the code in these.
Yes, a unicorn indeed. The uniqueness of this one, being 7.0/429 is that it as code for a governor that is enabled.
If you use that, then you will need that. If not, then I would assume that a 460/7.5 'should' work, but might not have the hardware to run the governor.

Can you post a picture of the inside of the board please?

 

hmmm. Truck history: Viacom comms truck in California, so it makes sense a governor would be installed. I personally wouldn't take this thing over 55 mph out of fear, so I wouldn't need the governor to be enabled...
This is what was staring at me when I opened it up after getting it back from CCE. I can get more/other photo if needed.

 

What is CCE?
pm me, I may have a fix for you.

 

Car Computer Exchange, CCE, was who I had sent it to originally to see if they could repair it. I hope the fix is not to carb swap it

 

Did they say they couldn't fix it?? and sent it back?
Looks fixable to me.

 

They sent "non-repairable, unit has major damage to board from blown caps, cannot repair." So either they couldnt, didnt want to, or didnt want the hassle I figure. I'm still 9 days away from being able to send PM's so if you'd want to wait until then instead of replying back and forth on this thread, I am ok with that. Or I'll gladly keep working through it here.

 

I've made it through the post and time constraint to send PM's. Messenger states that you have elected to not receive private messages. I'm interested in reading about your idea for a fix. Not sure if you want to post it here or if you can PM me instead? Thank you

 

That's what I thought, over here. However, I don't think that ECM just got tired and burned a hole in its resinboard. I think it's likely that some system it is controlling developed a short or low resistance path (burned solenoid coil?) that took it out. I would not want to spend $$$ on a repaired or replacement ECM and just slap it in there and turn the key, without having tested each current path for low resistance.

Now, if I had a cheap hardware-similar ECM that I could consider disposable, as a test only, maybe a parts swap is reasonable. But OP was quoted $1800 for a replacement ECM, that later turned out to be NLA, and I wouldn't want to risk an $1800 part without doing some circuit checking on the vehicle.

Armed with an ECM-to-vehicle pinout diagram, it might be possible to pin down which circuit was tied to the area of damage in the ECM. I have considerable board-level repair experience -- not with ECMs -- but I have also encountered this situation, where I repair a board and then it burns up the same way when re-installed.

I haven't run a '79-on MD truck, but on the '78 and earlier, it's not a speed governor, it's a RPM governor. Ford had governors on all their Medium Duty trucks for decades. In the case of the FT engines ('64-78) the engines held up well if not run above 4,000 RPM, or for very long above ~3700, but would crack pistons if those limit are exceeded, and Ford installed either a Velocity Governor (on the smaller/lighter engines with the Ford/Autolite carbs) or Vacuum Governor (on the larger/heavier engines with Holley 2V & 4V carbs) through 1978. I do not know the RPM/longevity situation with the 370/429 as installed in the MD trucks or what the RPM limit is set to for them.

For example, while the block is the same on the FE and FT engines, almost nothing else is. All the but the cheapest 330 MD FT got forged crankshafts. Intake & exhaust manifolds are different and have an exhaust crossover passage not compatible with FE parts. The FTs are generally low compression, 7.1:1 and the pistons are much heavier than an FE's. They don't breathe, they don't rev, and run reliably for a very long time if kept from over-revving. On the outside, a 330/359/361/389/391 FT looks just like an FE, but almost nothing interchanges except the block.

In '79, Ford moved to electronic governors with the 370/429 engines in the MD trucks. The factory Holley carb got a solenoid (?) activated control for the vacuum pot, instead of a vacuum signal from a flyweight governor in the base of the distributor.

IDK what governor throttle mechanism the later FI models use.