That's sort of what I thought happened. I think I screwed up our message somehow. I never received it in my inbox. Thanks for taking a stab at it. For anyone following this thread for whatever reason Brian pretty much confirmed my initial thoughts about the daughterboard MS3 CPU being shot. It's in Peter's magic CPU fixing hands now.

you know....

i thought i recognized that BMW.

Turns out the answer to the title of this thread is throw money at Peter Florance. The ECU is up and working with my JimStim. I've got just enough working parts to be dangerous. It was what I was suspecting from the beginning, a bad MS3 daughterboard. Thanks Brian for checking it out too! :eek5:
https://cimg5.ibsrv.net/gimg/www.mia...a40dde4d05.png

how much money was thrown?

One Benjamin Franklin and another Ulysses S. Grant. :burncash: Considering a new MS3 daughterboard is $230 and I had no way of knowing rather or not it would be fried the instant I installed it, I consider it money well spent. I for sure learned a lot diagnosing it in the initial part of this thread. There was a lot of research before I even thought about posting, so I found a lot of good info I'll store in the good-to-know section of my brain. I'm finishing up my harness now and might even do some sort of build thread since I'm slapping my Garrett T25 SR20 churbo on it soon. Managed to score my friend's complete stock 2.5" Focus ST exhaust that I'm going to persuade to crawl under the Miata. Hopefully I'll be driving Megasquirt-ed within the next few days.

Didn't see the initial thread, but I did the same thing like summer - threw money at peter, got back a working MS some time later. peter is good people. just keep on him, hes usually pretty busy.

Well, I figured maybe having an MS3X that can connect to TunerStudio would be enough for me to handle the rest on my own, but that would be too easy :bang: I finished my harness based on the Trubokitty guides and tuned my pots (3 times for a sanity check)
I can't get a crank signal. It runs great with the stock ECU with the only check engine lights being emissions related. I thought maybe my CPS was out of whack and needed adjusting so I adjusted it within spec (it wasn't that bad originally) I know the MS3X can see a crank signal with my JimStim, but nothing with it connected to the car. When it's in the car the composite logger shows "Empty read, No Data Received from Controller" I've gone over the harness a few times and am fairly confident everything is correct. It powers up and sees the majority of my sensors just fine. I've taken both composite logs (no data though) and normal logs through the SD card. I'm running matching firmware 1.4.1 and the base tune from trubokitty for my car (01-05)

Here is a link to my tune/ logs: https://drive.google.com/open?id=1zW...L0BJDSn0HzKZXq

Any ideas?

I found a few things I thought might help but still having the same issue (no crank/ RPM/ "Empty read, No Data Received from Controller")
I re-adjusted all 3 pots as per trubokitty guide-

"Turn R56 (12) turns to the fully counterclockwise, then turn it back 7½ turns clockwise."
---
"Turn both R11 & R32 (6) turns to the fully counterclockwise. Turn R11 back 3½ turns clockwise. Do not turn R32 clockwise."

Is it possible I could have some mid-year shift with it being a 2003? I know the guides show 2001-2002 are slightly different wiring:
https://cimg8.ibsrv.net/gimg/www.mia...3df1c5202e.png2003-2005
https://cimg2.ibsrv.net/gimg/www.mia...9b39c6eaf3.png2001-2002


Below is my most up to date tune/ data logs: (is there a way we can post files directly in a port other than pictures?)

https://drive.google.com/open?id=1F0...QT4qZfdK1LOunH

Check your oe harness against those.

Would there be any obvious differences? I see there's several unused connections that I'm sure have to do with the immobilizer and other things the MS3X doesn't use. It could be either one if every wire is populated in the connector.
https://cimg8.ibsrv.net/gimg/www.mia...b7e5d46721.jpg
https://cimg9.ibsrv.net/gimg/www.mia...f3875118a4.jpg
https://cimg0.ibsrv.net/gimg/www.mia...3acaef6072.jpg
https://cimg1.ibsrv.net/gimg/www.mia...aa2112931b.jpg

main thing is if power comes in on 4AF or if on 4S then you need to activate the main relay on 3H.

hard to tell but it looks like your W/R wire is on 4S.

Yup, 4S gets 12V like it's supposed to. I guess that rules out it being a 2001-2002 harness.

so my docs aren't very clear on 03-05, but you need an output to active the main relay on 3H -- without that output, the majority of the engine bay is unpowered. do you have this wired up?

All I have wired up is from following the pinout on the trubokitty website for 03-05. How is this output wired?

Sorry, I think I found where you've answered this before. https://www.miataturbo.net/megasquir...pin-4af-94001/

That's for an 05 MSM though, so confirmation would be neat. Would I only need to have "Inj E controlling the main relay." or also have "Boost controlling the charge light"

I'd assume I need to have these custom ("key maps" comes to mind) added to my tune somehow. Still have yet to mess with TunerStudio on a running car so I'm fairly new.

Msm is very similar wiring, just no vvt.

If you notice I have it going back to the mainboard. Because the x is filled up, you need to either sacrifice the cell, or use an LED circuit. But you can't use those if you have knock module.

Forgive my ignorance but why couldn't I just jumper 4S to 3H directly? Doesn't the main relay just need power with key on? If it's just the signal wire to the relay amperage shouldn't be an issue should it?

That's not how relays work. It needs a ground to activate...

Now before you say, why don't I just wire it to ground, the answer is: because you like charged batteries.

Going back to your original answer "you need an output to active the main relay on 3H" Are you talking a physically different connection? Or just a configuration difference in TunerStudio? If it's just a setting in TunerStudio I need to know what and how to change it. Sorry for all the questions but I really appreciate your help.