I did a search and though this is a common problem, it's not 100% clear to me how to solve it.
I don't have an RPM read in TunerStudio, other sensor readings respond.

Per DIY, jumpers are soldered for TachSelect to VRIN and TSEL to VROUT. JP7 Jumper on MS3X is off.

My MS3 V3.0 board with MS3X is flashed with firmware 1.0.2 and the included ini.
Ignition options set are:
Spark Mode: Toothed Wheel
Ignition Input Capture: Rising Edge
Spark Output: Going High (Inverted)
Number of Coils: wasted spark
Spark hardware in use: MS3X spark
Cam input (if used): JS10
Trigger wheel arrangement: Dual wheel
Trigger wheel Teeth(teeth): 24
No missing teeth
Tooth #1 Angle (deg BTDC): 0.0
Main wheel speed: Cam wheel
Second trigger active on: Rising edge
and every rotation of: crank

JimStim is V2.0.3. JimStimX is also installed.

On the JimStim, 12V pullups are set, so is the the jumper for the VR Signal. Dip switch 5 is set to on.

Is there another jumper I'm supposed to use?

 

Here's what I have so far. The tables aren't in place and there's still a lot of work to do. I only finished assembly last night and did the final jumpers an hour ago. I'm strictly bench-testing the MS3/MS3X; actual installation isn't for a few months.

 

Have you tried adjusting r56? Iirc thats the pot for the Vr sensor filtering.

 

No, I haven't. Adjust how?

 

Are you just trying to get a rpm signal through the jimstim? I've found it easier to just wire up a spare Cas to the jimstim on the appropriate screw terminals and spin it by hand to verify rpm signal. As far as "tuning" the Vr conditioner pots you will wanna start with how it says in the megamanual (iirc fully counterclockwise) and while spinning the Cas by hand start turning them clockwise till you get a reading.

 

Okay. I did look up the that part of the manual after you suggested it. http://msextra.com/doc/ms3/ignition.html

There's also the two resistors on the MS3X board.

Unfortunately, I don't have a spare CAS handy. On the other hand, I could pull my CAS and try that.

 

Def would try that then. I never had good luck in my own experience with the Jim stim and rpm signal. Always just used a spare Cas wired up time jimstim.

 

Update:

I have RPMs! Here's what you need to do to configure your StimJim. This is assuming that you also did the following to the MS3 and X via Diyautotune:

Set up the ECU up to trigger from the VR Input. Jumper TachSelect to VRIN and TSEL to VROUT for a V3.0. For a V3.57, set the JP1 jumper on the main board to the 1-2 position, and set J1 to the 3-4 position.
Make sure the JP7 jumper on the MS3X is off, as you don't need the pullup on the second trigger.

Note: You will need to StimJimX card if you have the MS3X.

With the power off:
1. Jumper the pullups to 12V
2. Set the jumper for the Primary Tach to VR signal - shown here http://jbperf.com/JimStim/JimStim_v2...jumpers_vr.JPG
3. Plug in the StimJimX card and attach the following three leads:
a. 5V on the StimJim to 5V on the StimJimX
b. GND on the StimJim to GND on the StimJimX
c. 2nd Trigger to CAM pin on the StimJimX.

Power on and you should have an RPM reading, and the injector LEDs on the JimStimX should blink--assuming you loaded the firmware, the base map, and configured it for the FC RX7.

 

Good to hear you got it working. Just remember you may still have to tweak the Vr pots when you actually get it on the car. Sometimes they aren't as clean/powerful as the jimstim.

Stoked to see you got it working though!!!

 

One thing I need to add. Above 3600RPM on the StimJim, I lose the RPM signal. I don't know yet if it's a limitation on the StimJim or if the MS3 is not completely configured. The rev limiter is set to 8500 fuel cut only.

 

One more thing I completely forgot about in the settings on the JimStim: Wheel setup.

Curently, you want all DIP switches set to OFF except 5, which is set to ON. This emulates 24/2 Nippondenso.

 

im not sure why you need the jimstimx for this. Couldn't you just wire into the ms3x connector?

 

Because I started with the MS3/MS3x kit and wanted to bench test. I couldn't wire it into the car because I didn't have all the parts yet; I only started teardown last weekend.

Testing the MS3 using the JimStim saves me a lot of time and frustration determining whether a potential problem is with something in the car, or the ECU.

 

Understood. But I am wondering if I need to buy a jimstimx. I have a Jimstim but it just seems like I could wire the 2nd trigger signal of the Jimstim to the cam pin on the ms3x card and achieve the same results. With that said I did try that and didn't see any rpm signal on my tuning software...

 

I must have some setting wrong because my software tach is jumping a round like a jack russel terrier on crack.

 

ok i think i got to where you are at. I can get up to 3800 rpms and the it craps out to 0.

 

Glad to know that it's not specific to the MS3 and more likely a limitation to the JimStim. I hope once I install the ECU, start up and start tuning that I don't have any issues with the CAS signal. I actually have run a new shielded 4-conductor cable, grounded and all.

 

I actually need to amend my answer, because you didn't mean why bother buying a diagnostic tool, you meant do you really need the JimStimX expansion card if all you're doing is checking the CAS signal?

Well, when I decided to go the MS3 route, I started by buying the kit forms of the MegaSquirt, the JimStim and JimStimX--which saved me some money and gave me a chance to hone my soldering skills and learn a bit about how the ECU worked. I didn't bother buying the MS3 and MS3x harness pigtails until last month.

Could you just tie into the DB37 plug from the JimStim? Yes, you can. But, the JimStimX also has LEDs for indicating the operation of the injector and ignition outputs, as well as the inputs and outputs for things like AC and SD card logging (which I fully intend to use).

If you had a bunch of LEDs, switches and current limiting resistors, there's no reason you can't go that route over the JimStimX. I just find the solution of a simple card you can plug in requiring only three jumper wires to be far more elegant and reliable.

 

Yeah I built my jimstim a while ago and built it before anything else to practice soldering too.

Im not too sure about not seeing more rpms though. Seems a little fishy to me. I'll let you know what I find.