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Any info on an old MegaScott EECIV-MS adapter board (V1.21)?
#1

Hey all.

I have an old (bare) MegaScott EECIV to MS adapter board and am thinking I might try and use it, if I can find any info on it. 

I have a BOM for it, but no other instructions or documentation.

Thanks!
"Nobody can be so amusingly arrogant as a young man who has just discovered an old idea and thinks it is his own."

1983 TBird TC Clone  - 1985 Mercury Marquis LTS - 1986 LTD Wagon
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#2

Well, I was able to find a little bit of info, but I don't think I'm going to use it.
"Nobody can be so amusingly arrogant as a young man who has just discovered an old idea and thinks it is his own."

1983 TBird TC Clone  - 1985 Mercury Marquis LTS - 1986 LTD Wagon
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#3

Just saw this, although the reply is a little late maybe this will help someone else too.
I believe Scott's adapter PCBs were sold through DIY autotune from what he said here.
That said...I did make quite a few EEC-IV boards for sale off my original, now defunct MegaEFI.com web site, which BTW, that old board is still sold by DIYAutotune.com, though now foreshadowed by an "PNP" kit which they have developed in house.
https://www.msextra.com/forums/viewtopic...66#p279566

So these links should be correct for the documentation.
Settings
https://www.diyautotune.com/support/tech...rd-eec-iv/
BOM and assembly
https://www.diyautotune.com/support/tech...ter-board/
Schematic
https://www.diyautotune.com/wp-content/u...V20sch.pdf

Having bought the EEC-IV adapter board through DIY and used it for many years with MS1,2, and 3 it does work but also has one main defect in my opinion.
There is no main power protection on the the adapter PCB. 
Inside the megasquirt at least the V2.2 and V3.0 PCB there is also no main power protection, they intend it to be in the vehicle harness and recommend a 3A fuse for the MS box alone. There is a polyfuse on the MS PCB but this is after the main voltage regulator and only protects the 5V bus.
In the xr4ti and likely the other TF's there is a fusible link for the ECU main power and not a fuse.
All the other injector power, sensors, Idle Valve, etc are fed from the EEC relay after the fusible link.
This means that with the MS and EECIV adapter pcb in its stock form there is no power protection other than the fusible link, not good!
12V power is sent from pins 37 and 57 on the eec-IV connector directly to the MS DB37 pin 28, 12V input.
If anything goes wrong inside the MS or adapter board you will have a smoke show.
This could also be the case for some of the later DIY EEC-IV breakout boxes since the PCB shows no fusing provisions but I cannot comment directly on those.
Mine shorted some tantalum caps, which is a known issue, in the MS2 and in turn cooked the MS2 PCB beyond repair.
Just go over to MSextra forums and search C14 and read through the many sad stories.
Mine was just a normal startup, no charger connected or anything just turned the key and poof.
When that happened I started digging into the wiring/schematics and thats when I found this little nugget. Recommended fusing is also not mentioned at all in the DIY articles linked above.
So if anyone uses one of these or has it in their vehicle now I highly recommend adding a fuse for the megasquirt, somewhere....
After the magic smoke escaped from my MS2 I modified my setup internal to the EEC-IV adapter case so that is has that fused protection before it hits any of the MS adapter circuits or the MS ecu itself.
On my next megasquirt I also opted not to use those tantalum capacitors in the main PCB build.
If you don't want to modify the adapter board you should cut the factory wires after the eec relay and add a fuse into the car harness.
Jeremy
1988 XR4Ti Chestnut: Cossie 4x4intercooler, SVT brake upgrade, SVT rims, MS2extra, Deka 80LB HiZ injectors, Holset HY35
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#4

Yeah, I found all of that info previously, but I wasn't set on using it, as I wasn't sure I wanted the additional futzing with an adapter cable, etc.

Basically I'm looking to dump and old EEC4 ECU for a MS and do a multiport injection in place of a TBI for a project. Not looking for "power" just a drivability update to let me tolerate the car in its current state. (A quick turnaround thing)

Good note about the fusing. My previous installs have either used the relay box or I built my own power/relay set-up, so the ECUs were protected.

Honestly, I'm still up in the air on using this thing. I don't want to get too deep in it, but a drivetrain upgrade is off in the future, behind other projects and I don't want to dump too much time in trying to sort the crappy stock TBI system in the LTS. The car gets driven on the regular, and I'd like it's manners to be a bit better.
"Nobody can be so amusingly arrogant as a young man who has just discovered an old idea and thinks it is his own."

1983 TBird TC Clone  - 1985 Mercury Marquis LTS - 1986 LTD Wagon
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#5

So, I decided to use it. It's actually going to make my conversion pretty easy, when it comes down to it.

[Image: MSsetup.jpg]

I'm taking the above notes about circuit protection and plan on installing a fuse to the power circuit of the MS unit.

Also, not that it probably matters to anyone, but the BOM above has 2 incorrect resistors. The 10K and 10M Ohm resistors are supposed to be 1/4W units, but the part numbers are 1/6W. I missed that when I ordered my stuff.

Just need to build the interconnection cable now and wait for the time to get the swap done.
"Nobody can be so amusingly arrogant as a young man who has just discovered an old idea and thinks it is his own."

1983 TBird TC Clone  - 1985 Mercury Marquis LTS - 1986 LTD Wagon
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#6

That's a classic MS1 right there. If I were you I would ditch the tantalum filter caps or at the very least go 3-4x over voltage on the ratings if your dead set on leaving the tantalums. The newer type solid polymer electrolytic units would be what I would use if building one now but just some decent Aluminum Electrolytic caps are a safer bet then those little yellow smoke machines.
It looks like you have the FTDI USB-DB9 connector in there too, thats a nice addition.
Jeremy
1988 XR4Ti Chestnut: Cossie 4x4intercooler, SVT brake upgrade, SVT rims, MS2extra, Deka 80LB HiZ injectors, Holset HY35
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#7

That is the same vintage of MS that I've been running in the TBird since '06. I did the FTDI USB-DB9 conversion on that one too when I got tired of my in-line serial to USB adapter constantly giving me fits.

I'm not dead set on the tantalum capacitors, but are you talking about all of them, or certain ones in particular?
"Nobody can be so amusingly arrogant as a young man who has just discovered an old idea and thinks it is his own."

1983 TBird TC Clone  - 1985 Mercury Marquis LTS - 1986 LTD Wagon
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#8

The ones that filter the main supply is what I would be concerned about. The capacitors on the unregulated input have the highest probability for failure.
C30(4.7uf) and C15(33uf) are the ones on the V1 and V2.2 pcb, which it looks like you have. Be aware the BOM also shows 22uf on C15 and the schematics show 33uf.
The 4.7, 22/33uf ones can be replaced with electrolytic.
I went ahead and replaced the units after the regulator as well. You can also see the changes in the schematics as they learned this. MOV was added in as well as a zener across C14 on the V3 pcb's. Yet this still continued to be an issue. I suspect in my case it was just a spike from the starter that caused it.
http://www.bgsoflex.com/v1/megasquirtShem_V1.01.pdf
http://www.bgsoflex.com/v22/megasquirt_ShemV2.2.pdf
The reference designators changed on the V3 pcb and the ones there are C14(4.7uf) and C16(33uf)
http://www.megamanual.com/ms2/pcb.htm
Jeremy
1988 XR4Ti Chestnut: Cossie 4x4intercooler, SVT brake upgrade, SVT rims, MS2extra, Deka 80LB HiZ injectors, Holset HY35
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#9

I guess I also didn't upload the finalized pic of the set-up with the circuit protection on power to the MS unit.

[Image: adapter_1.jpg]

That should handle the issues you were referring to earlier.

I do have a second MS V2.2 unit on the shelf I might look into the upgrades you're talking about. I appreciate the insight.
"Nobody can be so amusingly arrogant as a young man who has just discovered an old idea and thinks it is his own."

1983 TBird TC Clone  - 1985 Mercury Marquis LTS - 1986 LTD Wagon
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