Thats how Y8s had his set up. Any disadvantage? Could this be causing my problem?

I am working off of Y8s pinouts and MSQ as a guide.

If you think this could fix the problem I will pull the connector apart AGAIN and adjust.

 

Ok, I just went ahead and took care of switching to injectors E and F for fan controls. Not sure if it did anything because car wasn't running long enough to get warm.

I did a drive around my subdivision (woo-hoo!) but the charging system light came on so I cut it short. I don't know why I wouldn't be charging, the stock computer is running the alternator supposedly - until I can build the alternator control circuit.

I will let the battery charge a few minutes, check my connections, and try again.

 

y8s had extra output circuits built on his mainboard using tip120s.

 

Per advice on another thread I installed the stock IAC sensor and battery seems to be charging. Just got done with about a 20 mile drive on autotune. Seems pretty solid.

Now for the bad:
A/C compressor won't turn off.
A/C switch on dash won't light up, switch doesn't work.
Cruise control doesn't work.
Can't go full throttle from a stop above 4300 rpm or so. I can however gradually go above 4500 rpm if I do it at half throttle or so. Any ideas?

 

It wasn't power steering fluid - it was A/C compressor oil. For some reason it vented. I am guessing this relates to my A/C compressor being constantly on. Lets fix that problem first...

While I had my Megasquirt out of the car early in the project... (Friday?) and I installed the Knock sensor unit from DIYautotune. I also notice that my A/C idleup was on the wrong input. I don't recall what it was, but it was incorrect.

I woke up this morning and saw that in my notes from Y8s, he had A/C idle up on JS11. I changed my MSQ to reflect that and tried to connect it up.

Maybe I don't have the knock sensor set up correctly, but tunerstudio warns me that there is a conflict between JS11 and my knock settings.

Confused. Hoping someone tells me what I am misssing while I work it out on my own.

 

JS11 may be standing in the way of everything working, but all that does is provide a ground and I unplugged the refrigerant switch (which should remove the ground) and it didn't solve my problem.

The problem has to be elsewhere...

 

Well, found the cause of my stinky problem. Smoke checked U4 trying to use the injector drivers to power fan controls.

Can I just pull U4 and leave it out for now?

 

I am very damn close to wanting to throw/destroy something. Lets work my way away from the big damn hammer...

Ok, AC [idleup output] was selected as [IAC2]. The way I understand it is this:

[idleup output] --> [IAC2A] = [IAC2] = JS2

Correct?

If so, then wtf is IAC2B?
[IAC2B] = JS3, but what does that correspond to in the inputs/outputs? Why can I not select IAC2A or 2B in the outputs? Only 2B is selectable, and that is only with the name IAC2...

The way my MS is currently wired:
IAC2B to JS3 - Purge Control. Y8s diagram has this as JS0
IAC2A to JS2 - AC idleup output
IAC1B to JS1 - MIL Light wired to it, but Y8s diagram had this to D15? Non functional at the moment. Confused...
IAC1A to JS0 - Not Used

Can anybody help me straighten this out?

 

Ok, here is my proposed solution.

JS11 is in use by my knock sensor so I can't choose that. JS5 is in use by my on board 2nd MAP. JS4 has been wired to IAC1A (A/C idleup IN). Any reason that wouldn't work?

M25 IAC1A to JS4 - A/C Pressure switch
M27 IAC1B to JS1 - Check Engine
M29 IAC2A to JS2 - A/C Switch
M31 IAC2B to JS10 - Purge Control

Is this ok/safe? Any safeguards, diodes, resistors I need to put in line?

Thanks!

 

Answer to the above question? Don't do it. Just smoked my EMS. Part out thread coming soon. (not sure if joking yet.)

Before starting car, turned on EMS. Hit AC button on dash, light lit up. Turned AC off.

Started car on Megasquirt... Ran fine. Hit AC button. Car died instantly. Cranked, no start. Pulled Megasquirt out of car, hooked up to stim. DEAD.

Time to start breaking stuff?

What did I likely kill? Anything I can replace or am I back to square one building a new MS3?

 

here's your problem:

you tried to build yours based on y8s' without building any of the additional input/output circuts (or research) y8s did.

all you inputs and outputs should be on your expander board with safegaurd to prevent flyback voltage from killing your ECU.



tl;dr: that a/c switch put 12v directly to your ms3 cpu and you fried it btw (youre not the first to do this, but without building in safegaurds on the input, it will do exactly this).

you need to send your daughterboard to Peter Florance along with ~$90 for him to replace the CPU and the canbus and reload the boot header and mail it back to you all fixed up.

In the meantime you need to demod your entire mainboard full of circuits and move the a/c in, a/c out, purge, check engine, knock, injectors, spark, EVERYTHING to the expander board.


what you should have done is follow an actual writeup: http://westfieldmx5.devocht.com/?s=99-05

 

Here is the problem though. I am not building a DIY style MS3, so I took parts of frank's write up and parts of the standard build and thought I had something that would work. I acknowledge that I am over my head, and that I should have probably just paid one of you guys to build me something that did what I wanted, but I wanted to learn. I also wanted to build a parallel system so I could keep my OBDII. I knew it was going to be hard, I knew I would likely hit roadblocks, and I knew I might fail and it would cost me a bunch of money. I know most of you all recommend against it.

Part of it is stubbornness. I started building the MS3x because I thought it would do everything I wanted it to do out of the box, and could be modded to do even more things. (knock, second MAP, etc) Once I go into the build and learned I did more than I needed to, and by this I mean I installed more on the board than I needed, I was reluctant to start desoldering stuff. Building custom circuits inside the box is not something I thought I would be doing. I wanted vanilla. It's getting to be crazy mint raspberry sherbet. Not sure how I feel about that yet.

Thanks for the advice. Aside from cost, what is the benefit of sending my board to Peter as opposed to just buying a new MS3 board?

Oh, and thanks for the help. I may be a bit upset right now, but its mostly aimed at myself.

 

but you are.

It didnt need to be, there was no reason to build any custom circuits in your case. possibly for the second map sensor, but again, that's another input on the expander already built I dont see why a parallel setup would be

~$90 is a hellofalot cheaper than $199...

 

Am I? I am preferring to stick with the DB37 connectors. I think I meant DIY PnP.


I don't believe I have any custom circuits aside from MAPdaddy and Knock. Are we talking about the jumpers from JS0 etc? Are you saying we can accomplish knock sensing without using the DIYautotune knock board?

I will post all of my jumpers etc when I get home and you can tell me if I am right. I thought I pulled them from reputable sources...

 

how about this: What ECU pin is going to JS4 and JS2?


yeah, you never built any of this.

 

Is this a rhetorical question? I would imagine that the ECU pin that corresponds to JS4 and JS2 doesn't change board to board, but then I don't know squat really. Neither JS4 or JS2 is jumped to anything on the MS3 board that isn't done through the normal risers, if that makes any sense?

From the JS2 or JS4 PAD I jumped to the IAC2A, etc as described in my previous post.

I could pull the MS schematic and tell you, but off the top of my head I have no idea.


If by "this" you mean I never built any of these safeguards, correct. I got impatient and thought I knew what I was doing.

Tonight when I get home, should I start by trying to retrofit back to match Frank's build?

 

How this jumper business started was when I followed the MSextra build guide...

I think when I built the MS3x, my thought was that I wanted to keep the extra programmable output, so I wired it the way they described in the above step. I initially built this box back in October of 2011, so my recollection of all my hows and whys are a little shady. I stopped working on the project when I realized I didn't have enough money to complete the turbo project, so there was no real benefit to megasquirting until I was six months out from being able to turbo, or so. And so it sat.

 

You know what I meant. your oem wiring/ECU connector pins.

You said you have JS4 jumped to IAC1A and JS2 jumped to IAC2A.

where do IAC1A and 1AC2A go on your harness? 4F and 2K?

post pics of your board.


I remember reading once someone else with an NB had this exact same issue with the A/C killing the CPU, I can't remember why exactly and I cant find the discussion. But you didn't put any active low circuits on JS4 which is dangerous, you also didn't put any output relay circuits on JS1, JS11, or JS4 did you?

That's what I'm trying to figure out.

 

no input/output circuits for AC = dead MS3.

I need to know the link you used to get the info to build your MS3 so I can correct it and prevent future builds from blowing their ****.

 

Y8s, you have been a big help - don't feel that the stuff you did to put me in the right direction caused this in any way. I didn't ask the right questions and assumed too much.

Here is the thread I used that gave me my initial AC information.

https://www.miataturbo.net/megasquir...01-05-a-69824/