E28 Megasquirt FAQ

Discussion pertaining to positive pressure E28s.
alijonny
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Post by alijonny »

heyyy, quick question as I can't seem to find it when searched. my tachometer on the dash isn't working, what do I need to wire up to make the tach work like stock (with my MS of course)?
Xenocide
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Location: Atlanta, GA

Post by Xenocide »

Are you running wasted spark? If so it's a slightly more complex setup, you'll have to build a small circuit in the proto area, but if you're just running a single coil you can trigger it off of the negative terminal of the coil.
more info here
Scottinva
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Post by Scottinva »

You need to put a wire between two pins on the ms connector.
Last edited by Scottinva on Mar 14, 2010 2:56 PM, edited 1 time in total.
alijonny
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Post by alijonny »

no, just standard spark at this point.
also, here's a low quality video of my car after a short run around the block.
I forgot what I have set for a tune, but I'm sure I monkeyed with something a bunch of months back. Time to throw down again.


http://www.facebook.com/#!/video/video. ... 913&ref=mf
bornagain
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Post by bornagain »

i tried using the zenor diodes on the spark outputs of the coil packs and it doesnt work so the next attempt is to go the way of brad and jumper and use spark output.
FirstFives Dictator
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Post by FirstFives Dictator »

alijonny wrote:no, just standard spark at this point.
also, here's a low quality video of my car after a short run around the block.
I forgot what I have set for a tune, but I'm sure I monkeyed with something a bunch of months back. Time to throw down again.


http://www.facebook.com/#!/video/video. ... 913&ref=mf
Did I hook up your tach when I had the board?
If so, I probably used IAC1 as tacho output.
Lurker27
Posts: 207
Joined: Feb 10, 2009 9:21 PM

Had a big problem this weekend...thoughts?

Post by Lurker27 »

Engine is a stock M30B35, automatic harness (variable TPS)

Megasquirt is a MS2 3.57, running 3.0.3.r. No jumpers or modifications made at all. (I can post the MSQ later but I don't think settings are the problem?)

Adapter is the most recent goathumper / diyautotune board, built by RS4pro. It has a female db37 so it can abut directly to the MS Unit

Megastim is V2.2 with the 12v AC adapter




Last weekend, i tried to follow the directions on the 55 pin motronic control board with regards to wiring the O2, and I messed it up. I tried to match the female end of the O2 plug, rather than the back end (which is how it is drawn, though this is not said. I realized my mistake when I checked the EWD later on). +12v and signal were wired to ground wires on my wideband controller, and the ground wires were wired to +12v and signal. (direct shortage going on). THE MS Box was NOT attached for this.

so...I fried Q4 on my adapter board, but I believe that's all I fried from a visual inspection of the adapter board. I resoldered a NPN2222A that match the digikey parts list (luckily radioshack carries these).



I used the megastim to flash my homebuilt msq, and took the assembly out to the car. I should note at this point that I noticed my MegaStim unit was not totally functioning...I could not use the RPM dial to change the gauge cluster on the dashboard. The indicator lights for PMP and IDL were illuminated, but it wasn't showing any ignition. MAP seemed to read correctly (100.0-100.4 fluctuating), and I was able to successfully burn settings. Everything reads back correctly to me when I talk to the unit with the megastim as power supply. TPS Seems to read fine. CLT reads fine. IAT reads fine.



At the car, I got cranking, but no fuel pressure. When I went to connect to the MS unit, I got NO COMMUNICATION...I made extra sure the connection from the USB to serial device was OK< since that's so finicky, but communication always failed. Went back to the megastim power source, works fine (but still gets no RPM signal. This is with the key in position 2 (on but not cranking). With the key in position 2, I see the 3 red lights on the megasquirt board itself...i only see these when i first plug in megastim. I'm not sure what they indicate, but it definitely won't talk to the laptop in the car.




Any thoughts? I feel like I burned something on the MS board that picks up RPM data, preventing it from tripping the fuel pump? I couldn't trace where Q4 on the 55 pin adapter goes, does someone have the circuit diagram (I could figure it from there)...Or my megastim rpm circuit is busted but that seems unliekly.


I have no idea why it doesn't want to talk to the laptop when hooked up to the 55pin adapter, but i think those red lights have something to do with it: Is this right:

A nice feature on the MegaSquirt® controller not found on other systems are three indicator LEDs which reflect the current operating mode of the controller. The first LED pulses whenever there is an injection event, and the glow duration follows the actual injector pulse width. The second LED is active whenever the ECU is in a warmup enrichment state (i.e not at 100%). The third LED indicates an acceleration enrichment, and is active during the entire duration of the event. Extremely useful, especially during installation and debug. Flashing lights also look "cool", particularly when you show off your controller to others.
Xenocide
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Post by Xenocide »

If you're just using the standard stimulator, you won't be able to see an RPM under the "Toothed Wheel" ignition setting. Switch it to "Basic Trigger," reburn your tune, power cycle MS, then put it back on the stim and see if you get an RPM.

There's no good reason for it to connect outside the car, but not inside the car. Double check your serial connections and adapter to be sure they haven't been pulled out.
Lurker27
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Post by Lurker27 »

The three red LEDs indicate that I'm getting low power through the adapter board - I'm going to piecemeal some other stuff together and see what I can do. Anyone have any experience with that board?

http://www.diyautotune.com/catalog/bmw- ... p-194.html
bornagain
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Post by bornagain »

nope no experience with the board but multi meter is your friend here.
Lurker27
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Post by Lurker27 »

OK wtf


I tried 2 more transistors in that position, and 1 of them gave the same error, and 1 visually blew out, again. I assume the other just blew internally without showing itself?

This means the O2 wiring has nothing to do with the blowout.



I traced the 3 pins from the transistor to the Motoronic pins they correspond to.

The middle (base) pin goes to the ignition switch pin (Motronic pin 27)

One pin appears to be unconnected to anything?

The other pin, in tracing the board, clearly connects to both Motronic pins 18 and 36


According to this http://img.photobucket.com/albums/v102/ ... nout-1.jpg

Pin 18 is Power, +12v from battery, and pin 36 is the ground on the main relay. WTF,


WHY ARE POWER AND GROUND CONNECTED TO THE SAME LEG OF THIS TRANSISTOR???

Furthermore, I don't know if the transistor is in the proper orientation. I have the 0.05 board, and am using 2N4401-ND....the site has this note:

Quote:
"* Part number PN2222AD26ZCT-ND also works, but must be installed in a reversed orientation on V0.03 boards. This was fixed on V0.05 boards, but then the 2N4401 must be installed in reversed orientation."


Should these pieces be lined up with the white masking, or shouldn't they? The way i read this, it looks like it shouldn't be, which means the guy I paid to build this board (mistake) screwed up. He claims he tested on a Jimstim with a 55 pin connector, but I have a feeling that that only has a limited range of inputs and fell outside the range of this problem. Even then, I feel like the pins to that don't make any sense.

PIC REQUEST: IS ANYONE RUNNING THIS BOARD THAT CAN TAKE A PICTURE OF THE COMPONENTS INSTALLED SO I CAN BE SURE THIS IS MY PROBLEM?

The entire range of support documentation for this board is a complete abomination. 100 out of 100 times in the future I'll be using the GG idle board and a homebuilt adapter.
bornagain
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Location: Edmonton AB

Post by bornagain »

first off, why dont you just nix the adapter and gut a ecu connector and get yourself a gg board and save face now. From the sounds of it your ms unit is working perfectly fine. If you are using the megastim board i dont believe it can be configured to show a tach signal for the toothed wheel setup. Another note that should be mentioned to maybe save you some time trouble shooting if you havent already done so, with the 3.57 board it doesnt like the 60-2 wheel and either the board needs to be modified (ask peter) or you need to install a 1-2k ohm resistor inline with the signal from the VR.

As far as the adapter board goes, if you dont know the orientation of the Q4 transistor that you are installing you are going to have to figure out the collector base and emitor of the specific part you have and solder it in that way.

To me it sounds like you arent getting ignition source power when you are cycling the keys, hence the no fuel pump and no connection. You should check to see if you are actually getting power(sufficient power) at the adapter board when the keys are cycled, you could also jumper the main relay(run power over to signal wire on the relay to turn on) and see if your fuel pump runs and your ms unit can be connected too.

Im not sure if it applies to your board but in my experience if you turn your keys to the on/run position and all three lights come on there is something wrong with the firmware. Try re-installing the Q4 in the correct orientation and figure out, before connecting anything, whether you have power or ground at 36 and whether your adapter board is supposed to have power or ground at 36 (37 is the pin you should be using to power your ms unit) then reflash your firmware back on your ms unit, and make sure its the right stuff for your adapter board. ohh and make sure your O2 sensor is connected right. Then try it.

Are you running wasted or distributor pick up? if you are running wasted, im not sure of this(V3.57), but, i dont believe the led's will correspond to the same things as the distrubutor setup. If its the dist setup then one is ign event, one fuel pmp and one for accel enrich. If that is your setup the f/pmp led will cycle for 2 seconds when power is turned on, whether or not you have an rpm signal. Ohh there is also one wire (my setup is probably not the same as yours, but) under the dash in the same connector that has the tach signal in the same connector ass swell and it signals the main relay to turn on. The connector is a flat 6 pin connector.(it maybe easy to trace if it has the tach signal coming fron it spliced to the coin wire output like mine) Like i said yours probably doesnt have it, as my car is an 83 533i, but with that disconnected my car will crank but thats it, its kinda a nice feature i used for priming oil after oil changes and head replacements.

I hope a bit of what i put down will help not just confuse.

to simplifiy what i would do.

resolder Q4
verify power and grounds and O2
Flash firmware
check for power at main with key on
check for 6 pin connector, verify connected
And try to connect to it with car power and ignition on. If you can connect then try to start if you are ready for that.

steve
Lurker27
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Post by Lurker27 »

Steve,

I've come to the same conclusions - If the Q4 was backwards (I just soldered a new one in and it didnt blow up in the reversed orientation), then Q1-Q5 are as well. Soldering a 55 pin adapter and a MS harness now.


In other words, I've been screwed over!


I'll reflash firmware, its a good idea....but it works just peachy on the stimulator power source. Reads TPS/IAT/CLT, everything but RPM (not a jimstim)


I'll also check some of the other Q1-Q5 to trace those leads and figure out if they are in reverse orientation.



Thank you very much for taking time out of your day to help me.
bornagain
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Post by bornagain »

yes but are the other four transistors the same number or are they the original that are meant to go in the correct way?

the other thing im wondering is if you 55-pin motronic setup is the same pin out as this board is using, is the motronic you have for an e34 or late model e28? the adapter board should be labeled for what pin is for what, no? if that is the case and you have it all the way the board is oriented then maybe something is pinned out wrong or maybe you have a solder bridge somewhere you are missing, lastly MAKE SURE all your diodes are in the proper way, i managed to wreck my fuel injection curcuit with an improperly directioned diode, to this day im still running one bank injection, cause i havent gotten around to changing out the necessary parts.

really i think you have something powering something that shouldnt recieve power and that is where the issue is, how its getting there can be a few ways as mentioned above, also check to make sure everything else in the same curcuit hasnt gone fubar on you either.
Lurker27
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Post by Lurker27 »

The documentation suggests they should all be reversed (all the same part #)....I think it's just assembled plain wrong.

Checking my EWDs....everything looks OK for the adapter I wired up as described in the first post. I don't need the motronic still connected for that, I take it?
bornagain
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Post by bornagain »

no you wont need the motronic wired up for that, but it made mention on diy that the pin out was changed somewhere in 86-87 for the 55pin motronic, but again im not super familiar with when they brought it in and if there were any changes made with it.
Lurker27
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Post by Lurker27 »

Checked out my EWDs, it seems to work fine. Soldering up an adapter really wasn't that bad.

Car cranks and "catches", but doesn't idle.....probably because my idle valve is not hooked up yet - everything look OK here in terms of noise and behavior?


My WBO2 should read from 10-20, not sure what the deal is there (may not have been warmed up, it is a NAW 7s controller.



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bornagain
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Post by bornagain »

i am trying to remember as i have recently rewired my car and now my afr reading in TS is all screwy where did you guys ground out your WBO2 sensors in the wiring harness. There are still a few other things i want to change in the wiring i have going on but i will get to that when i have this answer. Right now i would be happy having it reading .2 afr difference like before but the way it is, its absolutly unusable in TS. Dash is fin though.
Lurker27
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Post by Lurker27 »

I tied the grounds from the NAW unit to the 2 O2 grounds in the harness. If it also had a ground int he motronic connector, I've tied that in with the rest. The crank RPM signal ground is tied in there too, but I didn't see too much noise in the signals, but I'm worried about offset now.


I'll probably get some spades and start handing out new chassis grounds.
shamshoum
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Joined: Apr 05, 2009 3:02 PM

Post by shamshoum »

Sorry guys -it isn't related directly, does table bellow realy suit a forced induction M30??

Image
jcbe34
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Post by jcbe34 »

Didnt want to start a new thread for this, but I need some help. I bought a PnP ms2v3 unit from a member of the forums a while back. Tonight I began wiring my glens garage board to my MS and I came across this at pin 22/23. Pin 22 is supposed to be ISV2 from the Glens board (ICV closed) and Pin 23 shows o2 sensor relay. The jumper wire goes to pin 11 (GND) on the DB37 and looks to be accidently bridged between 22 and 23 but I don't think it should be there at all. Should I just put the wire to ground somewhere on the motronic connector?

Picture:
Image
Good & Tight
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Post by Good & Tight »

anyone want to share their accel enrichment settings or explain how to set them up?
I want to run 100% map but can't figure out the settings to get it run smooth. For now i'm running tps with the base values and it runs good.
Scottinva
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Post by Scottinva »

Good & Tight wrote:anyone want to share their accel enrichment settings or explain how to set them up?
I want to run 100% map but can't figure out the settings to get it run smooth. For now i'm running tps with the base values and it runs good.
If you wouldn't mind posting your msq on here or send it to me I could take a look. Is there a specific reason you want to run full MAP for AE? Could you post a log as well, to try to see what is going on?

I have good luck with full TPS and EAE.
Good & Tight
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Post by Good & Tight »

Scottinva wrote:
Good & Tight wrote:anyone want to share their accel enrichment settings or explain how to set them up?
I want to run 100% map but can't figure out the settings to get it run smooth. For now i'm running tps with the base values and it runs good.
If you wouldn't mind posting your msq on here or send it to me I could take a look. Is there a specific reason you want to run full MAP for AE? Could you post a log as well, to try to see what is going on?

I have good luck with full TPS and EAE.
Thanks for the tips on setting AE, I got it running 50/50 MAP/TPS and throttle response is very crisp and it got rid of the missfires. what do you think..?
Cant figure out how to load a datalog but here is a screen shot, and spark map.

Image

Image
Brad D.
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Post by Brad D. »

Man, that is impressive how much more timing can be run when you're running e85.
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