MS2 V3.00 EDIS No tach signal on stim

[hummer010]

Alrighty, I'm building an MSII on a V3.00 Mainboard that is going to be setup for EDIS ignition. I'm using a Megastim V2.21 running on a computer power supply, which is delivering about 11.8V. If a 9V battery is good enough, this should be more than enough. I'm using MSII firmware 2.905 and running the latest version of TunerStudioMS (2.0.6) (Registered, not that it matters for this).

I've done all of the EDIS modifications:
I've jumpered IGN to JS10
I've jumpered TSEL to OPTOOUT
I've jumpered TACHSELECT to OPTOIN
I've jumpered XG1 to XG2
I've jumpered both D1 and D2
I've installed nothing in C12 and C30.

When I hook up the Stim to the board and the board to the computer, everything works except for the tach signal and the O2 signal. What I've read says the O2 signal will not work until there is a tach signal. I've gone over the solder's on the board and the stim, and everything looks OK. I'm no champ on the iron, but it all looks OK.

I followed the suggestion here which says:

This is a test I wrote for testing with just a volt meter:

With the Megasquirt powered up, apply 12 volts to pin 24 or TachSelect, and check the voltage on the TSEL jumper with a voltmeter. You should read zero volts. Next, ground pin 24 so it has no volts on the input circuit, and check TSEL's voltage again. You should see 5 volts there. Let me know what you find.

It could also be adapted to an oscilloscope with the same rules: 0 volts on the output when the input is energized, 5 volts when the input is grounded.

When I put 12v to pin 24, TSEL reads zero. When I ground pin 24, TSEL reads 5v, so that appears to be correct.

I'm running out of ideas what to look for. Anyone have anything I can look for to get the tach signal working from the stim? Is it something as simple as a setting in TunerStudio? I've got my "Coil Charging Scheme" set to "EDIS". Are there other settings in TunerStudio that I need to do for EDIS?

Thanks for any help.

[Matt Cramer]

Please post a copy of your tune file; I'd like to check the settings for RPM killers.

[hummer010]

Is this the right file?

I have another question. I'd like to do a bit of a phased install; fuel first, followed by ignition. Is it possible to install the the EDIS VR sensor and control box, and use that for the tach signal while still using the distributor to handle ignition. Then once I've got the fuel setup and running, and switch over to EDIS for ignition.

It just seems easier that way than having to re-solder the board to change from a points system to EDIS or having to get fuel and ignition setup at the same time.

[trakkies]

In TunerStudioMS, set:

Trigger offset = 0° (this will vary slightly, depending on the wheel/pickup configuration),
Ignition Input Capture to 'Rising Edge'
Cranking Trigger to 'Calculated',
Coil Charging Scheme to 'EDIS',
Spark Output to 'Going High (Inverted)'
Trigger Wheel Teeth to '0' (zero)

Set the predictor algorithm option to 'last interval'.


I'd say using the standalone distributor ignition system for sparks, while taking the tach signal from EDIS not a good idea. The only changes needed to MS hardware between EDIS and triggering from a coil is D1 and D2, which are needed for a tach signal from the coil. They can simply be bridged with wire links when you change to EDIS.

[hummer010]

In TunerStudioMS, set:

Trigger offset = 0° (this will vary slightly, depending on the wheel/pickup configuration),
Ignition Input Capture to 'Rising Edge'
Cranking Trigger to 'Calculated',
Coil Charging Scheme to 'EDIS',
Spark Output to 'Going High (Inverted)'
Trigger Wheel Teeth to '0' (zero)

Set the predictor algorithm option to 'last interval'.

Thanks, I haven't had a chance to test/check those settings yet.

I'd say using the standalone distributor ignition system for sparks, while taking the tach signal from EDIS not a good idea. The only changes needed to MS hardware between EDIS and triggering from a coil is D1 and D2, which are needed for a tach signal from the coil. They can simply be bridged with wire links when you change to EDIS.

I hadn't actually looked at the differences between the EDIS and the coil setup. It looks to actually be four components (D1,D2,C12,C30), which isn't as much as I had thought it was. I'll just build it up properly for coil triggering, and then make the switch to EDIS once I have the fuel side of things setup.

[hummer010]

OK. Still working on this. I've made the modifications to trigger from the negative terminal of the coil. I'll set this up for fuel only right now. I added D1, C12, and C30. I haven't added D2 yet because it won't work with the stim. I will add D2 once I get ready to install it in the truck. However, I still can't get an ignition signal. I'm at a bit of a loss as to why. I'm not too sure what settings I need to change in tunerstudio to work as fuel-only, and to trigger from the negative terminal on the coil. I'll attach .msq again.

What are the two switches for on the stim? The ones that are right beside the RPM and O2 pots? Switching seems to do nothing.

Is there any way to test the stim? Could it not be putting out an ignition signal? I'm tempted to start wiring up the truck so I can see if I can get an ignition signal that way.

[hummer010]

I should have mentioned in my previous post, D2 is still jumpered. I just haven't add the Zener diode yet, because it won't work with the stim.

[Matt Cramer]

No settings jumped out at me. Let's test the opto input circuit. With the Megasquirt powered up, apply 12 volts to pin 24 or TachSelect, and check the voltage on the TSEL jumper with a voltmeter. You should read zero volts. Next, ground pin 24 so it has no volts on the input circuit, and check TSEL's voltage again. You should see 5 volts there. Let me know what you find.

[hummer010]

No settings jumped out at me. Let's test the opto input circuit. With the Megasquirt powered up, apply 12 volts to pin 24 or TachSelect, and check the voltage on the TSEL jumper with a voltmeter. You should read zero volts. Next, ground pin 24 so it has no volts on the input circuit, and check TSEL's voltage again. You should see 5 volts there. Let me know what you find.

I have already done that. Everything checked out right.

[Matt Cramer]

Sorry, missed that in the first post. You might want to try reloading the firmware and starting from the default map in case you have a corrupted tune file somehow.

[hummer010]

Sorry, missed that in the first post.

No problem. I went and checked it again last night just to be sure. It all checks out correctly.

You might want to try reloading the firmware and starting from the default map in case you have a corrupted tune file somehow.

Will do.

[hummer010]

Okay. I've updated to the latest MSII code - v2.920. It was a little painful. I generally run linux, but there's no Loader app for linux that I'm aware of, so reboot to windows and discover that my Prolific 2303 based USB->Serial adapter isn't support in Windows 8. Grrr. In the end, I had to bring it all to work and load it on the Windows 7 box at work. The plus side to this is that there is no previous versions of TunerStudio or my project, so everything was a fresh install.

Still no workey.

The first time I fired it up after the reload, the PMP light on the stim turned on for about one second, and then shut off. The IG light turned on and stayed on. The D14 LED on the MS board (Injector) lit up and stayed on. Every time I've fired it up since then, the stim acts the same (PMP for 1 second, IG on constantly), but the D14 LED on the MS board hasn't lit up since that first time. Weird.

I can't remember for sure if the IG LED was lighting up on the stim previous to the software reload, but I think if it was, I would have mentioned it in the original post.

The EGO gauge in Tunerstudio reports either 14.70 volts or 12.00 volts depending on what the pot is set to when I fire it up. It doesn't respond to the pot, but I don't think it is supposed to without an ignition signal. From what I remember, this is an indication that the O2 sensor input is working.

[hummer010]

I reflashed it again, and again. Every time it's the same results.

The first time I power it up after the flash, the IG LED on the stim stays on, and the D14 LED on the Main board stays on. Every subsequent boot after that, the D14 LED doesn't light up, but the IG still does.

[trakkies]

Is this with TS showing zero revs from the stim?

[hummer010]

Is this with TS showing zero revs from the stim?

Yup. And EGO shows either 14.70 volts or 12.00 volts depending on the switch and pot settings.

[Matt Cramer]

Exactly what Stim version do you have? V2.2 and later ones need the RPM switch set to "PNP".

[trakkies]

Exactly what Stim version do you have? V2.2 and later ones need the RPM switch set to "PNP".

As an aside, isn't it about time the manual was updated to include this version of the Stim?

[hummer010]

I have stim version 2.21. Is the switch your talking about the one right beside the RPM pot? If so, I've tried it in both positions with the same results.