MS1 V3 Assembly Issue/Question
 

Referencing step 69c in the mega manual, there should be at least 60k ohms resistance between the metal tab of Q9 and Q12 and the heat sink. I'm getting upper 30k ohms resistance and tried sanding the heat sink lightly but it didn't change my results. Of course I missed this last half of the step before soldering it (last half of the step was on the next page of my printout) so its kinda tough to do anything about this but what else can I do to increase resistance here?

I did use the mica insulator and heat sink compound btw.

Upper 30s sounds fine to me. The important thing here is that you don't have a short circuit between tab and ground.

Funny, I just pulled up the datasheets for the TIP125 from Fairchild, ON, and ST, and none of them indicate that the tab is electrically active.

Ok, i'll trust your expertise on that and wont mess with it.

Now on to a tricky solder bridge I made when accidentally soldering on Q20 :vash:

I assume you mean the big TIP120 that you're installing in place of Q20, and not the little 2N3904, right?

When it comes to solder blobs, it occurs to me that a lot of folks who are newish to soldering probably don't know about desoldering braid: http://www.radioshack.com/product/in...ductId=2062744 This stuff is nothing more than a little strip of finely-woven copper thread, coated with flux. When you've got a blob somewhere you need to get rid of, just lay the braid over the blob and press down with the iron. The solder is wicked up into the braid and you have a clean pad left behind. Just keep braid properly trimmed so you're always working with the very end of it, and it works miracles.

I thought the TIP120 went on Q4, not Q20...Megamanual says not to install anything in Q20 for PWM.

Also, I know all about desoldering braid but unfortunately, i cannot eliminate this bridge and it is seeming to me as if I have actually newbishly bent the little metal parts into eachother. I may be screwed at this point.

Whoops- my bad. Yup, the '120 replaces Q4. Q20 is the overcurrent protection clamp which needs to not be there when you're running PWM (which, by definition, will be sinking a lot more current than that circuit was originally designed to deal with.)

Since the Q20 spot is going to wind up unoccupied in the end, you could always just break the pads off the circuit board with a X-acto knife if you've really munged them up that badly.

Ahh, a breath of hope. I'll try that tomorrow...to many drinks tonight to continue working with hot/sharp things.

I have another question though as follows:

Step 75 in the manual says to jumper R39 if PWM but brain didn't indicate that in his writeup (or more likely, i missed it). Should I jumper this use the resistor?

Well, remember that Braineack's instruction were written for a parallel install. It sounds to me like you're doing a standalone install, or you wouldn't be worrying about the IAC mod at all.

In the original design, R39 is there to create a voltage drop for Q20 to activate on. It's the setpoint for the overcurrent detector. Since we're not concerned with this, R39 is removed and replaced with a jumper. No sense in creating needless heat by passing current through a resistor when we don't need to.

Amazing, an answer with back information as well. Thanks so much. And yes, i'm doing a standalone.

Then you want to focus on the MegaManual, and go here for the Miata-specific mods: http://diyautotune.com/tech_articles...azda_miata.htm One thing- that writeup says to use 1k resistors on the SparkOut mods- use something smaller, like 270 or 330 instead.

So I already installed the 1k resisters. Is it actually worth the trouble of desoldering them and switching to smaller resistors?

The only thing one needs to do when following my writeup, when doing a standalone install, is performing the idle control mod as shown in the mega manual. Everything else should be the same.

Thats what I thought too...then I hear this about using something less than the 1k resistors...just wondering if its actually worth desoldering the 1ks and putting in the smaller ones.

It'll run fine with the 1ks. I went with a smaller value as a sort of thought-experiment after an exchange with the guys at DIY. It makes the trigger signal much prettier (if you happen to be observing it on an oscilloscope) but seems to make no functional difference.

Haha...he said munged!:giggle:

See usage #2: http://www.catb.org/jargon/html/M/mung.html

I got it! I read your other post. I think I may start using it myself. I have a few things around here that are munged!

Can the TIP120 do without the mica insulator? It didn't come with one from DIY like the other things that attach to the heatsink (that require an insulator anyway).

Like I said in post #2, the TIP12x family datasheets do not indicate that the tab is electrically active, however it's almost always good practice to isolate metal-tabbed devices.

Well, excitingly enough its all together now and blinking away with the stim as it should be.

Thanks for the help, Joe! I'm sure i'll need more later on :)

Haha, a little encouragement goes a long way :)

Is it even worth the trouble to wire this thing into the car before I have my WB02? I dont have the turbo in yet either but i'm really anxious to see how this works in the car...

Ok, so last night I continued through Brains writeup and installed the software, changed the various settings etc. Stopped at the point of "now you need to load a basemap" because I was getting a little (too) drunk to be doing anymore of it.

Today, I plug in the stim and nothing is happening. Only light i get is the IDL light on the stim. Is this normal? Did I fuck something up or can I start over? I dont know what the fuck the problem is now...nothing appears to have come loose inside...

Edit - Somehow its working again...lights are blinking away. Even more confused.

Just a wild guess, but after configuring the wheel settings menu in Megatune, you'd at that point need to reconfigure the wheel simulator on your JimStim. (This is a JimStim, right? The one with the 8 DIP switches?)

Specifically, you need to run a physical jumper wire from the pin labeled "2ND TRIG" to the pin corresponding to where you've set up your CMP input (usually I1A) and then set switches 2 & 3 on.


http://img33.picoodle.com/img/img33/...Am_2a99468.gif


Looks like you snuck in there with your edit while I was marking up the picture.

Oh, to answer a question you asked earlier, I wouldn't bother running it in the car for any length of time without WBO2.

This isn't a Jimstim. Megastim v 2.21

Mkay, I have another question that is stumping me right now.

Like I said, I got through Brain's writeup to the point of "now you need to install a basemap" and stopped.

I went to open megatune and I have it twice now in the megasquirt programs menu. They both say megatune 2.25 but have different pull-down menus and the megasquirt only seems to work with one of them (the one I installed whilst going through the megamanual).

Should I have uninstalled everything the megamanual had me install before going through brain's guide?

Oh.

Well, you won't be able to test the MS in its "full" configuration. Set the wheel decoder back to single I guess. I'm not sure why MegaTune still allows you to set wasted-spark and alternating injection with only one, non-missing-tooth wheel.


Sounds like you've got two completely different installs of MegaTune going on right now. Before we rectify this, a question- have you already re-flashed the CPU with MSnS-Extra code? (you would have used EasyTherm to do this step, most likely.)

Yes, i remember doing something in easy therm. If memory serves me right, I changed some things, selected the "Custom" code version then hit the "Write to..." button. Is that what you're speaking of?

Ok, i think i'm getting more and more confused.

I flashed firmware again, looks like i'm running 029y3, is this the correct firmware? Should I be using HiRes firmware? I'm completely stock right now, i want to get this all working before I put turbo stuff in.

After flashing the firmware, the behavior of the lights on the front of the 'squirt changed. The middle light used to be the warmup enrichment light, now it doesn't change when I turn the CLT knob on my stim. It blinks with the first light when I turn the RPM knob. Is this due to the fact that I dont have a jimstim?

I have an LC-1 now to go in with this thing. I'll be wiring it (the ms) directly into the stock harness, not going to bother trying to buy the tyco connector. I think i'm pretty close to installing this thing, prolly this weekend. I just want to make sure all my ducks are in a row first.

BTW, this is a standalone install as a reminder. Anything I should be made aware of before I install this thing, like a checklist of sorts? Things to expect?

Asking "Should I run HR code?" is like asking "Would I enjoy having sex more frequently?"



The functionality of the LEDs (as well as other pins) is going to vary depending upon your inputs to the "Codebase and Outputs Function" screen:

http://img34.picoodle.com/img/img34/...sm_0bafba3.gif

In the above example, you can see that the middle LED is set to Output 4 (not warmup) and the first and third are set to be the two spark outputs.


Without a JimStim, you're not going to properly simulate a Miata CAS. For now, you could go back into the wheel decoder screen and disable the second input. That should at least get you reading RPM, though in trugh I have no idea how wasted-spark will respond to this.

I'm already getting an RPM reading so i'm not going to worry about that stuff til I get the thing installed.

I understand there is a decision to be made on HR code which is why i asked if I should or not. My logic tells me it isn't going to make a difference unless i get bigger injectors. Am I correct in this assumption?

So Firmware 029y3 is correct then? I remember reading an aussie post calling out some issues related to this firmware.

http://www.boostedmiata.com/MS/db37_MS_pinouts.jpg

What is this "shield" from pin 2 to pin 24? I'm trying to make sense of that while comparing it to the DB37 diagram in the mega manual. Am I just suppose to run a jumper wire between those pins or am I suppose to solder the shielding from the wire on pin 24 to pin 2?

Pins 1-2 and 7-19 are all grounds. So they're saying connect the shield from your input wire to pin 2. Odds are you don't even have a shield on the wire, so ignore this.

Run the High res code. It's the bandwagon everybody MS I is jumping on. Jump on with them if for no other reason than to have more people to get support from when you need help. '

http://www.megamanual.com/ms2/v3ext_wiring.gif

Thanks pat for the input on using hires code.

The wire I have running to pin 24 does have a shield on it. Should I still ignore it?

Pat's on the money. If you buy the wiring kit from DIY, then the wire labeled as being for the primary ignition input is shielded. This serves no useful purpose in the Miata, it's a holdover from the VR sensor. If using this wire, the shield of it needs to be connected to a ground. Doesn't matter specifically which one.

I suggest using a piece of regular unshielded wire for this connection, both to reduce clutter and since the center conductor of the piece DIY provides is too thin, IMO, for a good crimp on the other end.

Sorry for not answering the code question earlier. I advise HR10g, which can be gotten here: http://www.msextra.com/viewtopic.php?f=90&t=25336

Alright, sounds good. Thanks guys, will return with more questions shortly but atleast my DB37 connector is finished.

Oh, another question for those of you who wired the db37 directly into the car instead of using the tyco connector...

What crimp connectors did you use? In the past with alarm installs i've used T-Taps on the factory wires to get a connection. Should I use something better/more robust for these connections?

A small, token prize to the person who identifies all the different types of wiring devices that I used:

http://www.boostedmiata.com/MS/harness/direct_db37.jpg

By way of meekly defending this mess, I'll note that I'd previously had an EMU in here, so any wire which had previously been tapped or cut for that simply got re-used. There are a few connectors hanging with nothing plugged into them- those were connections made for the EMU that weren't needed with the MS.

I see butt connectors, a T-Tap, spade connectors (male and female) and I think a wiring nut? What is that box with the wires on top of your squirt?

Ok, i have seen that image, i think I'm going to just use T-taps, they are the easiest thing to use. I really hate trying to tame a clusterfuck of wires =P

Solder and heat shrink everything. Many will disagree with this, arguing that solder could crack over time. But in the real world, I see crimp connectors fail all the time and never see a soldered joint fail. When I built my MS2 standalone (read, more standalone than yours), I soldered everything.

Am I still going to be able to use the mspnp 9093 .msq with the HR code? Are all the settings the same for idle etc? I flashed it to the ms last night and I think I may take a stab at installing this shiz today.

Truthfully, I don't know if the actual MSQ itself will be portable from lorez to hirez (I never tried it) however the vast majority of the tables and settings will work just fine. Idle, spark, cranking, warmup, etc should all be 100% correct. In my experience, VE will require some slight tweaking, but I emphasize slight- well within MLV's capabilities.

Ok, my level of confusion is growing now that i'm on Hires.

My required fuel calculator is throwing me off as well as the constants page. It keeps changing back to a 350CID engine with 42lb/hr injector flow. What should my settings be on engine constants and req fuel?

I'll play. See how many types of connectors you see in my entire engine harness.

Attachment 210459

Attachment 210460


Answer: There's large butt connectors for the +12V wires where they go into the fuse holder. And a couple others. But 97% is soldered and heat shrinked.

Try opening Megatune, opening a known good MSQ, and then setting the constants you speak of, then close, then save. Reopen and see if they changes took effect.

The calculator has no bearing on actual operation. It's just a tool to help you figure out the correct value to put into Req_Fuel. And yes, it resets itself every time you close it.

The Req_Fuel constant should not change much when switching between regular and HR code. Thus, assuming stock injectors I'd keep it at the stock DIY setting. For your 1.6, that would be 13.4.

The same goes for the rest of the engine constants. Start with the DIY values. Unless you've changed the injectors already, any tweaks to the defaults will be minor for now.

http://img02.picoodle.com/img/img02/...sm_3772c4e.gif

I've changed all the settings to the DIY ones as outlined on their writeup. I've made sure my constants reflect the above. There still seem to be lots of menus with things that I haven't changed but i'll follow JP's advice and leave them be.

I guess i'm ready to start wiring things up. Brain's diagram of the Miata ECU harness with the callouts is only for paralell i assume. It seems to have several fewer callouts than wires that i'll need to splice in. What should I be following for wiring the pigtail into the stock harness?

Also, should I wire up the WB initially or get it to idle with the NB first before introducing too many questionmarks to the process? As for grounding, do I just run all the ground wires through the firewall to the valve cover directly?

Sorry, I didn't mean to imply that nothing else needs changing from a "bare" MSQ- lots of stuff in fact needs congifuring. Cranking, warmup / ASE, idle control (two pages' worth), some outputs, etc. What I am saying is that for starters, you can use the base maps (.MSQ file) that DIY distributes with the MSPNP: http://megasquirtpnp.com/mspnp_downloads.htm

Ideally, your own notes made while looking at a copy of the factory service manual's wiring diagram. :D

Assuming you built your MS essentially to Brainey's specs (in terms of pinout) then you can wire it the same way as he calls out. It doesn't matter, for instance, if you splice into a line rather than cutting said line if there's no ECU on the other end of the harness. Quite a few connections on my harness are tapped rather than cut, for no other reason than that they were tapped back when I had an EMU, and now it doesn't matter since the ECU is gone anyway.

The WBO2 should be installed and working before the MS goes in.

Yup.

Well, not the valve cover itself, but the main grounding point in the rear section of the head. (or is it the IM... I honestly can't remember where those bolts are...)

Ok, thats why I asked earlier if I could actually use the MSPNP .msq with the HR code. I'll give it a shot.

I started tapping into the wires last night following brain's callouts on the stock ECU pinout. Rather easy once I figured out which way to look at the harnesses =P. All I need to tap is fans and idle i think other than what he has on there.

I came to this conclusion last night. Logically in my mind I didn't think the LC1 would work with the stock ECU. After reading the documentation, i realize that my logic is flawed.

There is kinda a bracket (one of the ones used to hoist the engine) that actually attaches from the valve cover to the manifold for that ground. Thanks for clearing that up, thought it sounded kinda iffy tapping into the stock ecu grounds. I'll run all my grounds through a heavyish gauge amp power wire I have sitting around :)

Last question for awhile...

I wired up my fans mod like in the writeup, which pin is that going to come out of on the DB37?

Give the DIY MSQ a shot. I can't think of any reason why it would not work, I just can't say for certain that it will.

IAC2A is pin 29.